I like riveted in most cases. Only reason I would ever get a welded boat is for serious stump jumping, and the only reason I would go welded is because riveted jons are usually much thinner than welded ones. Need that thicker bottom to go log sliding and jump beaver dams. Other than that, I stick with riveted boats because they are easy to fix.
you need to come up to wa st or oregon,,theres a few of these boats around,,been seeing a few lund boats every once in a while,,its all about welded aluminum boats out here,,hewescraft searunners,,no river,alumaweld ,duckworth etc ,,i would never own a riveted boat , i currently own a new 2023 hewescraft seerunner,,if im out in the ocean hitting some rough chop im not gonna worry the boats going fold etc
Apples to oranges...boats made of thicker aluminium plate like you are listing are better welded, lighter gauge boats are stronger riveted@@andyyarrington6401
@@BADBRAD1959 Both you and Andrew are correct. It's all about the surroundings you'll be in. I, myself would never take a 19 foot (Riveted OR Welded) aluminum to an ocean start with. But I would also like a Hewescraft. They are built nicely, for what I need.
Aloha. I'm 64, and raised here in Hawai'i. Back around 1982 my father ordered a 13'9" riveted aluminum hull Sears Gamefisher skiff thru a local Sears Robuck store. I used to take this boat 20 miles offshore into the deep blue Pacific in pursuit of pelagics - tuna, mahimahi, wahoo, just to name a few. Sometimes the seas would pick up, with whitecaps all around, and the hull going airborne half the time while jumping the swells. It really took a pounding way beyond what it was ever designed for, and it took this abuse all in stride. I owned that boat for 20 years after inheriting it from my dad, and the rivets never leaked, or got loose, but stayed watertight. I made sure to wash the hull down with freshwater after each use. She served me well with no complaint. 😁🤙
I've been making mig welded aluminium boats in Wales UK for 25yrs + we use 5083 marine grade aluminium, minimum thickness for hull construction is 5mm anything thinner with current regs you wont get coded as a fishing vessel or for passengers. ( a lot of our boats are sold for domestic use) A couple of things that are bad for aluminium is brass, copper, (never use) and stainless steel fine on bare aluminium but if you paint and don't use plastic inserts as a barrier for your fixings a reaction happens with sea water, the paint blisters, this is one of the reasons we tell customers don't paint wrap instead if you have to, but your better off leaving it bare, and wash the boat of with clean water each time you use it if possible. Rubber mats we found when placed in a locker or on a deck you can get some corrosion as rubber contains sulphur, we found it bad in lockers that get very damp, you get a funny salt deposit, left unchecked does cause corrosion. That's why we install PVC rubbing strip and PVC matting when required. the other advantage of aluminium boats over grp is at the end of the boats life what do you do with grp???? an aluminium boat you cash it in at the local scrapie, then sometime later go buy a 6 pack of beer which used to be your boat and enjoy.
I do aircraft structural repair for a living , I fix aluminum boat hulls on the side …the majority are riveted but, the welded Princecraft and Crestliners I fix are brutal for cracked ribs and low penetration on seams
Are you seeing it on certain hull types because my Crestliner 1650 Fish Hawk has been solid with no cracking whatsoever model year was 2018? Thanks for your feedback.
There are almost Zero heavy commercial boats or Coast Guard inspected passenger boats that are riveted. Riveting is great for light weight fun boats, but all the heavy aluminum work boats are welded. Each serves it's own purpose accordingly and should not be compared or confused.
Exactly right. The recreational sheet metal boats are about as thin as can be welded and retain good weld margin strength. Riverted or welded, neary all of those boats have a .060" topside (above waterline) thickness with a .100" floor pan thickness.
I have a 1964 Strarcraft Chieftain lapstrake riveted boat that has only needed 2 rivets replaced over the years. This boat ran in Puget Sound in big water and is now running on larger lakes so it has seen the test of time. I also have a 2006 welded boat that has had to have 2 repairs already. Your point about a riveted hull distributing the stress is spot on.
Here in Australia, aluminium boats are hugely popular. Only dingys tend to be riveted, larger boats are all welded. I hear what he’s saying about cracks potentially cracking but I’ve been using Ali boats for years, mostly offshore and I’ve never seen a crack occur in a hull.
Boat put together with rivets that sales guy will say rivets are best. Welded boat dealer will say welded is best. Have heard of welded boats cracking but have also seen boats leaking at rivets and cracks starting under the rivet area
I have as well. A lot depends on how you treat the boat. I was tough on my welded jon - drove it hard and fast in open chop. Hit some really big boat wakes. The cracking was at the front corner where the forward seat was welded to the side. Just a hairliner about 1/2" long on both sides.
I bought a brand new Valco 13 Ft aluminum boat. Riveted. After about 8 months of bay and close in off shore fishing, t was leaking through a LOT of rivets. Sent it to Valco under warrantee and they WELDED ALL the RIVETS>
Cuz its harder to manufacture, Price doesnt always equal the best quality, For example in gun industry Nitrite barrel is simpler than chrome alloy to manufacture, hence the latter is more expensive, yet Nitrite barrel are more durable, less exposed to corrosion and more heat resistant
because the aluminum grade was cheaper, you need to know the grade of the aluminum before making a decision! Semi trailers are made from multiple aluminum grades. Its a simple equation in manufacturing! Take cost of materials and multiply it by 2.5 and there's your general labor for a boat (multiply by 4 if wood). Cheap low grade weldable aluminum can be riveted with a little gain in strength. They fail to express the difference in aluminum grades here!
Thin walled aluminum like alumacraft, lund and crestliner use should be riveted. Welding distorts the shape around the bow. Welding should be reserved for 0.25” and thicker material. 8:008:00
I was in navy but got out and got certified in aluminum tog and mig and D1.1 steel 1992 worked thunderjet riverboat then Renaissance boats , Duckworth , northwest and weldcraft aluminum jet boats they are all great boats but I bought a riveted boat and gave it Hell on the snake river .im in virginia with it right now.
Let’s get someone who knows metallurgy involved, specifically the aluminum alloys. Aircraft grade aluminum is not weldable safely, that’s why it’s riveted.
@@gregketcher2786no matter the alloy, even 5086, you cant put aluminium over high temperature, not because its fusion point is over 650 °C you can weld it over 330 otherwise youll weaken the piece
Down here in NZ there are no rivets in boats being built nowadays . All new boats are fully welded. There are still some older riveted boats around bit they are not popular due to leaks, cracks and fatigue.
I haven't had a ton of aluminum boat experience but we rented a fishing boat on lake Mojave 30 years ago and we got caught out in the ubiquitous afternoon wind storm. The resulting waves forced us to run for the shelter of the cliffs. That run to the cliffs took us into the waves for 20 minutes and when we pulled into the cove several seat rivets had popped. I know that a welded structure in race cars and mountain bikes are very rigid but I've broken several mountain bike frames.
Amen brother I don't have to bail water any more with my welded hull and it takes a lot more of a beating than my riveted one did. In big water I used to watch the water squirt between the rivets on the bottom in the old junk.
In bigger water fiberglass is the way to go. You'll stay a lot warmer and the extra weight will help with ride quality. I've been on many different boats in the pnw from lakes, rivers, Puget sound and Pacific Ocean. The worst boat was the 24' Alumaweld. It beat the hell out of everyone with small wind and tidal waves and it was noticably colder outside temp was 65°. The 24' Trophy and Grady White smashed through the same amount of waves and noticeably warmer and the outside temp was 10° cooler. Ocean temperature was the same. Running rivers I'll take an aluminum all day with a pump.
Rivets allow more flexing in the hull as well as more expansion & contraction. Welding is more rigid but the heating process can fatigue the surrounding metal, later on due to metal fatigue, imperfections in the weld/metal prep, wear & tear, a crack will form.
Man nice I recently got a older Gregor 12ft all welded aluminum boat with a rebuilt trailer both in excellent condition, and got a new Mercury 15hp EFI motor, boat is rated for a 20hp, can't wait to hit the water !
I know absolutely nothing about welding or rivets but I had a riveted boat for decades and I never had any issues. It was an old Mirro Craft. It was great little boat and I ask it to do things I know it was never meant to do.
Thin aluminum is very tricky to weld but can be reliably riveted. Bigger offshore workboats that have to be made of thicker aluminum sheet and plate are always welded, never riveted. Airplanes have to be made in lightest way possible. This puts the structure in a more risky cyclic fatigue regime. Also, various materials and thicknesses have to be connected together in the structure. This all favors riveting ... but demands periodic inspection at designated intervals calculated from fatigue life and corrosion rate calculations.
In aircraft the main factor is the heat treatable alloys that must be used to achieve the necessary strength to weight. These alloys cannot generally be welded, so rivets must be used. If they could make a weldable alloy that would maintain the same strength as current aircraft alloys even after welding, then all aluminum aircraft would be welded.
I think u hit the point good. Difference between thick aluminum plate and the thinner hull boats being produced. Thin aluminum plate likes rivets over welds
In most cases, aircraft are not submerged in water. Completely different application. It was kind of inexplicable why he would compare aircraft and boats.
@@jbj27406 And yet, most aircraft floats for seaplanes are made of riveted structure, for the same reasons as the aircraft they are mounted to (allows use of high strength, non-weldable alloys).
@@netpackrat Agreed. That exception occurred to me also. However, the average aluminum fishing boat is not built to float plane or seaplane standards for the reasons you suggested. The standards of construction and materials is far more advanced and critical in aircraft. And weldability is probably counter to skin/structure strength.
Today both welded and riveted hulls are excellent. I own a Crestliner (welded) and a Lund (riveted) which see a lot of big water on Lake Erie and Lake Ontario. I would give the nod to the welded hulls for the following reasons. Welded hulls are more efficient than riveted do to there being no rivet heads to interrupt water flow over the hull. Also it is easier to repair a welded hull because you can identify where the leak is and repair it without the need to remove decking as you need to do with a riveted hull. Saying that, both boats l own have no leaks but both boats have had to have their transoms repaired do to the transoms wooden construction. The gentleman's information about trucks and planes being riveted is not entirely accurate. The frames of most transport trucks are held together by Huck bolts not rivets in areas that see the highest stress. Most air planes do use some rivets but in high stress areas Huck bolts are used. I make this statement from experience as an air frame mechanic assembling and repairing DC9's wings at McDonnel Douglas. Hull warranty the manufacture offers gives a good indication of how confident they are in their product. Crestliner, life time on the welded hull. Lund, life time on only the double riveted seams. Alumacraft 20 years on the riveted hull. Also both welded and riveted are subject to material and manufacturing defects.
"Also it is easier to repair a welded hull because you can identify where the leak is and repair it without the need to remove decking " WHAT??? Who ever conned YOU into believing that? Have you ever welded aluminum? That surface needs to be heated tremendously prior to any weld, Do YOU know what's on the other side of that hull? They ARE and WILL gut that portion of the boat out to get to the other side, guaranteed. Please, please, please, never try to fix anyone's boat.
Yes l have welded my aluminum hulled boat, and yes l did know what was on the other side. But l did have to remove one floor panel but did not required to remove the floor to find the leak. Now with my aluminum boat the only way l could find the leaking rivets was to take out all of the flooring, dry the floor and then float the hull to mark which rivets needed replacing. Next l had to drill out the rivets and then install the new rivets, which takes two people. One to buck and the other to rivet. Please please never try to tell anyone anything. @@BumpNrun69
In the interview and following conversation presented here, I can not help but say that the elephant in the room has been ignored. I would never provide any criticism for the structural component of an aluminum boat as they are well proven. Nor would I argue against replacing a rivet or rivets in an aluminum boat. However, out here in the field as a repairer we see a very large number of leaking aluminum boats, some with loose rivets and some not. The issue absolutely is not the rivets it is the bonding agent used on the seam to increase the strength and seal the seam. It becomes delaminated, and then the boat leaks. You can tighten or replace rivets, but you can't replace the bonding agent properly without totally disassembling the seam that is leaking, which would be cost prohibition . You can seal the seam on its edge, but with the bonding agent nullified sealing that edge doesn't seem to last very long.
The other elephant in the room is how rivets "distribute" the energy of that 1 foot chop. He won't say it, but they ever so slightly move. You can see where that's going...
Okay, both are good ways to build sheet metal boats of thin guage. However, I have experienced one thing that happened to a welded boat, which I have not seen on riveted. I will not name the brand because they are excellent boats. That said, Ihad a 16ft jon wit a very shallow V bottom. Driven by a 35 hp tiller control motor, it was fast, I can tell you. Out on Puget Sound, it can get choppy - not the best environment for a jon with 20 inches of freeboard. And, certainly not teh best environment for a flat running lake hull. As I used it over a couple of seasons, I noticed that the margins at the welds in certain spots were cracking. Not weld itself, but the sheet metal just next to the bead edge. Iassume it was material hardening when it was welded. We're talking .060" sheet - easy to get it brittle. I went on to use the boat, but cut back my bay running and took it to lakes instead. I was probably abusing it, but I'm just sayin'. Today I have a 2000 Northwood (Smokercraft Voyager), bought used, and have never had an issue in a chop except for soe pounding because it's so light. No rips or cracks at stress points. SO, I think matelfatigue or process hardening may be a thing with welding very thin aluminum.
a Jon in heavy seas is a bad idea no dead rise to handle the heavy seas glad you got in OK Jon boats are good for small lakes rivers and some smaller bays out on a big body of water bad idea... I bet that was a stressful ride especially with a tiller weight distribution is critical to lessen bow slap. 16 foot Aluminum deep V with a 20-25 degree dead rise at the bow would have been a way different ride.
@@kenneth9874 T-6061, like all quality aluminum boats. It's hardedned and much stiffer than comon sheet alloy. Used in aircraft bodies. Think: Grumman canoes. The cracking was my fault, I'm sure. A welded jon will last as long as any good alloy sheet boat if used as desdigned - not wave hopping at 25+mph. I'm talking 2ft waves and large boat wakes. For the record, the brand was Crestliner, a very good manufacturer. The cracking never got any worse, and the boat was completely satifacory. I would recommend it to anyone. My Northwood 14 is a completely different design, being a re-badged Smokercraft Voyager, made by a Smokercraft subsidiary. It is a wave cutting design for large open lakes and sheltered bays, and handles chop very well because it has more V at the entry - graduating to a semi rounded transom for planing. Both are excellent boats for their intended purpose.
@@kenneth9874 True, but T6061 has always been the Go-To alloy for aluminum boats in this class and works amazingly well, given the overwhelming number of them that are older than their owners. Aircraft made of it have th same fatigue and cracking issues. If you look very close at WW2 Grumman fighters, you'll see all kinds of quick fix patches riveted on over bullet holes and stress cracks. Russian fighters were much more crudely built, and used lots of soft aluminum, which actually ripped. More patches.
Ive owned a few aluminium boats or tinnys as we call them in New Zealand. My riveted ones had to be re riveted every few years. But my last two have been welded much superior. I currently have a 4.30 side console 5mm hull 4mm sides its great. I dont go out in rough conditions
I have a 16' Quachita purchased in about 1970. Had a Corvair airboat setup on it for several years and then switched to 40hp outboard. Most of the boat is riveted to the hull stiffeners and seats. The bow is welded as is the transom. The only crack developed in the bottom where a bottom groove was formed by pressing I think. Some of the rivets started leaking so I got my son to hold a hammer on the outside while I hammered them flatter from the inside. The only welds that broke were the gussets to the transom on the gunwales. Boat has been well used and still has a lot of life left.
I have a 20 year old Starcraft aluminum v hull that I use primarily in salt water. It doesn't leak a drop and has been perfect for me. It's just a 14'3" but takes two guys fishing in bays and in decent chop with a 25 hp motor and moves right along. I love it after scaling down in steps from longer boats. I'm old now so it's easier to handle alone. 😀
Post weld heat treatment of aluminum is required for optimum strength, planes would be lighter being welded if there was a practical way to build wings, welded and heat treatment without warping etc.
Couldn’t agree more. I’ve owned a 20’ Lund Alaskan since 98 with high hp tillers and pounded the hull hard over the years and to this day it doesn’t leak a drop. Aluminum hulls have to flex and welded joints are too rigid and will eventually crack. Ask my different buddies over the years who’ve bought new welded hulls and they had nothing but headaches and they vowed never to own welded again. YMMV
Ive got a 25 yr old riveted 14' riveted boat, always used hard and still dont leak a darn drop. Naden. Canadian made. Im the 3rd generation owner of it and will pass it down when the time comes.
The second time I've visited this same video. The debate goes on, and probably always will. Coming from Minnesota the debate is strong there where you have Alumacraft and Lund riveted boats going up against Crestliner welded hullls all made (or were?) in that state for the same choppy waters and granite bottomed lakes. Some of the things not being mentioned, and I'm sure there are more when you bring in welded boats of the Pacific NW and southern jon & bass boats and the types of waters they run in, are the other things like improved adhesives between riveted panels and the tongue & groove extrusions some welded hulls use. Suffice to say, buying from a quality manufacturer with good dealer support and it probably boils down to personal preference.
To compare a welded aluminium boat to an aircraft’s riveted construction is an apples to oranges comparison. The alloy skin of an aircraft is thin to keep weight down and as such would be difficult to weld for starters . Rivet holes are notorious for having cracks migrate from them , but easy to repair with doublers etc . Plus easier to replace damaged parts or gain access ie to inspect inside wings etc . By comparison most welded alloy boats are 4-5 mm thick and the quality of welds today is impressive . As an example , our 7.4 m alloy boat was built (welded construction ) in 1992 . No welds have ever failed and it’s had a pretty hard life , off the West Coast of NZ . We did have some pitting in the alloy of the hull , but they just cut out that section and welded in a new section and she’s good to go again .
I about sunk in a late nineties 19’ riveted hull boat I purchased used. I didn’t see any signs of of loose rivets before taking it out. Luckily the auto bilge came on and started draining and I hit it back to the dock. I’ll never own another in that size.
With anything less than 3/16” i can agree I have experience in work skiffs with 3/16” sides and 1/4” bottoms And i do think there is an application for both methods Bottom bracing and framework layout is critical in both applications Weight and foam for structural integrity is also part of the equation hull materials, joinery,design, application, maintenance, hp requirements, cost is very end user specific Thanks for posting!
This! A sheet metal welded boat is very different from a plate welded boat. Crestliner tracker lowe are sheet metal boats when welded changes the temper of material at weld location and if any cracks they will start there and spread. Rather have rivets in sheet metal and welded plate. I have both neither leak and each has its applications.
@@omieyouknowme "when welded changes the temper of material at weld location and if any cracks they will start there and spread"... Finally, someone who is educated enough to understands the chemistry of a weld. Many people here are so clueless to this fact.
@omieyouknowme marine plywood, 'glass and epoxy composite hulls are excellent. They're durable, easy to repair, quiet and warm. Plus, wood floats. Kind of makes sense to make boats out of it, but it's not as profitable to large companies as cranking out aluminum hulls.
dude thought he was sly saying there was more labor with 2 people bucking rivets. haha. its faster and non-skilled. its cheaper. thinner aluminum is MUCH MUCH cheaper and can be cut, bent in a brake, and riveted. entry level workers with no experience can be trained to rivet in 15 min. application is everything though. if you don't need welded, don't buy welded.
My father bought a Duracraft 1648 DD back in 1996. He put a Go Devil long tail on that boat so we always run it in shallow water. We’ve hit more stumps than I can count and that boat has held up phenomenally well. We have never had a problem with it. I definitely prefer welded aluminum boats over riveted aluminum boats. I don’t think a riveted boat could survive the abuse id put it through.
Yep, rivets can create elongation within their the holes. Welded joints throughout time create "weakest link" points scenarios; next to the weld itself. I'll take the "rivet" design any day of the week.
@@NoneOfYourBeesWax1 Also you tell us the difference of the Steel and Size of the Steel being used on them application. Big (Huge) difference in applications than a sheet of aluminum hull less than 1/8".
The reason aircraft use rivets is because they have no need to be water tight and if a panel is damaged, they can remove the rivets and rivet a new panel in place much easier than welding. If you are welding, you're essentially making two pieces of aluminum into one piece. It's not as easy to repair, but it is stronger and more water tight.
My aircraft floats are Riveted. Sealant is placed between the joint before riveting. Pressurized aircraft are also sealed in the same way. That sealant can become dis-bonded and our floats leak a little during movement. Our aircraft are riveted because the Higher Strength to Weight Al Alloys cannot be welded. Friction stir welding of our alloys has been tried as a manufacturing process but not widely adapted or field repairable.
Most aircraft are air tight.... they use rivets because the UTS is calculable and reliable. Also, because the heat treatment is lost in the HAZ. pretty tricky to heat treat a whole airplane.
Aircraft grades like 2000/7000 series can’t be welded because the heat takes the temper out of the material. Both grades aren’t great for welding. Most boat manufacturers use 5000 series of various types, these are not heat treated grades
I am on my second riveted aluminum boat. I gave up on the first one after it leaked 2” of water into it overnight. The second has not leaked in 10 years. It is an Alumacraft.
I owned a welded Crestliner and a 12” seam split open in the hull. No rough stuff. I checked with the dealer and they called Crestliner and the repair was approved. A local weld shop did the repair and sent the bill to the dealer. We do have a riveted boat as well and no issues with it.
Alot of both , really depends on the quality of the work done by the riviter or welder , weather its monday or friday , quality of mayerial is key to any things man made , but if your builder isnt on top of his or her game then your product suffers .
The alloys common in aviation are also more susceptible to corrosion. Re-skinning and corrosion repair is common just from condensation or washing with car wash soaps; gotta use corrosion inhibiting soap to avoid problems.
Aircraft grades of 2000 series for the fuselage are clad top and bottom during the rolling process. The clad is usually a 1000 series to provide corrosion resistance.
That Aluma Craft looks very light weight compared to the 5mm plate alloy, full stringer sub floor frame construction and fully welded-in alloy floor on my Australian built boat. I've never seen a weld on my type of craft ever crack.
I bought a new Crestliner aluminum, all welded, boat in 2001. I ran it through heavy waves without having any problems. I think Alumacraft to too cheap to upgrade their manufacturing to welded boats. They are trying to convince potential customers that the obsolete riveting is superior to an all welded aluminum boat. I'm 66 years old and had many boats (aluminum and fiberglass)and the Crestliner welded aluminum boat is the best boat I ever had. ***I say BS to this video.*** Buy the way I don't work for Crestliner, I never had and I will not make any money or benefit from my comment. I giving my honest opinion.
Welded is much less likely to crack then around a rivet. Rivet is actually cheaper to produce than welding due to the time required. But welded is stronger and more watertight. That is why welding is used where strength is required. Trucks use oversize box and riveting for cost and speed of production as they do not need to be watertight.
@@BumpNrun69 And putting hole in it and then filling it with a rivet is even weaker. I did NDT for several decades and know which I would choose every time.
Interesting theory… But as a kiwi aluminium boats are very very popular here, and in a country of 5 million there must be 30-40 companies making them in all shapes and sizes for Southern Ocean conditions from 3 meter “tinnies” to fish palaces with all the bells and whistles for diehard fisherman, and I’ve never heard of any mainstream manufacturers having issues with cracking welds. Makes a great sales pitch, but a well designed, well built welded hull will give you no problems in any conditions. Go to a boat show here and probably 60-70% of the boats on show, will be aluminium. They’re the fishing weapon of choice. None are riveted.
I was teaching shop in Alaska , a guy had a welded aluminum boat . He found out the hard way aluminum welds are weaker than the parent metal. I patched it till he could get back to where he bought it .
We had 1997 17 ft aluma craft with a 115 johnson. It leaked from the start! Factory took it back. I bought a 1998 crestliner 17 . With a evinrude 115, its top end is 4 mph faster. No leaks no squeeks and used on big water. Lake vermilion!!!
To me, the pinnacle of aluminum boats are the Coast Guard 45-foot response boat-medium. By pinnacle , I mean if I could have any aluminum boat, I desired, this is the one I would pick. Obviously I would want more luxury than the .mil version, but the self righting ability, hull design, dual 6 cylinder diesel jet pump powered drive. Joy stick controlled. It is designed to operate in 8 ft seas and survive 12 ft seas and 50 knot winds. Is it riveted or welded? AND we all know the government doesn't always pick the best of the best, but instead often pick the cheapest unless there is a reason for the more expensive option. As far as I know, the RBM45 is welded since you can find the CG requirements for repairing any welds online. I assume there is a reason for picking the more expensive option. AND this has no real context except it is a fact and it was a famous ship that sank. The Titantic was riveted. lol
The problem in comparing the two modes of construction is that of build quality and design. Crappy boats have been built using either technique which will then firmly put people in one camp, or another, depending on their personal negative experience. Done properly there is likely little real world difference between the two methods, although personally on smaller boats using thin aluminum, I prefer rivets, just because welding thin materials produces a real chance of compromising the base material and it cracking.
@@TheErsatzMode you're assuming the whole weld is perfect, very few industries hold their welders and welds to that standard. They do have allowance on impurities per 12 linear inches of weld. To say the welder and or the robot will lay a perfect weld from start to finish every time is living in fantasy land. So as I said unless you personally welded and tested the hull yourself. You can't guarantee the weld is water tight. Aluminum welds are prone to crack especially when MiG welded if not done perfectly. You can easily find stories of boats with broken welds with new ones daily.
Seems to me if I have to replace a rivet, Im out a day of fishing, it's going to cost money, and cracked weld is likely to be repaired from inside not out. so not sure why the rivet has any advantage on that.
A closed end blind rivet and some under waterline marine sealant allows you to replace the rivet from the outside. Aluminum has to be prepped properly and cleaned spotless to be welded properly. And it puts a lot of heat in the area. Both sides of the weld should be prepped.
Thinner aluminum sheet is difficult to weld effectively. Manufacturers use thinner material to save money therefore really have no choice but to rivet. They don’t rivet because it is superior, just superior for the material thicknesses they use. Most river boats that are required to run over and survive rocks, sand, and logs, use thicker formed and welded aluminum sheet/plate. The thicker material allows welding without overheating and burn through like you would see on the thinner material used on riveted boats. The flatter the bottom the more it will flex too. That is why you need the thicker material as well. I’ve seen many Jon boats that are riveted start to leak because over time they start to fatigue from flexing so much. I’m talking about the thin walled RIVETED ones. This isn’t because they are riveted, it’s because cheap thin boats that don’t hold up must be riveted because welding isn’t an option on boats that thin. There’s also the fact that rivets on a boat don’t take 2 years of trade school and years of practice to master. I would say on a production line a hard working unskilled person could learn to rivet fairly quickly where as putting out a “stack of dimes” is very difficult therefore a competent welder would cost the manufacturer much more.
the smaller Starcraft riveted boats held up fine for decades but would leak unless the rivets were re-bucked. the larger ones, 20 ft and over were prone to cracking along the bottom between rivets. we have a 1967 Starcraft 14 foot and it's still doing great.
I never weld cold Aluminium. I insist it must be pre-heated before being MIG or better still, TIG welded. Yes this takes time and costs more. That is why some do not bother pre-heating.
My polar kraft bass boat is riveted and my concern is in future having to possibly remove flooring with new carpet to replace rivets. And welded boats that are painted. Will have to be touched up.
I have owned 15 fishing boats. A long time ago, I.bought an aluminum boat that had been used strickly in salt water fishing the bays in Texas. Every rivet on the boat leaked. I.coated the bottom with polyester fiberglas cloth and resin. Never leaked .a drop after that. I now own a 16' 8" Tracker. I.bought it because it is light, and was inexpensive. I fish small 1000 acre lakes that rarely get any chop on them. If it is windy, I don't go. I hate fishing in the wind. I bought aluminum because they are lighter, require less maintenance, and since I usually fish alone, are much easier for me to manage. When gauging toughness, I look at what they use in Alaska. Their boats are all welded aluminum. All.of them.
@CaptPeterson Do not forget Polarcraft. My Dad had one for well over 30 years until he passed. The point is you could run that boat up onto the rocks and pound the dents out of the boat, and she was good to go.
There is absolutely no comparison to the stress loads between a fighter jet and a boat. For one, a jet has riveted panels specifically so they can be removed to access interior repairs. Jets don't bang their way through the air the way a hull bangs across rough water. Welded hulls are more rigid and therefore stronger. Riveted hulls flex. Metal that flexes succumbs to metal fatigue sooner. That said, a riveted boat is fine for small waters not subject to significant chop and waves.
I’ve had several welded aluminum boats (and pontoons) and never had a leak. When I was young, we had several riveted John boats and they all eventually leaked
I had a 1980 Monark 1448, riveted hull with Welds on each side of the bow... I don't remember how many times the WELDS Failed and had to have the welds repaired. Riveted portions never failed!
@@Comm0ut I had the same problem with an old Fisher Marine. Boat leaked so bad from rough water that I filled it with water on the trailer to find the leak and it looked like a boat shaped shower head.
I had a Crescent liner split a weld, suppose to be a life time warranty. Took it to the dealer, they talked to the factory, approved it and the dealer paid the weld shop. It was 5-6 old at the time.
@brittseverence7221 i dont think thats the reason it sunk, it would've sunk even if it was welded with such impact only a thicker hull would've survive the iceberg
Ironically, the likely reason the Titanic sank so easy was due to heat fatigue of the metal from the coal power plants. The same thing can happen if a welded boat is not welded properly. Although, probably not often
Comparing plane and boats is further than apples and oranges... types of stress, vibrations, etc are completely different. Fiberglass boat builder with 40 years experience and also have owned a few smaller aluminum "skiffs" - smaller boats under 18ft for lake use in short interval wind chop = 100% riveted will outperform in most cases ... when you get into larger scale BC/Alaska ocean boats from 20ft-40ft - you will see 100% welded 100% of the time
I've had two riveted boats and both started leaking on the place where the studs from the trailer had contact. It's not so much the bumping on waves but it's the transport on a trailer that causes leaks. I own now a welded made in Finland Buster boat for many years and the quality and performance is not comparable with Aluma Craft etc. I should have bought a Buster from the beginning than i saved a lot of money and trouble.
Riveted boats leak from heavy waves over time. Welded boats don’t but are more expensive initially. Welds can crack however if they are not done properly. Not all welded hulls are equal
This is the only comment I found addressing LEAKS. 99.9% of boats are plenty strong enough in the conditions they were build for.... Over time, rivets leak. I like a dry boat.
Airplanes are Riveted because of dissimilar metals. The F14 was specially treated with 6000-grade aluminum with a titanium structure. We Rivet because you can't weld them. Some of the new stuff is heading to composite epoxy laminate.
Try and find a welded fuselage on any aircraft, not gonna happen . Standard practices are approved by the FAA …a titanium Hilite is stronger than any weld
My point was you can't weld aluminum to titanium or other dissimilar metals. Also, some of the aluminum used in airliners are in either the 2000 or 7000 series of alloys and they are considered to be non-weldable. There are plenty of world war II, p2s that have fully welded aluminum fuselage. I've seen one fully restored. All welded and polished to a mirror finish, it's really a sight to see.
The main alloys used in aircraft construction are heat treated and usually not considered weldable. So bringing aircraft into the discussion is misleading because they have to be riveted. The only places you will normally see welded aluminum in aircraft are for items such as tanks, or non-structural fairings. Since those components are not as highly loaded, lower strength, weldable alloys can be used.
@@colt110987 Being water/air/fuel tight doesn't really have anything to do with welding vs. riveting. Many tanks are riveted, and an integral part of the structure, more so the larger the aircraft gets. On light aircraft, there is less advantage to having the tank built into the structure, and since they only have to support the weight of the fuel they carry (as opposed to being part of a wing's primary structure), then it's just easier to make them out of a lower strength alloy and weld them. Also consider that many aircraft made of riveted structure have to be airtight because they are pressurized.
I had an xpress bay boat. I had the welds fail three times and different places. Never had a riveted hull but I will never buy another xpress boat again
@ was it an x bay? I’ve talked to a couple people here in south Louisiana that that particular one seems to have problems. If spread doesn’t cover it under warranty it’s crazy expensive. They had to take off part of my upper deck to get at it inside and from the bottom
I have a 1988 v16 alumacraft riveted boat I’ve owned it since 1990. It has never leaked. I replaced 2 rivets where the seat brace meets the seat. I don’t honestly think it makes much of a difference.
Rivits disperse the load across an area the diameter of the rivit at each rivit point. A weld spreads the load evenly along the length of the seam. At the point of failure a popped rivit transfers it's load to the next rivit which wasn't designed for that load. The rivits start popping like a submarine movie. This leaves holes where water jets in. We'd have to try to break our welds in shop class and the weld should be stronger than the surrounding metal. A poor weld can erode the surrounding metal and create a thin spot. Heat can harden the metal and make it brittle. Modern robotic welders sure make some pretty welds and rarely over cook it.
on my second welded boat been in rough seas many times landed hard many times no issues tired of rivet guys saying welded boats crack that's BS I think both are good and its a stupid discussion and air planes have big temp and pressure changes that's why its riveted pretty sure a boat will not see the kind of changes a plane will see.
You don’t have to always use two people to buck a rivet. There are many tools out there like squeezers and alligators with various reaches.. Spend the money on the right tools and you’ll save money in the long run
I have a 2001 sprint marine ocean pro and ive beat that boat up many years still running strong welded boat on the colville river i live in Nuiqsut Alaska
I will stick with a welded boat despite what this 2nd generation riveted boat builder says. Every riveted boat over time ends up leaking eventually. Good luck pinpointing the leaking rivets.
The British can tell you about rivets because they stopped using them on their tanks in WW2 because after an impact they would pop and kill the crews in the tank.
It’s all based on the thickness of the material thin aluminum needs to be riveted, but please understand that mega yachts, which are hundreds of feet long use sticker aluminum and they are welded and weld because the material is thick enough
The first aluminum boat I owned was a leaky pos after a few years. "riveted hull". I sold the piece of junk and bought a welded hull boat. The person up front never had to "Bail Water" all day any more. If you plan on owning the boat for a long time DO NOT buy a riveted hull. You'll be sorry.
![Noob To Max With DRAGON REWORK In Blox Fruits [FULL MOVIE]](http://i.ytimg.com/vi/LnBMOinoOvA/mqdefault.jpg)
I like riveted in most cases. Only reason I would ever get a welded boat is for serious stump jumping, and the only reason I would go welded is because riveted jons are usually much thinner than welded ones. Need that thicker bottom to go log sliding and jump beaver dams. Other than that, I stick with riveted boats because they are easy to fix.
Wisdom bro. We need to hit up a boat show one of these days!
you need to come up to wa st or oregon,,theres a few of these boats around,,been seeing a few lund boats every once in a while,,its all about welded aluminum boats out here,,hewescraft searunners,,no river,alumaweld ,duckworth etc ,,i would never own a riveted boat , i currently own a new 2023 hewescraft seerunner,,if im out in the ocean hitting some rough chop im not gonna worry the boats going fold etc
Apples to oranges...boats made of thicker aluminium plate like you are listing are better welded, lighter gauge boats are stronger riveted@@andyyarrington6401
@@BADBRAD1959 Both you and Andrew are correct. It's all about the surroundings you'll be in. I, myself would never take a 19 foot (Riveted OR Welded) aluminum to an ocean start with. But I would also like a Hewescraft. They are built nicely, for what I need.
62 yrs old a welder since 16 and a CWI for the last 30....rivets are not stronger than welds...they are cheaper.
Be honest!
Aloha. I'm 64, and raised here in Hawai'i. Back around 1982 my father ordered a 13'9" riveted aluminum hull Sears Gamefisher skiff thru a local Sears Robuck store. I used to take this boat 20 miles offshore into the deep blue Pacific in pursuit of pelagics - tuna, mahimahi, wahoo, just to name a few. Sometimes the seas would pick up, with whitecaps all around, and the hull going airborne half the time while jumping the swells. It really took a pounding way beyond what it was ever designed for, and it took this abuse all in stride. I owned that boat for 20 years after inheriting it from my dad, and the rivets never leaked, or got loose, but stayed watertight. I made sure to wash the hull down with freshwater after each use. She served me well with no complaint. 😁🤙
4:52
im sure a boat captain with lots offshore experience is big part of that equation.
I've been making mig welded aluminium boats in Wales UK for 25yrs + we use 5083 marine grade aluminium, minimum thickness for hull construction is 5mm anything thinner with current regs you wont get coded as a fishing vessel or for passengers. ( a lot of our boats are sold for domestic use) A couple of things that are bad for aluminium is brass, copper, (never use) and stainless steel fine on bare aluminium but if you paint and don't use plastic inserts as a barrier for your fixings a reaction happens with sea water, the paint blisters, this is one of the reasons we tell customers don't paint wrap instead if you have to, but your better off leaving it bare, and wash the boat of with clean water each time you use it if possible. Rubber mats we found when placed in a locker or on a deck you can get some corrosion as rubber contains sulphur, we found it bad in lockers that get very damp, you get a funny salt deposit, left unchecked does cause corrosion. That's why we install PVC rubbing strip and PVC matting when required. the other advantage of aluminium boats over grp is at the end of the boats life what do you do with grp???? an aluminium boat you cash it in at the local scrapie, then sometime later go buy a 6 pack of beer which used to be your boat and enjoy.
By the time you aluminum boat would be due for scrap, you want be able to drink beer... Maybe only tea and pills :) :)
I do aircraft structural repair for a living , I fix aluminum boat hulls on the side …the majority are riveted but, the welded Princecraft and Crestliners I fix are brutal for cracked ribs and low penetration on seams
It's almost as though quality of construction is more important than the method of construction. Crazy.
Are you seeing it on certain hull types because my Crestliner 1650 Fish Hawk has been solid with no cracking whatsoever model year was 2018? Thanks for your feedback.
@@mikerouse6004 2008 Triton VT19, made by Crestliner here. Solid as a rock
princecrafts are mostly riveted
those manufacturers probably used a MIG & spool gun instead of a proper TIG machine.
There are almost Zero heavy commercial boats or Coast Guard inspected passenger boats that are riveted. Riveting is great for light weight fun boats, but all the heavy aluminum work boats are welded. Each serves it's own purpose accordingly and should not be compared or confused.
The thinner the aluminum is the more difficult it is to weld.
Exactly right. The recreational sheet metal boats are about as thin as can be welded and retain good weld margin strength. Riverted or welded, neary all of those boats have a .060" topside (above waterline) thickness with a .100" floor pan thickness.
Ocean going ships were all riveted once apon a time and I've never heard nor seen evidence of one sinking because it was a riveted construction !
Yes even battleships
@@Hitman-ds1ei Oh yeah just like the Titanic!
I have a 1964 Strarcraft Chieftain lapstrake riveted boat that has only needed 2 rivets replaced over the years. This boat ran in Puget Sound in big water and is now running on larger lakes so it has seen the test of time. I also have a 2006 welded boat that has had to have 2 repairs already. Your point about a riveted hull distributing the stress is spot on.
the grade of the aluminum is key to these factors!
Here in Australia, aluminium boats are hugely popular. Only dingys tend to be riveted, larger boats are all welded.
I hear what he’s saying about cracks potentially cracking but I’ve been using Ali boats for years, mostly offshore and I’ve never seen a crack occur in a hull.
Same in New Zealand
Boat put together with rivets that sales guy will say rivets are best. Welded boat dealer will say welded is best. Have heard of welded boats cracking but have also seen boats leaking at rivets and cracks starting under the rivet area
Well.. Maybe we should ask for reviews of all the WELDED aluminum fighter jets. LMAO
@justis4men211 why don't you fly yourself over to an aviation channel to compare apples to oranges
I have as well. A lot depends on how you treat the boat. I was tough on my welded jon - drove it hard and fast in open chop. Hit some really big boat wakes. The cracking was at the front corner where the forward seat was welded to the side. Just a hairliner about 1/2" long on both sides.
I heard fighter jets don’t do well in water, so, there’s that….
I bought a brand new Valco 13 Ft aluminum boat. Riveted. After about 8 months of bay and close in off shore fishing, t was leaking through a LOT of rivets. Sent it to Valco under warrantee and they WELDED ALL the RIVETS>
Then why to they charge more for a welded John boat rather than a riveted boat
Cuz its harder to manufacture,
Price doesnt always equal the best quality,
For example in gun industry Nitrite barrel is simpler than chrome alloy to manufacture, hence the latter is more expensive, yet Nitrite barrel are more durable, less exposed to corrosion and more heat resistant
because the aluminum grade was cheaper, you need to know the grade of the aluminum before making a decision! Semi trailers are made from multiple aluminum grades. Its a simple equation in manufacturing! Take cost of materials and multiply it by 2.5 and there's your general labor for a boat (multiply by 4 if wood). Cheap low grade weldable aluminum can be riveted with a little gain in strength. They fail to express the difference in aluminum grades here!
Thin walled aluminum like alumacraft, lund and crestliner use should be riveted. Welding distorts the shape around the bow. Welding should be reserved for 0.25” and thicker material. 8:00 8:00
I was in navy but got out and got certified in aluminum tog and mig and D1.1 steel 1992 worked thunderjet riverboat then Renaissance boats , Duckworth , northwest and weldcraft aluminum jet boats they are all great boats but I bought a riveted boat and gave it Hell on the snake river .im in virginia with it right now.
Let’s get someone who knows metallurgy involved, specifically the aluminum alloys. Aircraft grade aluminum is not weldable safely, that’s why it’s riveted.
Marine grade 5052
@@gregketcher2786no matter the alloy, even 5086, you cant put aluminium over high temperature, not because its fusion point is over 650 °C you can weld it over 330 otherwise youll weaken the piece
Down here in NZ there are no rivets in boats being built nowadays .
All new boats are fully welded.
There are still some older riveted boats around bit they are not popular due to leaks, cracks and fatigue.
same in australia. riveted = garbage
Yep
Well if they cant use proper joint with rivets to seal them properly that doesnt mean weld is better
I haven't had a ton of aluminum boat experience but we rented a fishing boat on lake Mojave 30 years ago and we got caught out in the ubiquitous afternoon wind storm. The resulting waves forced us to run for the shelter of the cliffs. That run to the cliffs took us into the waves for 20 minutes and when we pulled into the cove several seat rivets had popped.
I know that a welded structure in race cars and mountain bikes are very rigid but I've broken several mountain bike frames.
Only thing of merit that I got from your stories is "your experience from a RENTAL, application"
Jeez.. after owning many riveted boats, I can say I’m very happy to be in a welded boat…
good luck to you, decades down the road.
@@BumpNrun69 My 13 ft welded boat, Duranautic, was purchased in 1974 and has been run hard, and is going strong.
@@BumpNrun69my welded skiff has survived 30 years crawfishing in flooded timber, come try a couple of seasons with your riveted boat...😂😂😂
Amen brother I don't have to bail water any more with my welded hull and it takes a lot more of a beating than my riveted one did. In big water I used to watch the water squirt between the rivets on the bottom in the old junk.
@BumpNrun69 good luck to your leaks
In bigger water fiberglass is the way to go. You'll stay a lot warmer and the extra weight will help with ride quality. I've been on many different boats in the pnw from lakes, rivers, Puget sound and Pacific Ocean. The worst boat was the 24' Alumaweld. It beat the hell out of everyone with small wind and tidal waves and it was noticably colder outside temp was 65°. The 24' Trophy and Grady White smashed through the same amount of waves and noticeably warmer and the outside temp was 10° cooler. Ocean temperature was the same. Running rivers I'll take an aluminum all day with a pump.
Rivets allow more flexing in the hull as well as more expansion & contraction. Welding is more rigid but the heating process can fatigue the surrounding metal, later on due to metal fatigue, imperfections in the weld/metal prep, wear & tear, a crack will form.
Very true, I worked 30 years for a major aluminum company.
Man nice I recently got a older Gregor 12ft all welded aluminum boat with a rebuilt trailer both in excellent condition, and got a new Mercury 15hp EFI motor, boat is rated for a 20hp, can't wait to hit the water !
That's what I have for 43 years so far and no problems at all. Gregor makes the best small aluminum boats by far.
I know absolutely nothing about welding or rivets but I had a riveted boat for decades and I never had any issues. It was an old Mirro Craft. It was great little boat and I ask it to do things I know it was never meant to do.
Thin aluminum is very tricky to weld but can be reliably riveted. Bigger offshore workboats that have to be made of thicker aluminum sheet and plate are always welded, never riveted. Airplanes have to be made in lightest way possible. This puts the structure in a more risky cyclic fatigue regime. Also, various materials and thicknesses have to be connected together in the structure. This all favors riveting ... but demands periodic inspection at designated intervals calculated from fatigue life and corrosion rate calculations.
In aircraft the main factor is the heat treatable alloys that must be used to achieve the necessary strength to weight. These alloys cannot generally be welded, so rivets must be used. If they could make a weldable alloy that would maintain the same strength as current aircraft alloys even after welding, then all aluminum aircraft would be welded.
I think u hit the point good. Difference between thick aluminum plate and the thinner hull boats being produced. Thin aluminum plate likes rivets over welds
In most cases, aircraft are not submerged in water. Completely different application. It was kind of inexplicable why he would compare aircraft and boats.
@@jbj27406 And yet, most aircraft floats for seaplanes are made of riveted structure, for the same reasons as the aircraft they are mounted to (allows use of high strength, non-weldable alloys).
@@netpackrat Agreed. That exception occurred to me also. However, the average aluminum fishing boat is not built to float plane or seaplane standards for the reasons you suggested. The standards of construction and materials is far more advanced and critical in aircraft. And weldability is probably counter to skin/structure strength.
Today both welded and riveted hulls are excellent. I own a Crestliner (welded) and a Lund (riveted) which see a lot of big water on Lake Erie and Lake Ontario. I would give the nod to the welded hulls for the following reasons. Welded hulls are more efficient than riveted do to there being no rivet heads to interrupt water flow over the hull. Also it is easier to repair a welded hull because you can identify where the leak is and repair it without the need to remove decking as you need to do with a riveted hull. Saying that, both boats l own have no leaks but both boats have had to have their transoms repaired do to the transoms wooden construction. The gentleman's information about trucks and planes being riveted is not entirely accurate. The frames of most transport trucks are held together by Huck bolts not rivets in areas that see the highest stress. Most air planes do use some rivets but in high stress areas Huck bolts are used. I make this statement from experience as an air frame mechanic assembling and repairing DC9's wings at McDonnel Douglas. Hull warranty the manufacture offers gives a good indication of how confident they are in their product. Crestliner, life time on the welded hull. Lund, life time on only the double riveted seams. Alumacraft 20 years on the riveted hull. Also both welded and riveted are subject to material and manufacturing defects.
"Also it is easier to repair a welded hull because you can identify where the leak is and repair it without the need to remove decking "
WHAT??? Who ever conned YOU into believing that? Have you ever welded aluminum? That surface needs to be heated tremendously prior to any weld, Do YOU know what's on the other side of that hull? They ARE and WILL gut that portion of the boat out to get to the other side, guaranteed. Please, please, please, never try to fix anyone's boat.
Yes l have welded my aluminum hulled boat, and yes l did know what was on the other side. But l did have to remove one floor panel but did not required to remove the floor to find the leak. Now with my aluminum boat the only way l could find the leaking rivets was to take out all of the flooring, dry the floor and then float the hull to mark which rivets needed replacing. Next l had to drill out the rivets and then install the new rivets, which takes two people. One to buck and the other to rivet. Please please never try to tell anyone anything. @@BumpNrun69
Welds don’t flex and welded hulls will crack vs riveted hull will eventually leak from loose rivets but easy to fix and will flex under the stress.
IMHO Do what LUND does. Weld where welding works best and double rivet where rivets work best. It doesn’t have to be mutually exclusive.
In the interview and following conversation presented here, I can not help but say that the elephant in the room has been ignored. I would never provide any criticism for the structural component of an aluminum boat as they are well proven. Nor would I argue against replacing a rivet or rivets in an aluminum boat. However, out here in the field as a repairer we see a very large number of leaking aluminum boats, some with loose rivets and some not. The issue absolutely is not the rivets it is the bonding agent used on the seam to increase the strength and seal the seam. It becomes delaminated, and then the boat leaks. You can tighten or replace rivets, but you can't replace the bonding agent properly without totally disassembling the seam that is leaking, which would be cost prohibition . You can seal the seam on its edge, but with the bonding agent nullified sealing that edge doesn't seem to last very long.
The other elephant in the room is how rivets "distribute" the energy of that 1 foot chop. He won't say it, but they ever so slightly move. You can see where that's going...
Okay, both are good ways to build sheet metal boats of thin guage. However, I have experienced one thing that happened to a welded boat, which I have not seen on riveted. I will not name the brand because they are excellent boats. That said, Ihad a 16ft jon wit a very shallow V bottom. Driven by a 35 hp tiller control motor, it was fast, I can tell you. Out on Puget Sound, it can get choppy - not the best environment for a jon with 20 inches of freeboard. And, certainly not teh best environment for a flat running lake hull. As I used it over a couple of seasons, I noticed that the margins at the welds in certain spots were cracking. Not weld itself, but the sheet metal just next to the bead edge. Iassume it was material hardening when it was welded. We're talking .060" sheet - easy to get it brittle.
I went on to use the boat, but cut back my bay running and took it to lakes instead. I was probably abusing it, but I'm just sayin'.
Today I have a 2000 Northwood (Smokercraft Voyager), bought used, and have never had an issue in a chop except for soe pounding because it's so light. No rips or cracks at stress points. SO, I think matelfatigue or process hardening may be a thing with welding very thin aluminum.
a Jon in heavy seas is a bad idea no dead rise to handle the heavy seas glad you got in OK Jon boats are good for small lakes rivers and some smaller bays out on a big body of water bad idea... I bet that was a stressful ride especially with a tiller weight distribution is critical to lessen bow slap. 16 foot Aluminum deep V with a 20-25 degree dead rise at the bow would have been a way different ride.
.060 is very thin for a welded boat, but still the welds didn't fail the material did. I wonder which alloy was used....
@@kenneth9874 T-6061, like all quality aluminum boats. It's hardedned and much stiffer than comon sheet alloy. Used in aircraft bodies. Think: Grumman canoes.
The cracking was my fault, I'm sure. A welded jon will last as long as any good alloy sheet boat if used as desdigned - not wave hopping at 25+mph. I'm talking 2ft waves and large boat wakes.
For the record, the brand was Crestliner, a very good manufacturer. The cracking never got any worse, and the boat was completely satifacory. I would recommend it to anyone.
My Northwood 14 is a completely different design, being a re-badged Smokercraft Voyager, made by a Smokercraft subsidiary. It is a wave cutting design for large open lakes and sheltered bays, and handles chop very well because it has more V at the entry - graduating to a semi rounded transom for planing. Both are excellent boats for their intended purpose.
@@OutnBacker sometimes harder and stiffer is more brittle.....
@@kenneth9874 True, but T6061 has always been the Go-To alloy for aluminum boats in this class and works amazingly well, given the overwhelming number of them that are older than their owners. Aircraft made of it have th same fatigue and cracking issues. If you look very close at WW2 Grumman fighters, you'll see all kinds of quick fix patches riveted on over bullet holes and stress cracks. Russian fighters were much more crudely built, and used lots of soft aluminum, which actually ripped. More patches.
Ive owned a few aluminium boats or tinnys as we call them in New Zealand. My riveted ones had to be re riveted every few years. But my last two have been welded much superior. I currently have a 4.30 side console 5mm hull 4mm sides its great. I dont go out in rough conditions
I have a 16' Quachita purchased in about 1970. Had a Corvair airboat setup on it for several years and then switched to 40hp outboard. Most of the boat is riveted to the hull stiffeners and seats. The bow is welded as is the transom. The only crack developed in the bottom where a bottom groove was formed by pressing I think. Some of the rivets started leaking so I got my son to hold a hammer on the outside while I hammered them flatter from the inside. The only welds that broke were the gussets to the transom on the gunwales. Boat has been well used and still has a lot of life left.
I have a 20 year old Starcraft aluminum v hull that I use primarily in salt water. It doesn't leak a drop and has been perfect for me. It's just a 14'3" but takes two guys fishing in bays and in decent chop with a 25 hp motor and moves right along. I love it after scaling down in steps from longer boats. I'm old now so it's easier to handle alone. 😀
Post weld heat treatment of aluminum is required for optimum strength, planes would be lighter being welded if there was a practical way to build wings, welded and heat treatment without warping etc.
Aircraft grades like 2000 and 7000 series for aircraft can’t be welded. 5000 series of different types are used in marine and welded and left as is.
Couldn’t agree more. I’ve owned a 20’ Lund Alaskan since 98 with high hp tillers and pounded the hull hard over the years and to this day it doesn’t leak a drop. Aluminum hulls have to flex and welded joints are too rigid and will eventually crack. Ask my different buddies over the years who’ve bought new welded hulls and they had nothing but headaches and they vowed never to own welded again. YMMV
Nice part about riveted boat is you dont have to know how to tig weld to fix em
Ive got a 25 yr old riveted 14' riveted boat, always used hard and still dont leak a darn drop. Naden. Canadian made. Im the 3rd generation owner of it and will pass it down when the time comes.
The second time I've visited this same video. The debate goes on, and probably always will. Coming from Minnesota the debate is strong there where you have Alumacraft and Lund riveted boats going up against Crestliner welded hullls all made (or were?) in that state for the same choppy waters and granite bottomed lakes.
Some of the things not being mentioned, and I'm sure there are more when you bring in welded boats of the Pacific NW and southern jon & bass boats and the types of waters they run in, are the other things like improved adhesives between riveted panels and the tongue & groove extrusions some welded hulls use.
Suffice to say, buying from a quality manufacturer with good dealer support and it probably boils down to personal preference.
To compare a welded aluminium boat to an aircraft’s riveted construction is an apples to oranges comparison. The alloy skin of an aircraft is thin to keep weight down and as such would be difficult to weld for starters . Rivet holes are notorious for having cracks migrate from them , but easy to repair with doublers etc . Plus easier to replace damaged parts or gain access ie to inspect inside wings etc .
By comparison most welded alloy boats are 4-5 mm thick and the quality of welds today is impressive . As an example , our 7.4 m alloy boat was built (welded construction ) in 1992 . No welds have ever failed and it’s had a pretty hard life , off the West Coast of NZ . We did have some pitting in the alloy of the hull , but they just cut out that section and welded in a new section and she’s good to go again .
Aircraft grades like 2000/7000 series cannot be welded, it would impact the temper, which is why they use fasteners/rivets.
I about sunk in a late nineties 19’ riveted hull boat I purchased used. I didn’t see any signs of of loose rivets before taking it out. Luckily the auto bilge came on and started draining and I hit it back to the dock. I’ll never own another in that size.
With anything less than 3/16” i can agree
I have experience in work skiffs with 3/16” sides and 1/4” bottoms
And i do think there is an application for both methods
Bottom bracing and framework layout is critical in both applications
Weight and foam for structural integrity is also part of the equation
hull materials, joinery,design, application, maintenance, hp requirements, cost is very end user specific
Thanks for posting!
This!
A sheet metal welded boat is very different from a plate welded boat.
Crestliner tracker lowe are sheet metal boats when welded changes the temper of material at weld location and if any cracks they will start there and spread. Rather have rivets in sheet metal and welded plate. I have both neither leak and each has its applications.
@@omieyouknowme "when welded changes the temper of material at weld location and if any cracks they will start there and spread"...
Finally, someone who is educated enough to understands the chemistry of a weld. Many people here are so clueless to this fact.
@@BumpNrun69 waiting for epoxied aluminum boats.
@omieyouknowme marine plywood, 'glass and epoxy composite hulls are excellent. They're durable, easy to repair, quiet and warm. Plus, wood floats. Kind of makes sense to make boats out of it, but it's not as profitable to large companies as cranking out aluminum hulls.
During the manufacture installing rivets requires less skill than welding. Its a cheaper boat to manufacture if its riveted.
dude thought he was sly saying there was more labor with 2 people bucking rivets. haha. its faster and non-skilled. its cheaper. thinner aluminum is MUCH MUCH cheaper and can be cut, bent in a brake, and riveted. entry level workers with no experience can be trained to rivet in 15 min. application is everything though. if you don't need welded, don't buy welded.
My father bought a Duracraft 1648 DD back in 1996. He put a Go Devil long tail on that boat so we always run it in shallow water. We’ve hit more stumps than I can count and that boat has held up phenomenally well. We have never had a problem with it. I definitely prefer welded aluminum boats over riveted aluminum boats. I don’t think a riveted boat could survive the abuse id put it through.
Its real simple logic.....aluminum boats flex.....welds do not flex....rivets do....
Yep, rivets can create elongation within their the holes. Welded joints throughout time create "weakest link" points scenarios; next to the weld itself. I'll take the "rivet" design any day of the week.
Tell us of battleships and aircraft carriers, or even oil tankers that are rivited. Lol.
@@NoneOfYourBeesWax1 Also you tell us the difference of the Steel and Size of the Steel being used on them application. Big (Huge) difference in applications than a sheet of aluminum hull less than 1/8".
ALL metal flexes.
@@NoneOfYourBeesWax1On the other side, there aren’t any aircraft that are welded. The Titanic was riveted, most early ships were.
The reason aircraft use rivets is because they have no need to be water tight and if a panel is damaged, they can remove the rivets and rivet a new panel in place much easier than welding.
If you are welding, you're essentially making two pieces of aluminum into one piece. It's not as easy to repair, but it is stronger and more water tight.
My aircraft floats are Riveted. Sealant is placed between the joint before riveting. Pressurized aircraft are also sealed in the same way. That sealant can become dis-bonded and our floats leak a little during movement. Our aircraft are riveted because the Higher Strength to Weight Al Alloys cannot be welded. Friction stir welding of our alloys has been tried as a manufacturing process but not widely adapted or field repairable.
Most aircraft are air tight.... they use rivets because the UTS is calculable and reliable. Also, because the heat treatment is lost in the HAZ. pretty tricky to heat treat a whole airplane.
Aircraft grades like 2000/7000 series can’t be welded because the heat takes the temper out of the material. Both grades aren’t great for welding. Most boat manufacturers use 5000 series of various types, these are not heat treated grades
I worked for Boeing and cut sealed and riveted the beauty strip the top of fuselage to the bottom.have to be very careful shooting and bucking rivets
Facts.
I am on my second riveted aluminum boat. I gave up on the first one after it leaked 2” of water into it overnight. The second has not leaked in 10 years. It is an Alumacraft.
I owned a welded Crestliner and a 12” seam split open in the hull. No rough stuff. I checked with the dealer and they called Crestliner and the repair was approved. A local weld shop did the repair and sent the bill to the dealer. We do have a riveted boat as well and no issues with it.
Alot of both , really depends on the quality of the work done by the riviter or welder , weather its monday or friday , quality of mayerial is key to any things man made , but if your builder isnt on top of his or her game then your product suffers .
The stronger aluminum in aircraft are made from Non-Weldable Aluminum Aloys.
The alloys common in aviation are also more susceptible to corrosion. Re-skinning and corrosion repair is common just from condensation or washing with car wash soaps; gotta use corrosion inhibiting soap to avoid problems.
Aircraft grades of 2000 series for the fuselage are clad top and bottom during the rolling process. The clad is usually a 1000 series to provide corrosion resistance.
That Aluma Craft looks very light weight compared to the 5mm plate alloy, full stringer sub floor frame construction and fully welded-in alloy floor on my Australian built boat. I've never seen a weld on my type of craft ever crack.
I bought a new Crestliner aluminum, all welded, boat in 2001. I ran it through heavy waves without having any problems. I think Alumacraft to too cheap to upgrade their manufacturing to welded boats. They are trying to convince potential customers that the obsolete riveting is superior to an all welded aluminum boat. I'm 66 years old and had many boats (aluminum and fiberglass)and the Crestliner welded aluminum boat is the best boat I ever had. ***I say BS to this video.*** Buy the way I don't work for Crestliner, I never had and I will not make any money or benefit from my comment. I giving my honest opinion.
That's cool... one question. Do you think there aren't any Lund owners out there with the same exact experience?
Welded is much less likely to crack then around a rivet. Rivet is actually cheaper to produce than welding due to the time required. But welded is stronger and more watertight. That is why welding is used where strength is required. Trucks use oversize box and riveting for cost and speed of production as they do not need to be watertight.
The weakest part of a weld is the perimeter; NOT the weld itself. In other words the (less than a 1/8") aluminum IS the weakest link.
@@BumpNrun69 And putting hole in it and then filling it with a rivet is even weaker. I did NDT for several decades and know which I would choose every time.
Wrong.
Interesting theory… But as a kiwi aluminium boats are very very popular here, and in a country of 5 million there must be 30-40 companies making them in all shapes and sizes for Southern Ocean conditions from 3 meter “tinnies” to fish palaces with all the bells and whistles for diehard fisherman, and I’ve never heard of any mainstream manufacturers having issues with cracking welds.
Makes a great sales pitch, but a well designed, well built welded hull will give you no problems in any conditions. Go to a boat show here and probably 60-70% of the boats on show, will be aluminium. They’re the fishing weapon of choice. None are riveted.
I was teaching shop in Alaska , a guy had a welded aluminum boat . He found out the hard way aluminum welds are weaker than the parent metal. I patched it till he could get back to where he bought it .
We had 1997 17 ft aluma craft with a 115 johnson. It leaked from the start! Factory took it back. I bought a 1998 crestliner 17 . With a evinrude 115, its top end is 4 mph faster. No leaks no squeeks and used on big water. Lake vermilion!!!
Thicker welded boats are better than thinner riveted boats
But much heavier. In my fresh water shallow lake fishing Lund is king.
No
I had a riveted boat from 1954. It still works. The only issue is it was too small for a 60hp motor.
To me, the pinnacle of aluminum boats are the Coast Guard 45-foot response boat-medium. By pinnacle , I mean if I could have any aluminum boat, I desired, this is the one I would pick. Obviously I would want more luxury than the .mil version, but the self righting ability, hull design, dual 6 cylinder diesel jet pump powered drive. Joy stick controlled. It is designed to operate in 8 ft seas and survive 12 ft seas and 50 knot winds. Is it riveted or welded? AND we all know the government doesn't always pick the best of the best, but instead often pick the cheapest unless there is a reason for the more expensive option. As far as I know, the RBM45 is welded since you can find the CG requirements for repairing any welds online. I assume there is a reason for picking the more expensive option. AND this has no real context except it is a fact and it was a famous ship that sank. The Titantic was riveted. lol
The problem in comparing the two modes of construction is that of build quality and design. Crappy boats have been built using either technique which will then firmly put people in one camp, or another, depending on their personal negative experience. Done properly there is likely little real world difference between the two methods, although personally on smaller boats using thin aluminum, I prefer rivets, just because welding thin materials produces a real chance of compromising the base material and it cracking.
Something that wasn't discussed is water tightness, Welds don't let water through, but rivetted joins do. How is the water kept out?
Riveting will be water tight if the correct materials and installation techniques are used and the pattern of the rivets is correct.
@@johnbrown6189, which correct materials and installation techniques are involved, please?
Your assuming the weld is leak proof. Unless you're there to see the die pen test or X-ray you'll never know.
@@kylecasetta4091, a good weld is water tight. Regardless, this is not the question I asked.
@@TheErsatzMode you're assuming the whole weld is perfect, very few industries hold their welders and welds to that standard. They do have allowance on impurities per 12 linear inches of weld. To say the welder and or the robot will lay a perfect weld from start to finish every time is living in fantasy land. So as I said unless you personally welded and tested the hull yourself. You can't guarantee the weld is water tight. Aluminum welds are prone to crack especially when MiG welded if not done perfectly. You can easily find stories of boats with broken welds with new ones daily.
Seems to me if I have to replace a rivet, Im out a day of fishing, it's going to cost money, and cracked weld is likely to be repaired from inside not out. so not sure why the rivet has any advantage on that.
A closed end blind rivet and some under waterline marine sealant allows you to replace the rivet from the outside. Aluminum has to be prepped properly and cleaned spotless to be welded properly. And it puts a lot of heat in the area. Both sides of the weld should be prepped.
Thinner aluminum sheet is difficult to weld effectively. Manufacturers use thinner material to save money therefore really have no choice but to rivet. They don’t rivet because it is superior, just superior for the material thicknesses they use.
Most river boats that are required to run over and survive rocks, sand, and logs, use thicker formed and welded aluminum sheet/plate. The thicker material allows welding without overheating and burn through like you would see on the thinner material used on riveted boats.
The flatter the bottom the more it will flex too. That is why you need the thicker material as well.
I’ve seen many Jon boats that are riveted start to leak because over time they start to fatigue from flexing so much. I’m talking about the thin walled RIVETED ones. This isn’t because they are riveted, it’s because cheap thin boats that don’t hold up must be riveted because welding isn’t an option on boats that thin.
There’s also the fact that rivets on a boat don’t take 2 years of trade school and years of practice to master. I would say on a production line a hard working unskilled person could learn to rivet fairly quickly where as putting out a “stack of dimes” is very difficult therefore a competent welder would cost the manufacturer much more.
Laser welding does fantastic on thin aluminum.
the smaller Starcraft riveted boats held up fine for decades but would leak unless the rivets were re-bucked. the larger ones, 20 ft and over were prone to cracking along the bottom between rivets. we have a 1967 Starcraft 14 foot and it's still doing great.
I have 71 15' Starcraft Runabout all good except where the previous owner let it rub on the rocks , got that repaired , been 30 years no leaks.
I never weld cold Aluminium. I insist it must be pre-heated before being MIG or better still, TIG welded. Yes this takes time and costs more. That is why some do not bother pre-heating.
Actually bolts/welds are used instead of rivets nowadays on structural steel. Steel is a different beast.
Way back like the building of the Empire State Building they used hot rivets I believe. Probably more expensive but will last forever.
Got me, Will always prefer an Aluminum boat. If'n had the $. Would get Lunds biggest boat they make. Maybe 1 day they will make 24 footers.
My polar kraft bass boat is riveted and my concern is in future having to possibly remove flooring with new carpet to replace rivets. And welded boats that are painted. Will have to be touched up.
I have owned 15 fishing boats. A long time ago, I.bought an aluminum boat that had been used strickly in salt water fishing the bays in Texas. Every rivet on the boat leaked. I.coated the bottom with polyester fiberglas cloth and resin. Never leaked .a drop after that. I now own a 16' 8" Tracker. I.bought it because it is light, and was inexpensive. I fish small 1000 acre lakes that rarely get any chop on them. If it is windy, I don't go. I hate fishing in the wind. I bought aluminum because they are lighter, require less maintenance, and since I usually fish alone, are much easier for me to manage. When gauging toughness, I look at what they use in Alaska. Their boats are all welded aluminum. All.of them.
Lunds are very popular in Alaska, Canada, and Minnesota on big lakes. They are riveted.
@CaptPeterson Do not forget Polarcraft. My Dad had one for well over 30 years until he passed. The point is you could run that boat up onto the rocks and pound the dents out of the boat, and she was good to go.
There is absolutely no comparison to the stress loads between a fighter jet and a boat. For one, a jet has riveted panels specifically so they can be removed to access interior repairs.
Jets don't bang their way through the air the way a hull bangs across rough water.
Welded hulls are more rigid and therefore stronger. Riveted hulls flex. Metal that flexes succumbs to metal fatigue sooner.
That said, a riveted boat is fine for small waters not subject to significant chop and waves.
Wrong on pretty much everything.
I’ve had several welded aluminum boats (and pontoons) and never had a leak. When I was young, we had several riveted John boats and they all eventually leaked
I have a 1987 Alumacraft with a 60 hp hand tiller and it does not leak after being used every week.. That is 37 years of use....
I had a 1980 Monark 1448, riveted hull with Welds on each side of the bow... I don't remember how many times the WELDS Failed and had to have the welds repaired. Riveted portions never failed!
Properly executed welds on material of proper thickness are fine, but not all fabrication is the same.
@@Comm0ut I had the same problem with an old Fisher Marine. Boat leaked so bad from rough water that I filled it with water on the trailer to find the leak and it looked like a boat shaped shower head.
It depends on size of the boat and material thickness
I always worry about stresses while going down the highway with a load of gear in the boat. I don't beat on it too much fishing lakes.
I have a 2021 Alumacraft that takes on some water. What can I do?
Partially fill it with water on land to determine where it leaks.
I had a Crescent liner split a weld, suppose to be a life time warranty. Took it to the dealer, they talked to the factory, approved it and the dealer paid the weld shop. It was 5-6 old at the time.
Ever since the Titanic sank I have been sticking with welded boats. I would not take a riveted boat anywhere near an iceberg.
@brittseverence7221 i dont think thats the reason it sunk, it would've sunk even if it was welded with such impact only a thicker hull would've survive the iceberg
Lol
@@victormiguelmontero136 I thought my sarcasm was blatantly obvious. Oh well, not everyone shares my dark sense of humor.
Ironically, the likely reason the Titanic sank so easy was due to heat fatigue of the metal from the coal power plants. The same thing can happen if a welded boat is not welded properly. Although, probably not often
Titanic was an inside job. Lots of important people on that boat and lots of fail safes suspiciously disabled... look into it
Comparing plane and boats is further than apples and oranges... types of stress, vibrations, etc are completely different. Fiberglass boat builder with 40 years experience and also have owned a few smaller aluminum "skiffs" - smaller boats under 18ft for lake use in short interval wind chop = 100% riveted will outperform in most cases ... when you get into larger scale BC/Alaska ocean boats from 20ft-40ft - you will see 100% welded 100% of the time
I've had two riveted boats and both started leaking on the place where the studs from the trailer had contact. It's not so much the bumping on waves but it's the transport on a trailer that causes leaks. I own now a welded made in Finland Buster boat for many years and the quality and performance is not comparable with Aluma Craft etc. I should have bought a Buster from the beginning than i saved a lot of money and trouble.
Riveted boats leak from heavy waves over time. Welded boats don’t but are more expensive initially. Welds can crack however if they are not done properly. Not all welded hulls are equal
This is the only comment I found addressing LEAKS. 99.9% of boats are plenty strong enough in the conditions they were build for.... Over time, rivets leak. I like a dry boat.
Airplanes are Riveted because of dissimilar metals. The F14 was specially treated with 6000-grade aluminum with a titanium structure. We Rivet because you can't weld them. Some of the new stuff is heading to composite epoxy laminate.
BS for 500 Alex. Tell me you are not an A&P without actually saying it…
It's not BS. I've seen the whole fuselage on that plane. It's basically the same process boing uses to make all their s***.
How so?
Try and find a welded fuselage on any aircraft, not gonna happen . Standard practices are approved by the FAA …a titanium Hilite is stronger than any weld
My point was you can't weld aluminum to titanium or other dissimilar metals. Also, some of the aluminum used in airliners are in either the 2000 or 7000 series of alloys and they are considered to be non-weldable. There are plenty of world war II, p2s that have fully welded aluminum fuselage. I've seen one fully restored. All welded and polished to a mirror finish, it's really a sight to see.
The main alloys used in aircraft construction are heat treated and usually not considered weldable. So bringing aircraft into the discussion is misleading because they have to be riveted. The only places you will normally see welded aluminum in aircraft are for items such as tanks, or non-structural fairings. Since those components are not as highly loaded, lower strength, weldable alloys can be used.
Tanks are water tight I’m assuming. That’s kinda the point I’m taking away.
@@colt110987 Being water/air/fuel tight doesn't really have anything to do with welding vs. riveting. Many tanks are riveted, and an integral part of the structure, more so the larger the aircraft gets. On light aircraft, there is less advantage to having the tank built into the structure, and since they only have to support the weight of the fuel they carry (as opposed to being part of a wing's primary structure), then it's just easier to make them out of a lower strength alloy and weld them.
Also consider that many aircraft made of riveted structure have to be airtight because they are pressurized.
I had an xpress bay boat. I had the welds fail three times and different places. Never had a riveted hull but I will never buy another xpress boat again
I had welds fail as well.
@ was it an x bay? I’ve talked to a couple people here in south Louisiana that that particular one seems to have problems. If spread doesn’t cover it under warranty it’s crazy expensive. They had to take off part of my upper deck to get at it inside and from the bottom
I have a 1988 v16 alumacraft riveted boat I’ve owned it since 1990. It has never leaked. I replaced 2 rivets where the seat brace meets the seat. I don’t honestly think it makes much of a difference.
aluminum can be heat treated and it becomes a lot stronger and tougher. when you weld it you ruin the heat treat. this is why airplanes are riveted.
Rivits disperse the load across an area the diameter of the rivit at each rivit point.
A weld spreads the load evenly along the length of the seam.
At the point of failure a popped rivit transfers it's load to the next rivit which wasn't designed for that load.
The rivits start popping like a submarine movie.
This leaves holes where water jets in.
We'd have to try to break our welds in shop class and the weld should be stronger than the surrounding metal.
A poor weld can erode the surrounding metal and create a thin spot. Heat can harden the metal and make it brittle.
Modern robotic welders sure make some pretty welds and rarely over cook it.
on my second welded boat been in rough seas many times landed hard many times no issues tired of rivet guys saying welded boats crack that's BS I think both are good and its a stupid discussion and air planes have big temp and pressure changes that's why its riveted pretty sure a boat will not see the kind of changes a plane will see.
You don’t have to always use two people to buck a rivet. There are many tools out there like squeezers and alligators with various reaches.. Spend the money on the right tools and you’ll save money in the long run
Riveting is way cheaper and just as good.
Most game wardens will tell you that all drowning victims thought they had gills like a fish, and that is why they didn’t wear life jackets.
I have a 2001 sprint marine ocean pro and ive beat that boat up many years still running strong welded boat on the colville river i live in Nuiqsut Alaska
My dad had a Quintrex welded boat and yes it developed a tiny leak at the weld
I will stick with a welded boat despite what this 2nd generation riveted boat builder says. Every riveted boat over time ends up leaking eventually. Good luck pinpointing the leaking rivets.
Welded with superior filler , This guy has an biased opinions that is not what I want.
Its fine in fresh water. Wont last a month on gulf coast in the chop
There is nothing wrong with a well built riveted boat, or a well built welded boat. Both methods have beautiful functional examples.
The British can tell you about rivets because they stopped using them on their tanks in WW2 because after an impact they would pop and kill the crews in the tank.
I would never own a aluminum shower stall on the Great Lakes.Love my Ranger.
It’s all based on the thickness of the material thin aluminum needs to be riveted, but please understand that mega yachts, which are hundreds of feet long use sticker aluminum and they are welded and weld because the material is thick enough
aluminum becomes weaker when exposed to heat from welding
Really depends on the quality of work being done to build the boat. A skilled riveter will make a better boat than a poor welder, and vise versa
What about these new big offshore catamarans that are out there on the market?
I wonder if they can take the stress of big wave over time?
For sure.
I've had rivets come loose and leak on aluminum boats.
Flexseal
The first aluminum boat I owned was a leaky pos after a few years. "riveted hull". I sold the piece of junk and bought a welded hull boat. The person up front never had to "Bail Water" all day any more. If you plan on owning the boat for a long time DO NOT buy a riveted hull. You'll be sorry.