One way to provide flotation while allowing the boat to dry out would be to attach the bench seats to the ribs in the floor and sides rather than attaching directly to the sides and bottom. My plan is to make a built in cooler in the middle of the addy section bench with two compartments on either side filled with two part expanding polyurethane foam. This should be plenty for up to a 20hp engine. Then again at the middle seat to compensate for the battery and again in the bow to compensate for the anchor and trolling motor. The area below and to the sides will have air flow so even with a bottom on the bench the hull will dry out. At most the bench might eventually rot because I plan to cover the top and sides with fiberglass but it can be replaced fairly easily if rotting becomes an issue. Sure wish I could run this by Jeff. RIP 🙏
My boat mechanic recently gave me a big old spiel about foam taking on water and weighing tons. He said you’re better off using old 2 liter bottles (probably encased in boat foam) than just foam alone. Makes a ton of sense.
As always Jeff great video. and thank you for explaining the logic behind floatation. I've considered building my own boat for a very long time. the down side for me is my boat I want to build is 15'X60' wide body narrows boat. finding a boat yard to rent the space to build from scratch as become quite the issue for me. everyone I've talked to says the same thing. If its already built and I need a haul out they have space. other wise they don't have time or space. and doing a backyard build for a boat that size isn't really a logical move in the right direction either.
Thanks for all these videos, they are really helping me out in making a decision. I'm 28 and have always canoed and kayak fished all my life, BWCA and some white water kayaking too. I've been wanting a little jon boat for the lakes out here in MO, I have a old Sea King/Clinton 7hp 2 stroke I inherited but know I want a 25hp for hitting the mighty mo. I don't feel comfortable with budgeting a new 25 with as much boat as I can get which would be a 1542 jon. I did a little research into building one which led me here and I feel much more comfortable in the prospect of building the 16' Garvey Dory and being able the get the boat I want with the engine to push it as well, without having to compromise. Hopefully I can make a winter project out of it soon. Kind regards, Chris St. Clair
Thanks for the info much appreciated... I have a 22ft fibreglass boat that has wet foam... so if we remove and replace with air compartments only if water gets into one of these compartments how can we get the water to get to the back drain plugs?
You have answered all of my questions about flotation so my next query will be the tag that tells maximum horsepower and how much weight or people the boat can carry and is this tag even a requirement on a home built boat. So far I have learned just enough about it to really confuse me. Thanks Jeff I always enjoy your videos...
I have other videos about those. Here's the one about loading: ruclips.net/video/HG7grY9qzCI/видео.html And this one is about the horsepower: ruclips.net/video/BuuGdpBAaBE/видео.html
Mr. Spira please, I had read a brief comment you did once in facebook about your system of navigation, I remember was simple and efficient. Can you do a video about? Thanks.
@@tjkid07 thank you, still watching your video about Brendan now. I was interested in currachs but I believe your modern dorys are the heirs now, because bouyancy and flat bottom.
I’m hopeful that you will do more videos or information on the 27 mullet skiff.how seaworthy/ Blue water add on s you may make it different.I would like to build a live aboard 27-28 ft for cruising.with outboard motor set up if possible.
How seaworthy? If you're a experienced and careful skipper, extremely seaworthy. If you make bad skippering choices and have no idea what to do when things happen, then not so seaworthy. How's that? Where do you want to go? You said outboard, how big/fast? How much fuel? How much water do you think you could cross with how it is set up? Looking for an all weather boat or a fair weather boat?
I was in a small pontoon with a few people following the Branson Belle, on Table Rock Lake, the bow sunk to a depth where the front deck was awash. Once the pontoon backed off the Belle it returned to normal. What causes this?
At 5:20 you say people think the boats "float higher" with flotation. What about a boat that is swamped (i.e. a small sailing dinghy that flipped and has been righted). Can you "float" the gunwales high enough that you can bail or pump out the boat? Thanks.
If it is full of water? Yes, it will float higher as the flotation is trapping air underwater. If it is not full of water, it will not float higher, it will actually float slightly lower, since the flotation is not only air. I hope I understood your question.
Thank you Jeff for the information. Question: Do compartments with watertight hatches when used for storage of gear retain most of their buoyancy? I am looking at your 19' Alaskan Grands Bank Dory as a possible camp cruiser and would like to plan gear storage. Thank you for any advice.
Earlier in the video you said that no matter what you do, water will get in and rot your framing (if you don't drain it out). But at the end of the video you were saying the best flotation is not foam, but trapped air. How can you trap air but not water ?
Yes, you can trap water as well as air. Is this what you're asking? I was in general referring to water that comes in over the top, like splash and rain. If you puncture the hull in a boat with a sealed deck, the trapped air will supply your buoyancy and keep water from coming in very much. Is this what you're asking? Perhaps you can explain your question. When I was talking about trapping water, I wasn't talking about enough water to sink your boat, only (fresh water) moisture saturating the wood which WILL cause rot. I always recommend drain plugs to allow and water in the bilges to drain and allow the wood to dry out. Here's more on the insides: spirainternational.com/tipsandtricks/200601_finishing_the_insides.html
Rest in peace, it looks like you passed away sometime in late 2021 early 2022 & someone has pirated your website since then. So sad, some people. Mr. Spiral you are/were an inspection to me
So is your recommendation for the flat bottom boats (no self bailing decks) to just have a drain plug at the back for when your done boating for the day or do you want a bilge pump near the stern too? Then ping pong balls for flotation? They burn pretty quick. ruclips.net/video/bgXYlzKgHbc/видео.html I figure I would need around 4500 balls to get me over 305 lbs of net buoyant force for a 50 hp and 2 batteries. That above video is 5000 of them burning. No fun.
That many pounds of styrofoam will burn about the same. I don't seem to recall saying that you have to use ping pong balls, just suggested that some have done that. Yes, add drains to the boat, and, yes, add a bilge pump if you feel like you need it. You know what they say, the best bilge pump in the world is a scared sailor with a bucket.
Masan, RUclips has this great feature called scrubbing. If you don’t want to listen forward the video a bit. Thanks Mr. Spira for all the resources you provide. I’m the one building the Caladesi with the white oak frames
All very good information. RIP Jeff you were a good man…
Thank Jeff for your " Spira Boats "
RIP. Love the description of the dead head log. Go right through a steel hull even.
Yes he will be missed. Unfortunately I never purchased any of his plans.
I’m so bummed I missed my opportunity to connect with Jeff. Rest in peace. ❤❤
Once again, Jeff answered one of my many concerns again in another informative video. Thanks Jeff
One way to provide flotation while allowing the boat to dry out would be to attach the bench seats to the ribs in the floor and sides rather than attaching directly to the sides and bottom. My plan is to make a built in cooler in the middle of the addy section bench with two compartments on either side filled with two part expanding polyurethane foam. This should be plenty for up to a 20hp engine. Then again at the middle seat to compensate for the battery and again in the bow to compensate for the anchor and trolling motor. The area below and to the sides will have air flow so even with a bottom on the bench the hull will dry out. At most the bench might eventually rot because I plan to cover the top and sides with fiberglass but it can be replaced fairly easily if rotting becomes an issue.
Sure wish I could run this by Jeff. RIP 🙏
My boat mechanic recently gave me a big old spiel about foam taking on water and weighing tons. He said you’re better off using old 2 liter bottles (probably encased in boat foam) than just foam alone. Makes a ton of sense.
That's a good idea
Thanks!! Great information!!!!
Great talk and video Thx :)
As always Jeff great video. and thank you for explaining the logic behind floatation. I've considered building my own boat for a very long time. the down side for me is my boat I want to build is 15'X60' wide body narrows boat. finding a boat yard to rent the space to build from scratch as become quite the issue for me. everyone I've talked to says the same thing. If its already built and I need a haul out they have space. other wise they don't have time or space. and doing a backyard build for a boat that size isn't really a logical move in the right direction either.
Thanks Jeff your videos are very nice at really late hours
Jeff, I would like to request a video on your Deadrise boats....Tangier and Pokomoke.
Thanks Jeff. Very very informative!
Thank you Jeff!!! Very informative!
Thanks for all these videos, they are really helping me out in making a decision. I'm 28 and have always canoed and kayak fished all my life, BWCA and some white water kayaking too. I've been wanting a little jon boat for the lakes out here in MO, I have a old Sea King/Clinton 7hp 2 stroke I inherited but know I want a 25hp for hitting the mighty mo. I don't feel comfortable with budgeting a new 25 with as much boat as I can get which would be a 1542 jon. I did a little research into building one which led me here and I feel much more comfortable in the prospect of building the 16' Garvey Dory and being able the get the boat I want with the engine to push it as well, without having to compromise. Hopefully I can make a winter project out of it soon.
Kind regards,
Chris St. Clair
Lots of my builders use 25s on bigger boats including 19 and 20 footers, like: ruclips.net/video/iYd2cUwq2z8/видео.html
Getting pooped isn't fun, lol. My favorite is your drop ramp dory, the mini Higgins, only because I always wanted to take a motorcycle. Thanks!
Thanks for the info much appreciated... I have a 22ft fibreglass boat that has wet foam... so if we remove and replace with air compartments only if water gets into one of these compartments how can we get the water to get to the back drain plugs?
Excellent....thanks!
You have answered all of my questions about flotation so my next query will be the tag that tells maximum horsepower and how much weight or people the boat can carry and is this tag even a requirement on a home built boat. So far I have learned just enough about it to really confuse me. Thanks Jeff I always enjoy your videos...
I have other videos about those. Here's the one about loading: ruclips.net/video/HG7grY9qzCI/видео.html
And this one is about the horsepower: ruclips.net/video/BuuGdpBAaBE/видео.html
@@tjkid07 Thank You Sir...
Mr. Spira please, I had read a brief comment you did once in facebook about your system of navigation, I remember was simple and efficient. Can you do a video about?
Thanks.
I was planning to add a series on Seamnanship, Boat Safety and Simple Coastal Navication. I used to teach a class on it.
@@tjkid07 thank you, still watching your video about Brendan now. I was interested in currachs but I believe your modern dorys are the heirs now, because bouyancy and flat bottom.
I would also like to see a video explaining displacement as it relates to your designs.
No problem. Here you go: ruclips.net/video/HG7grY9qzCI/видео.html
@@tjkid07 Thanks Jeff. I'm trying to figure out how I missed this one. 😁
I’m hopeful that you will do more videos or information on the 27 mullet skiff.how seaworthy/ Blue water add on s you may make it different.I would like to build a live aboard 27-28 ft for cruising.with outboard motor set up if possible.
How seaworthy? If you're a experienced and careful skipper, extremely seaworthy. If you make bad skippering choices and have no idea what to do when things happen, then not so seaworthy. How's that? Where do you want to go? You said outboard, how big/fast? How much fuel? How much water do you think you could cross with how it is set up? Looking for an all weather boat or a fair weather boat?
I was in a small pontoon with a few people following the Branson Belle, on Table Rock Lake, the bow sunk to a depth where the front deck was awash. Once the pontoon backed off the Belle it returned to normal. What causes this?
At 5:20 you say people think the boats "float higher" with flotation. What about a boat that is swamped (i.e. a small sailing dinghy that flipped and has been righted). Can you "float" the gunwales high enough that you can bail or pump out the boat? Thanks.
If it is full of water? Yes, it will float higher as the flotation is trapping air underwater. If it is not full of water, it will not float higher, it will actually float slightly lower, since the flotation is not only air.
I hope I understood your question.
@@tjkid07 Exactly what I was looking for and what I assumed. Of course the trick is to raise it higher than the swell!
Thank you Jeff for the information. Question: Do compartments with watertight hatches when used for storage of gear retain most of their buoyancy? I am looking at your 19' Alaskan Grands Bank Dory as a possible camp cruiser and would like to plan gear storage. Thank you for any advice.
Yes, they retain all of their buoyancy, except if you poke a hole through them.
@@tjkid07 Went ahead and ordered the plans for the Alaskan. Now to get started buying materials. Thank you for the quick reply. Take care.
@@mattevans-koch9353 Thank you Matt, Please keep me posted on your progress.
Earlier in the video you said that no matter what you do, water will get in and rot your framing (if you don't drain it out). But at the end of the video you were saying the best flotation is not foam, but trapped air.
How can you trap air but not water ?
Yes, you can trap water as well as air. Is this what you're asking? I was in general referring to water that comes in over the top, like splash and rain. If you puncture the hull in a boat with a sealed deck, the trapped air will supply your buoyancy and keep water from coming in very much. Is this what you're asking? Perhaps you can explain your question.
When I was talking about trapping water, I wasn't talking about enough water to sink your boat, only (fresh water) moisture saturating the wood which WILL cause rot. I always recommend drain plugs to allow and water in the bilges to drain and allow the wood to dry out. Here's more on the insides: spirainternational.com/tipsandtricks/200601_finishing_the_insides.html
Rest in peace, it looks like you passed away sometime in late 2021 early 2022 & someone has pirated your website since then. So sad, some people. Mr. Spiral you are/were an inspection to me
Watched the entire video and I'll summarize for those who don't wanna watch the full video....TRUST THE DAMN BOAT Its Designed to work
Built and registered a homemade vessel. Not once did I have to show anyone floation or have it inspected by anyone.
So is your recommendation for the flat bottom boats (no self bailing decks) to just have a drain plug at the back for when your done boating for the day or do you want a bilge pump near the stern too? Then ping pong balls for flotation? They burn pretty quick.
ruclips.net/video/bgXYlzKgHbc/видео.html
I figure I would need around 4500 balls to get me over 305 lbs of net buoyant force for a 50 hp and 2 batteries. That above video is 5000 of them burning. No fun.
That many pounds of styrofoam will burn about the same. I don't seem to recall saying that you have to use ping pong balls, just suggested that some have done that.
Yes, add drains to the boat, and, yes, add a bilge pump if you feel like you need it. You know what they say, the best bilge pump in the world is a scared sailor with a bucket.
Commandants Publication=CMDTPUB.
Dont long speaking..just must go on how to built boat..so bored long watch speaking..
OK, I'll try more short speaking, and tone down my long speaking?
Masan, RUclips has this great feature called scrubbing. If you don’t want to listen forward the video a bit. Thanks Mr. Spira for all the resources you provide. I’m the one building the Caladesi with the white oak frames