If you look at 'Refit and Sail' episode 15, you will see how both George and I have done our engine beds. Using the angle iron means the bolts can't pull out of the timber bearers. Pretty well bullet proof in a roll-over, clamp the angle to the bearers and adjust the engine angle before cross drilling the bearers. You will need to suspend the engine on a ratchet block to make it easier for yourself. You do need to match the prop to the engine horsepower/engine revs/gearbox ratio.
Our prop shaft snapped a couple of years ago. We found a prop shop who had a good selection of used shafts and propellers. It was a lot cheaper than new to have a used shaft shortened and a new key way and threads cut.
Yep, funny job to do wth engine. I have a gap between rope cutter and strut of 25 mm for a 30hp engine, between 12 and 14 mm are used for the elasticity of engine movement since I have no thrust bearing. But what I definitely would like to recommend is the rope cutter which I needed 3 times for max 16 mm ropes. Unbelievable that the cutter is able to cut ropes of this diameter. You are doing a fantastic job, I'm following you since the very beginning. All the best furthermore!!!!!👍👍👍👍👍
The engine installation is an exciting step. The propeller thrust causes forward movement of the propeller relative to the strut due to deflection in the rubber engine mounts and possibly some movement within the transmission. I measured at least 7mm between idle and full power on my yanmar 3ym30. It's bad news if your rope cutter hits the back of the strut. Suggest talking to the engine manufacturer about the minimum allowance.
I think you should let the shaft protrude 50 mm + from the cutless befaring. You should also take info account the distance from the propellerblade to the hull. This should not be to little, as to avoid redusere turbulence. I think it’s wise to leave cutting the shaft till you’ve decided exactly where the engine will sit (obviously).
The engine, heavy as it is, makes up a very small percentage of the displacement. So don't drop it on your toe but don't sweat a little weight change either. As you have pointed out, if the output shaft is going to line up with the prop shaft, the heavy bits will be in a pretty similar place.
When “encouraging” the ends of threaded shafts/ bolts with a precision hammer, I like to thread metal nuts on the end threads to protect them if I strike the end of the threads. When you remove the nuts, they tend to “rethread” the the shaft/bolt. Thx for bringing us along.😊😊😊 John Ken
🤣🤣🤣 We've had intros before. Marina made a water colour of our trip on the canals. Tbh it wasn't planned to be an intro but many liked it so Marina used it again. I think it seems to work. Hope you enjoyed it. Cheers for watching 🙂
Just looking back at the start ,I would never have taken on the challenge, didn’t even think it was viable,you have done well, Marina is right to question the prop size and pitch, very important
We have tried looking for definitive answers on propeller sizing, but we are only getting approximate ranges... The propeller is within that range. We'll make some more inquiries. Cheers for watching 🙂
You should have a propeller fitting with your transmission ratio. the clearance between your propeller and your hulll should respect a minimum value to avoid turbulances. You should wait for the new shaft before fixing the strut. When you will try your shaft you could ad a rubber section around the shaft to be fully center of the stern tube (bicyle handle and tape was ok for me) . if you go with a second hand shaft be sure it s pro inspected to have something straight and perfectly balanced. the stern tube is a replacement or the original ? laminate reinforcement at the base could be an idea.
Thanks for the tips! Laminate the base of what? Orginal stern tube.l, new shaft, the propeller I think is in range. 56hp engine, 2.36:1 gear ratio, 22000lbs weight, 33ft lwl. 18x13 propeller... The only thing left to source is a shaft seal. But, slowly slowly it's coming together. Cheers for watching 🙂
That engine base looks so clean! I removed my engine some days ago and now have first time access to my bilge. Identified two pumps and a strange construction containing two switches. Only one pump works. All covered in and between a black swamp :-) Have to clean overhead with a stick as my bilge is very deep. If i fall inside onle my feet will bee seen 🤣 So you are far ahead of my progress stu! Have i mentioned my engine sat on four rusty "things". Have to inspect the next days... So much fun to look your videos. Kind regards Thomas
Engines bilges are never nice place to work. I hope we can keep ours clean, easier when it is clean... We think/pray that if we stay on top of the maintenance, our bilge might stay tidy and oil free. Best laid plans. 🤣🤣🤣 Good luck with your engine. Cheers for watching 🙂
Yup, classic boat life. "...oh, this needs fixing" But step by step. We could find a second-hand shaft. The only thing needed is a stern tube gland/seal thing... Thank you for your comments. 🤩 Hope all is well on your boat. Cheers for watching 🙂
@@SailingSeabird yes, indeed. 😂 Good ol’ stuffing box. Dripless? Or…that other kind, the older, traditional style, which we have.. We’re having trouble pulling the trigger on the clamps. Very important, those clamps. 🤔😆 Another winter in the yard. Our diesel heater goes back with us this weekend. Keeping on. 😆❤️ 🥰🤗😎
Hope you get the leaks fixed before very long and although it is depressing, at least the rain was nothing like Valencia. I'd guess the greater the distance between the bracket and the prop, the greater the risk of flex in the shaft, so although the load going through the prop isn't going to be massive when everything is running normally, a shorter gap would be better than a long one as long as the prop can clear the bottom of the boat. All the best!
Rope cutter a must saves you going over the side at 2 in the morning cold water, jelly fish sharks. Plus boat will be moving up and down very dangerous whack on the head or worse get hit by the prop.
Watching the amount of water that came in the open filler hole, I had an idea. For the water filler, inside the hull, have a diverter "Y" that you select one way to fill water tank (drinking water), or switch the other way to capture rain water in a tank for washing.
Hi Marina, You are absolutely right, you need a zinc anode around the shaft before the propellor. What I last episode forgot to mention, is that you should not sand the copper coat before you know when you are going into the water. We were to long on the dry last winter (approx. 8 months) and we really could say that we should have resanded the copper coat. So yes, you should sand the copper coat but not too long before you splash your boat or you can do it again. We will do that at the beginning of next season when we have to get the boat out the water for the antifouling on the propellor.
One consideration is that the prop should be spaced from hull at least 15% of diameter of prop. If you decide on a larger prop later you might nor have enough room . ( 15% clearance stops prop noise). Also fyi prop shaft should be slightly offset from straight to compensate for the prop walk Cheers warren
Have you watched the new engine install by "Sailing Magic Carpet"? Of particular interest may be the video "installing a thrust bulkhead - why we need it" from about 5 months ago? they discuss the energy (thrust) and force generated every time the propeller shaft is put in gear and how the force to transfered to the gearbox. It might give you ideas on how you want to proceed.
Reading the comments sounds like the rope cutter is a must have....don't cut corners you may regret later. The weather looked terrible at the start of the week, but identified like what Stu said, what jobs the boat needs done....and not what you want done.
Standard and metric prop shafts have specific threads, per shaft diameter. Tapers, as well. Oh, lap the prop, to the shaft, before installation. New shaft HIGHLY recommended, as well as shaft coupling. Best wishes.
Keep going guys ... 5 go sailing, had to haul out there boat to check a P shaft leak.. the seal was with glass and a bump had broke the seal.. When you seal yours fit a sandwich inside to brace it and use a sealant that remains slightly rubbery flexible to avoid that sort of leak developing.
I have gone through installing a new engine, shaft and propeller. Here are a couple of comments. 1) As far as the spacing between the propeller and the "P bracket" standard practice is to keep it to 1.5 times the shaft diameter or less. Since you are installing a 30 mm shaft, that means keep the distance to 45 mm or less. 2) Sizing the prop s quite a bit more complex than it might seem at first look. The idea is to size the prop (diameter, pitch and blade type/number) so that the engine can get to just above its rated rpm at full throttle. For example, if your engine has a 3,000 rpm rating at full throttle, you would like the engine to be able to get to say 3,100-3,200 rpm at wide open throttle running on flat water. The prop parameters that matter are: diameter, blade count, disc area ratio (area of blades divided by the area of a circle with the diameter of the prop) and the transmission gear ratio. Pretty much any prop shop can give you a good estimate for a specific prop. It is a good bet that you will need to have a second hand prop repitched. A rule of thumb is that a prop can normally be repitched by +/- 2". There are ways to very accurately calculate the pitch for a specific prop from the details of your hull (waterline length, waterline beam, wetted surface area (including the keel and rudder), depth of the hull exclusive of the keel, waterline area and displacement. You would also need to know the maximum cross sectional area of the hull above the waterline including the cabin house and mast. Finally you need to know the displacement. A naval architect or good prop shop can then calculate the required prop pitch very accurately. There are other less accurate methods that don't need as much calculation, but they often require repitching the prop after a sea trial (more money). Here is a link to a video that discusses prop sizing. ruclips.net/video/eYjmL7fhZEU/видео.html Here is a link to the method I used to calculate power required to move the boat as a function of speed - ruclips.net/video/VxDWt-jFC9g/видео.html
Hi Syu, i had a lot of vibrarion problems with my drive and I learnt a bit about shaft drives. With the P bracket, you should fit the prop as close to the bearing as possible. Also if you can afford it fix flexuble coupling between the gaer box and shaft. Good luck, I used Vetus marine, they have recommendations for prop installations.
Re leaks,, you know for fighter jets, they do a 'leak test' after a long layup, often using a fire engine to spray water under high pressure at the access panels and cockpit etc and yes they sometimes leak more than you'd think! So well done on your 'water shower' test and now you know what's leaking and what's not! You couldn't do that in the hangar.
Fiberglass repairs, will go bad from the sun if not painted. So maybe cover or paint the repairs.You two have come a long way,from the buying of the boat ! Crack on
Yeah, that "fill" job on the plywood looks good. But, I'm worried about the build-up on that engine bed breaking off with the vibration of the engine. I doubt fiberglass lamination would be good enough. What I'd recommend is getting two pieces of "H iron" that would sit on what's there like a saddle, through-bolted on, and provide a channel to hold the buildup pieces, those also through-bolted. That'd be real strong. Even adjustable if you had an engine change down the line. Give it some thought, eh?
Yes you can do it all inside but then you have to take it out and you will find out if all is ok normally no it’s not but you won’t know until it rains
I believe the rule of thumb for the gap between the bracket and the prop boss is; the m 18:12 aximum allowed is no more than 1.5 times the shaft diameter. If you fit a nut which incorporates a sacrificial anode it might be worth fitting a rope cutter between the prop and bracket so make sure there is enough clearance without restricting the flow of water through the bearing. The criteria which affect prop. selection are as follows. Engine HP, gear reduction ratio, shaft speed, hull design incl. length at waterline, shape and design speed. The water exerts pressure on the surface of the blades, too much can cause cavitation and excess slippage if the surface area is too small. The surface area is affected by the number of blades, the shape of the blades, the disc area ratio, or relationship between surface area and diameter. The pitch is the theoretical distance the prop travels through the water during during one revolution. Multiply this by the shaft speed (RPM) X60 will give you the hull speed in MPH. A certain amount of slippage is to be expected.most props are overpitched to a degree, but too much pitch will prevent the engine reaching maximum revs. A prop which is too big will overload the engine cause black smoke, overheating and rapid wear. Propeller design is a dark art, even the experts often get it wrong. The prop you found is an equipoise type normally found on high speed craft capable of planeing, it has a higher disc area ratio than normal and would probably cause excessive drag under sail, thereby slowing the boat down.
Hello again. Another good video of your progress. I thought in a previous video you had a new prob shaft? Are you considering if a folding propeller will fit on your boat? Ok, looking forward to next weeks video. Ciao. geo
We ask the local professionals here all matter of questions. They are a great resource. Plus researching what we can. There are so many companies that will give you a little bit of help and advice. But we like to do the work ourselves, we need to know how to do the job. Cheers for watching 🙂
For Stopping Leaks While It's Raining, (which it's doing a fair amount here on Van Isle). I experimented with a method for plugging any size or shape of hole, I use Gorilla polyisocyanate based glue (its the one that looks like liquid honey) I use almost any thing as a thickening agent, like sawdust, silica sand, bicarbonate soda, micro beads, etc... Just start with a dry substance. After mixing the glue and chosen filler to the desired consistency and the thicker the better. Back up say a 2'' hole in deck with a piece of polyethylene sheet or closed cell foam propped in place with a plywood scrap. Just before filling the hole spray or add a few drops of water and mix some more, also if it's not raining, moisten the walls of the hole. This will activate the expansion properties of the glue, filling in any lateral holes or cracks in the main hole. A golf ball size of mix will expand to tennis ball size. After about 3 hrs The final patch will stand proud of the hole or crack and can be sanded flush. In the case of using silica sand as a thickener, a carbide or diamond wheel grinder would work best (after it quits raining).. Strong and 100% waterproof. To keep bolt threads from sticking to epoxy just warm them up and roll in a piece of bees wax, and a nut or two or three can also be spaced at the desired depth, but dipping the nuts and bolt together into molten beeswax works best. Apparently sheep's wool lanolin can also be used and some claim it prevents crevice corrosion in SS. If done carefully the bolt and nuts will imprint their thread pattern and bolt surface into the set epoxy or styrene resin and can be screwed out. Stanchion bolts cut just short of the decks total thickness can be impregnated directly into the deck with no protrusion visible below deck.. But if you want backing plates the bolts will have to be temporarily caulked or hot glued to keep resin from flowing through and captive within deck core. Note; I just bought an old 1971 TC-41. If that engine you are installing is new, do Not forget to re-torque the head-bolts after about 60 hrs run time, or what ever the mfr recommends. Every bolt on this Perkins 4-108 is just past hand-tight.. Antifreeze in the oil is no fun at all, so I'll be experimenting with Sodium Silicate in the near future.. Looking forward to seeing you two on the water again, and perhaps some day sailing past each other..
Bonjour a vous . L'espace entre l'hélice et la jambe de force doit être 1fois et demi le diamètre de l'arbre (arbre de 50 = 50+25= 75 ) Norme mécanique Marine Marchande et Plaisance . Bonne continuation
I watched the sea trials from Tally Ho, and they discovered a mismatch between the prop and the gearbox. The result is that the engine does not perform well, it did not reach the optimum rpm's. Maybe it is worth to have your setup checked.
as for the engine etc, you could waste time on the minutia - or get in the water. you'll notice all 'the boat building' on the other channels - after - they launch! launching is just a way to figure out what you didn't figure out yet. I've observed that 99% of sail boats and 99.9% of power boats never leave the dock. Only the very few brave souls take to adventure.
We like the trudesign seacocks. They are Lloyd's certified and we used them on our last boat. Very happy with them. Why would you not trust them? They don't rot or seize up... Cheers for watching 🙂
Stuart you are a master of positivity I love your attitude and wish I could be half as chilled as you.
If you look at 'Refit and Sail' episode 15, you will see how both George and I have done our engine beds. Using the angle iron means the bolts can't pull out of the timber bearers. Pretty well bullet proof in a roll-over, clamp the angle to the bearers and adjust the engine angle before cross drilling the bearers. You will need to suspend the engine on a ratchet block to make it easier for yourself. You do need to match the prop to the engine horsepower/engine revs/gearbox ratio.
Two old sayings for you Stew. "near enough is good enough" and "good from far but far from good". Doing a great job, worry ye less.
Our prop shaft snapped a couple of years ago. We found a prop shop who had a good selection of used shafts and propellers. It was a lot cheaper than new to have a used shaft shortened and a new key way and threads cut.
Yep, funny job to do wth engine. I have a gap between rope cutter and strut of 25 mm for a 30hp engine, between 12 and 14 mm are used for the elasticity of engine movement since I have no thrust bearing. But what I definitely would like to recommend is the rope cutter which I needed 3 times for max 16 mm ropes. Unbelievable that the cutter is able to cut ropes of this diameter.
You are doing a fantastic job, I'm following you since the very beginning. All the best furthermore!!!!!👍👍👍👍👍
The engine installation is an exciting step. The propeller thrust causes forward movement of the propeller relative to the strut due to deflection in the rubber engine mounts and possibly some movement within the transmission. I measured at least 7mm between idle and full power on my yanmar 3ym30. It's bad news if your rope cutter hits the back of the strut. Suggest talking to the engine manufacturer about the minimum allowance.
Parsly is good for u !
@@wernerfogel1504so are carrots
I think you should let the shaft protrude 50 mm + from the cutless befaring. You should also take info account the distance from the propellerblade to the hull. This should not be to little, as to avoid redusere turbulence. I think it’s wise to leave cutting the shaft till you’ve decided exactly where the engine will sit (obviously).
Progress no matter how slow is still progress. Go Team Seabird ❤❤❤
It's going to be great to see the prop shaft and engine go in! You two are getting closer and closer! Awesome as always!!!
The engine, heavy as it is, makes up a very small percentage of the displacement. So don't drop it on your toe but don't sweat a little weight change either. As you have pointed out, if the output shaft is going to line up with the prop shaft, the heavy bits will be in a pretty similar place.
When “encouraging” the ends of threaded shafts/ bolts with a precision hammer, I like to thread metal nuts on the end threads to protect them if I strike the end of the threads.
When you remove the nuts, they tend to “rethread” the the shaft/bolt. Thx for bringing us along.😊😊😊
John Ken
Love the shaft Stuart, can't believe your prop came from the bins! Excellent content on this episode, can't wait for the diesel installation.
You love Stuart's shaft?.
The prop was bought second hand.
Waiting to get a solid shaft...
🤣🤣🤣
Cheers for watching 🙂
🤣😂😅
I can really see how great Seabird is going to be when done.. it's amazing what you 2 have accomplished..
Great intro Marina!!
You know your getting bigger as a content creator when you have an intro ❤
🤣🤣🤣
We've had intros before.
Marina made a water colour of our trip on the canals.
Tbh it wasn't planned to be an intro but many liked it so Marina used it again. I think it seems to work.
Hope you enjoyed it.
Cheers for watching 🙂
Just looking back at the start ,I would never have taken on the challenge, didn’t even think it was viable,you have done well, Marina is right to question the prop size and pitch, very important
We have tried looking for definitive answers on propeller sizing, but we are only getting approximate ranges...
The propeller is within that range.
We'll make some more inquiries.
Cheers for watching 🙂
You should have a propeller fitting with your transmission ratio. the clearance between your propeller and your hulll should respect a minimum value to avoid turbulances.
You should wait for the new shaft before fixing the strut. When you will try your shaft you could ad a rubber section around the shaft to be fully center of the stern tube (bicyle handle and tape was ok for me) . if you go with a second hand shaft be sure it s pro inspected to have something straight and perfectly balanced. the stern tube is a replacement or the original ? laminate reinforcement at the base could be an idea.
Thanks for the tips!
Laminate the base of what?
Orginal stern tube.l, new shaft, the propeller I think is in range. 56hp engine, 2.36:1 gear ratio, 22000lbs weight, 33ft lwl.
18x13 propeller...
The only thing left to source is a shaft seal.
But, slowly slowly it's coming together.
Cheers for watching 🙂
That engine base looks so clean! I removed my engine some days ago and now have first time access to my bilge. Identified two pumps and a strange construction containing two switches. Only one pump works. All covered in and between a black swamp :-) Have to clean overhead with a stick as my bilge is very deep. If i fall inside onle my feet will bee seen 🤣 So you are far ahead of my progress stu! Have i mentioned my engine sat on four rusty "things". Have to inspect the next days... So much fun to look your videos. Kind regards Thomas
Engines bilges are never nice place to work.
I hope we can keep ours clean, easier when it is clean...
We think/pray that if we stay on top of the maintenance, our bilge might stay tidy and oil free.
Best laid plans. 🤣🤣🤣
Good luck with your engine.
Cheers for watching 🙂
"On the hole" the toilet looks okay! You guys are great!
Yes, we agree….the boat definitely decides what job comes next. 😆
Our propeller and shaft are both used. Saved a lot of $. Exciting times! ❤️😎🥰
Yup, classic boat life.
"...oh, this needs fixing"
But step by step.
We could find a second-hand shaft.
The only thing needed is a stern tube gland/seal thing...
Thank you for your comments. 🤩
Hope all is well on your boat.
Cheers for watching 🙂
@@SailingSeabird yes, indeed. 😂 Good ol’ stuffing box. Dripless? Or…that other kind, the older, traditional style, which we have.. We’re having trouble pulling the trigger on the clamps. Very important, those clamps. 🤔😆 Another winter in the yard. Our diesel heater goes back with us this weekend. Keeping on. 😆❤️ 🥰🤗😎
Beautiful! So excited for you guys. 🤗. Everything is looking great. 💖⛵🐬🐕
Hope you get the leaks fixed before very long and although it is depressing, at least the rain was nothing like Valencia. I'd guess the greater the distance between the bracket and the prop, the greater the risk of flex in the shaft, so although the load going through the prop isn't going to be massive when everything is running normally, a shorter gap would be better than a long one as long as the prop can clear the bottom of the boat. All the best!
Thanks for the advice.
Etween yourself and the other viewers, we start to formulate a plan 🤣🤣🤣
Cheers for watching 🙂
Nice relaxed episode. Holiday must have done you good. 👍
Rope cutter a must saves you going over the side at 2 in the morning cold water, jelly fish sharks. Plus boat will be moving up and down very dangerous whack on the head or worse get hit by the prop.
That doesn't sound like an ideal situation 😕 🤔
Thankfully, two of our viewers bought us a cutter.
Cheers for watching 🙂
Loving the progress. Great vid thanks guys from us near the Hamble.
Watching the amount of water that came in the open filler hole, I had an idea. For the water filler, inside the hull, have a diverter "Y" that you select one way to fill water tank (drinking water), or switch the other way to capture rain water in a tank for washing.
We have been thinking of a water catchment system.
The y valve idea might work.
Good thinking.
Cheers for watching 🙂
Looking forward to the engine installation!
Plenty of content! When you get on to the rig it is going to be wild!
Best channel on RUclips! Another great video
Keep going. You are doing the best.
Thanks for sharing this video. Progress is progressing. I love watching the process! Love you guys, Katie from Abruzzo
On the way! Go, Go!
Thank you.
Cheers for watching 🙂
Hi Marina,
You are absolutely right, you need a zinc anode around the shaft before the propellor.
What I last episode forgot to mention, is that you should not sand the copper coat before you know when you are going into the water. We were to long on the dry last winter (approx. 8 months) and we really could say that we should have resanded the copper coat. So yes, you should sand the copper coat but not too long before you splash your boat or you can do it again. We will do that at the beginning of next season when we have to get the boat out the water for the antifouling on the propellor.
Luckily, we have only sanded patches of the hull... 🤔
Anodes are a must!
Cheers for watching 🙂
Nice one..really good one..looking forward to this weeks episode already
Thank you.
Lots of messing about this week.
Prepping as per usual 🙄
But we're moving forward.
Cheers for watching 🙂
Nice workmanship always!!
Thank you!
We try and do the best we can.
Cheers for watching 🙂
Keep up the great work u 2 light definately in view with sound of water lapping the hull 🎉
This was a week of more technical tasks but you handled them well.
Technical..?
All we seem to do is sand!
😂🤣😅🤣😂
Cheers for watching 🙂
One consideration is that the prop should be spaced from hull at least 15% of diameter of prop. If you decide on a larger prop later you might nor have enough room . ( 15% clearance stops prop noise).
Also fyi prop shaft should be slightly offset from straight to compensate for the prop walk
Cheers warren
Have you watched the new engine install by "Sailing Magic Carpet"? Of particular interest may be the video "installing a thrust bulkhead - why we need it" from about 5 months ago? they discuss the energy (thrust) and force generated every time the propeller shaft is put in gear and how the force to transfered to the gearbox. It might give you ideas on how you want to proceed.
Great video stu I so wish I could be as chilled as you come across lol 😊
You and me both!
🤣🤣🤣
Cheers for watching 🙂
goo show guys
Glad you enjoy 😉
Cheers for watching 🙂
Absolutely brilliant and keep going 👏🏿👍🏿.
Reading the comments sounds like the rope cutter is a must have....don't cut corners you may regret later. The weather looked terrible at the start of the week, but identified like what Stu said, what jobs the boat needs done....and not what you want done.
Well done you two! Everyday one step closer!! Cheers !
Standard and metric prop shafts have specific threads, per shaft diameter. Tapers, as well. Oh, lap the prop, to the shaft, before installation.
New shaft HIGHLY recommended, as well as shaft coupling.
Best wishes.
Keep going guys ... 5 go sailing, had to haul out there boat to check a P shaft leak.. the seal was with glass and a bump had broke the seal..
When you seal yours fit a sandwich inside to brace it and use a sealant that remains slightly rubbery flexible to avoid that sort of leak developing.
Thanks guys..
I have gone through installing a new engine, shaft and propeller. Here are a couple of comments.
1) As far as the spacing between the propeller and the "P bracket" standard practice is to keep it to 1.5 times the shaft diameter or less. Since you are installing a 30 mm shaft, that means keep the distance to 45 mm or less.
2) Sizing the prop s quite a bit more complex than it might seem at first look. The idea is to size the prop (diameter, pitch and blade type/number) so that the engine can get to just above its rated rpm at full throttle. For example, if your engine has a 3,000 rpm rating at full throttle, you would like the engine to be able to get to say 3,100-3,200 rpm at wide open throttle running on flat water. The prop parameters that matter are: diameter, blade count, disc area ratio (area of blades divided by the area of a circle with the diameter of the prop) and the transmission gear ratio. Pretty much any prop shop can give you a good estimate for a specific prop. It is a good bet that you will need to have a second hand prop repitched. A rule of thumb is that a prop can normally be repitched by +/- 2". There are ways to very accurately calculate the pitch for a specific prop from the details of your hull (waterline length, waterline beam, wetted surface area (including the keel and rudder), depth of the hull exclusive of the keel, waterline area and displacement. You would also need to know the maximum cross sectional area of the hull above the waterline including the cabin house and mast. Finally you need to know the displacement. A naval architect or good prop shop can then calculate the required prop pitch very accurately. There are other less accurate methods that don't need as much calculation, but they often require repitching the prop after a sea trial (more money). Here is a link to a video that discusses prop sizing. ruclips.net/video/eYjmL7fhZEU/видео.html Here is a link to the method I used to calculate power required to move the boat as a function of speed - ruclips.net/video/VxDWt-jFC9g/видео.html
arbitrary is an excellent word for what you saw
Steady as she goes. Thanks for sharing.
Hi Syu, i had a lot of vibrarion problems with my drive and I learnt a bit about shaft drives. With the P bracket, you should fit the prop as close to the bearing as possible. Also if you can afford it fix flexuble coupling between the gaer box and shaft. Good luck, I used Vetus marine, they have recommendations for prop installations.
Hiya,
Thanks for the advice.
We have an R&D flexible coupling.
We installed one on our last boat.
Cheers for watching 🙂
Encourage it with the hammer, lol.
Super cool (in Franglaise 😂) Great work well done “on the smell of an oil rag” 😅👏☝️❤️🇦🇺
'Tab washer'. Keep on keeping on! Best wishes.
Re leaks,, you know for fighter jets, they do a 'leak test' after a long layup, often using a fire engine to spray water under high pressure at the access panels and cockpit etc and yes they sometimes leak more than you'd think! So well done on your 'water shower' test and now you know what's leaking and what's not! You couldn't do that in the hangar.
thanks for the video, best of luck to you both!
Check the space between the hull and the top of the propellor, to avoid cavication.
The gap seems pretty good.
We hope so anyway 🤣🤣🤣
Cheers for watching 🙂
Well done both of you another good video
I don’t know how you do it day after day ❤
Everyone understands arbitrary ... Just googled it to be sure
Perfect choice of words Marina.
Fiberglass repairs, will go bad from the sun if not painted. So maybe cover or paint the repairs.You two have come a long way,from the buying of the boat ! Crack on
Os sigo desde el principio y ya rengo impaciencia de veros cruzando océanos
Excellent, thanks 🎉🎉🎉
The mosquitos love Stu
Yeah, that "fill" job on the plywood looks good. But, I'm worried about the build-up on that engine bed breaking off with the vibration of the engine. I doubt fiberglass lamination would be good enough. What I'd recommend is getting two pieces of "H iron" that would sit on what's there like a saddle, through-bolted on, and provide a channel to hold the buildup pieces, those also through-bolted. That'd be real strong. Even adjustable if you had an engine change down the line. Give it some thought, eh?
Yes you can do it all inside but then you have to take it out and you will find out if all is ok normally no it’s not but you won’t know until it rains
Leak hunting is a fun sport.
I'm sure we'll get most of them sorted.
Cheers for watching 🙂
Great work!
keep going, little jobs take the most time
i have a prooellershaft 30 mm thats even fits your propeller. its free for you
I believe the rule of thumb for the gap between the bracket and the prop boss is; the m 18:12 aximum allowed is no more than 1.5 times the shaft diameter. If you fit a nut which incorporates a sacrificial anode it might be worth fitting a rope cutter between the prop and bracket so make sure there is enough clearance without restricting the flow of water through the bearing.
The criteria which affect prop. selection are as follows. Engine HP, gear reduction ratio, shaft speed, hull design incl. length at waterline, shape and design speed. The water exerts pressure on the surface of the blades, too much can cause cavitation and excess slippage if the surface area is too small. The surface area is affected by the number of blades, the shape of the blades, the disc area ratio, or relationship between surface area and diameter. The pitch is the theoretical distance the prop travels through the water during during one revolution. Multiply this by the shaft speed (RPM) X60 will give you the hull speed in MPH. A certain amount of slippage is to be expected.most props are overpitched to a degree, but too much pitch will prevent the engine reaching maximum revs. A prop which is too big will overload the engine cause black smoke, overheating and rapid wear.
Propeller design is a dark art, even the experts often get it wrong. The prop you found is an equipoise type normally found on high speed craft capable of planeing, it has a higher disc area ratio than normal and would probably cause excessive drag under sail, thereby slowing the boat down.
Prop diameter, engine mount type, and obviously thumb size play major roles.
Looking good.
Hello again. Another good video of your progress. I thought in a previous video you had a new prob shaft? Are you considering if a folding propeller will fit on your boat? Ok, looking forward to next weeks video. Ciao. geo
Looks like she’ll float. Should def address the deck leaks asap. Refer to the early photo’s for encouragement. Must smell better, I hope?
You are getting more Americans done, keep it up, the great work, and have a fantastic weekend
Nice .All good.Enjoyed the Vid
Glad you enjoyed it.
Cheers for watching 🙂
Guys please take professional advice on the prop shaft, it will be the cheaper option in the long run.
We ask the local professionals here all matter of questions.
They are a great resource.
Plus researching what we can.
There are so many companies that will give you a little bit of help and advice.
But we like to do the work ourselves, we need to know how to do the job.
Cheers for watching 🙂
For Stopping Leaks While It's Raining, (which it's doing a fair amount here on Van Isle). I experimented with a method for plugging any size or shape of hole, I use Gorilla polyisocyanate based glue (its the one that looks like liquid honey) I use almost any thing as a thickening agent, like sawdust, silica sand, bicarbonate soda, micro beads, etc... Just start with a dry substance. After mixing the glue and chosen filler to the desired consistency and the thicker the better. Back up say a 2'' hole in deck with a piece of polyethylene sheet or closed cell foam propped in place with a plywood scrap. Just before filling the hole spray or add a few drops of water and mix some more, also if it's not raining, moisten the walls of the hole. This will activate the expansion properties of the glue, filling in any lateral holes or cracks in the main hole. A golf ball size of mix will expand to tennis ball size. After about 3 hrs The final patch will stand proud of the hole or crack and can be sanded flush. In the case of using silica sand as a thickener, a carbide or diamond wheel grinder would work best (after it quits raining).. Strong and 100% waterproof.
To keep bolt threads from sticking to epoxy just warm them up and roll in a piece of bees wax, and a nut or two or three can also be spaced at the desired depth, but dipping the nuts and bolt together into molten beeswax works best. Apparently sheep's wool lanolin can also be used and some claim it prevents crevice corrosion in SS. If done carefully the bolt and nuts will imprint their thread pattern and bolt surface into the set epoxy or styrene resin and can be screwed out. Stanchion bolts cut just short of the decks total thickness can be impregnated directly into the deck with no protrusion visible below deck.. But if you want backing plates the bolts will have to be temporarily caulked or hot glued to keep resin from flowing through and captive within deck core.
Note; I just bought an old 1971 TC-41. If that engine you are installing is new, do Not forget to re-torque the head-bolts after about 60 hrs run time, or what ever the mfr recommends. Every bolt on this Perkins 4-108 is just past hand-tight.. Antifreeze in the oil is no fun at all, so I'll be experimenting with Sodium Silicate in the near future..
Looking forward to seeing you two on the water again, and perhaps some day sailing past each other..
I was out looking at yacht seen stoo sanding the prop shafts hole I’m still waiting for the boat yard to get back to my a but the big yacht
What a coincidence I'm actually eating a hot dog!!
17:25 sometimes it’s $$ well spent
Very true!
Cheers for watching 🙂
She is looking good. GIL.
But she looks wonderful she's almost 100 💯
I see, a feathering propeller is not on the shopping list ~
⛵️ ⛵️ ⛵️ Phil...
You been working on it for 3 years 😅
Bonjour a vous . L'espace entre l'hélice et la jambe de force doit être 1fois et demi le diamètre de l'arbre (arbre de 50 = 50+25= 75 ) Norme mécanique Marine Marchande et Plaisance . Bonne continuation
🥰
18:15 you’re not raising it far enough to make a huge difference
Thanks for the vote of confidence.
Most of the refit is quess work 🤣
Cheers for watching 🙂
Thought wrap anode went there at back
I watched the sea trials from Tally Ho, and they discovered a mismatch between the prop and the gearbox. The result is that the engine does not perform well, it did not reach the optimum rpm's. Maybe it is worth to have your setup checked.
All this talk of "P" sizes this should have been aired after the watershed. 😂😂😂
Why don’t you put up a tarp over the boat ?
Nothing wrong with getting a used prop shaft ... lots of folks do it, and have no problems whatsoever.
We looked, but I couldn't find one long enough. Our prop is second-hand.
Try and stretch the budget a little.
Cheers for watching 🙂
The gap between the boss of the prop and the P bracket should be as small as possible . Those that have a huge gap are not correct .
👍🦘🇦🇺
☔
as for the engine etc, you could waste time on the minutia - or get in the water. you'll notice all 'the boat building' on the other channels - after - they launch! launching is just a way to figure out what you didn't figure out yet. I've observed that 99% of sail boats and 99.9% of power boats never leave the dock. Only the very few brave souls take to adventure.
Totally agree!
Nothing is ever perfect.
Get done and get going.
Cheers for watching 🙂
Guys plastic underwater through hole fittings are very risky...they should be bronze or brass
We like the trudesign seacocks. They are Lloyd's certified and we used them on our last boat.
Very happy with them.
Why would you not trust them?
They don't rot or seize up...
Cheers for watching 🙂