Foam Replacement

[LDUBS]

There was no floatation foam between the stringers. Unfortunately, the stringers (~6” x 10” x 117”) are filled with foam. Maybe I can dissolve it with acetone.

Do you think the pour foam, especially in the stringers, is providing some added structural support? Might lean me towards putting pour foam back in. But I admit I'm shooting from the hip here.

 

[Still Afloat]

Do you think the pour foam, especially in the stringers, is providing some added structural support? Might lean me towards putting pour foam back in. But I admit I'm shooting from the hip here.

I don’t think so. The stringers appear to be 1/8” thick and the hull is 3/16” thick. I can’t see the foam adding any significant structure.

That deck is a heavy beast. Lifted one end at a time while the father in law placed 2x4s across the gunnels. He’s 96 and an old boat guy. He enjoyed helping out. Once the deck was the above the gunnels I pulled the boat outside and lifted it off with the tractor forks.

Need to think about what material to use for the new deck. Will make a few calls tomorrow.

 

[David Atkins]

My thought was if the foam board was cut somewhat close to the hull, a quick squirt along the edge to hold the foam board in place....if that is even needed ?
When I look at my 1992 Sylvan, actually their is not much foam in it ! Small nooks and crannies have been filled and much of the under the floor area is foam, but no where near what I expected to be there. Lucky for me all is dry as it has been a garage Queen its whole life.

I agree

 

[David Atkins]

I had the same thing happen, went to set up an electrical system and discovered the foam was saturated and starting to rot the deck. Pulled it all(what a pain) and replaced it with blueboard. Left lots of drain channels and room for circulation. The challenge seems to be in getting enough material for buoyancy.

The fact of the deck(specifically the screws attaching the deck to the hull) would be supporting the wjhole boat also occurred to me. I suppose there are probably around 60 screws on my boat, all told, attaching decking, and the boat is 600 pounds with gear, that's 10 pounds per screw. It doesn't seem unreasonable if the attachments are sound. This all conjecture, though, and to me the more concerning thing is getting enough square footage of bluboard in there.

The last boat I pulled down (Completely) to rebuild have over 300 pounds of water within the foam, I was astounded by how much water was in that Tracker 16 footer and it still floated? Well I went with the blue board replacing all foam and you are correct getting the old out is a pain!

 

[Still Afloat]

I think I’ll just make a mess trying to remove foam from the stringers. There is really no access and I don’t want to cut or modify the stringers. Fingers crossed that it’s drier because it’s enclosed.

 

[David Atkins]

I think I’ll just make a mess trying to remove foam from the stringers. There is really no access and I don’t want to cut or modify the stringers. Fingers crossed that it’s drier because it’s enclosed.

That's a very tough job working with the stringers and getting out the old foam, if it's not water logged (DRY) then I would forgo the pain and suffering (LOL) but it has been done many times before, you have just got to figure out the best method.. Good luck!

 

[LDUBS]

I don’t think so. The stringers appear to be 1/8” thick and the hull is 3/16” thick. I can’t see the foam adding any significant structure.

That deck is a heavy beast. Lifted one end at a time while the father in law placed 2x4s across the gunnels. He’s 96 and an old boat guy. He enjoyed helping out. Once the deck was the above the gunnels I pulled the boat outside and lifted it off with the tractor forks.

Need to think about what material to use for the new deck. Will make a few calls tomorrow.

Those North River boats are built like tanks.

 

[Still Afloat]

So I’m probably going with 3/4” marine ply for the deck. Not that I’m fond of wood decks but, plywood floats and aluminum doesn’t. If this boat had more flotation I’d go with an aluminum deck. If my estimate is correct I’d need to add about 190 pounds of floatation to use aluminum and have the same bouyancy as it would have with a plywood deck. (54 sq ft ~ 95 pounds of bouyancy from the ply vs 95 pounds of aluminum weight) Actually, it would be less since that does not include the weight of the vinyl flooring.

 

[Still Afloat]

That's a very tough job working with the stringers and getting out the old foam, if it's not water logged (DRY) then I would forgo the pain and suffering (LOL) but it has been done many times before, you have just got to figure out the best method.. Good luck!

Think I’ll skip the flotation removal from the stringers. The stringers are fully welded and that should help keep the foam drier. At least that’s what I’m telling myself.

 

[David Atkins]

So I’m probably going with 3/4” marine ply for the deck. Not that I’m fond of wood decks but, plywood floats and aluminum doesn’t. If this boat had more flotation I’d go with an aluminum deck. If my estimate is correct I’d need to add about 190 pounds of floatation to use aluminum and have the same bouyancy as it would have with a plywood deck. (54 sq ft ~ 95 pounds of bouyancy from the ply vs 95 pounds of aluminum weight) Actually, it would be less since that does not include the weight of the vinyl flooring.

So I think your adding plywood will be just fine, I've used it many times in the past; makes the plywood almost water proof if done correctly. I also epoxy coat my plywood on all sides with good quality epoxy. I'll add a site to view, these are the guys who taught me how to do epoxy coatings, they do this everyday at work, check it out at

 

[Still Afloat]

So I think your adding plywood will be just fine, I've used it many times in the past; makes the plywood almost water proof if done correctly. I also epoxy coat my plywood on all sides with good quality epoxy. I'll add a site to view, these are the guys who taught me how to do epoxy coatings, they do this everyday at work, check it out at

Thanks for the link. I got about 3/4 of the way through the video before everyone starting getting up. Will watch it again later.

Any idea of the coverage? I’ve got about 54 sq ft on each side.

 

[Still Afloat]

Found some coverage info on the West Systems site. It looks like a couple of quarts should do it.

 

[David Atkins]

Found some coverage info on the West Systems site. It looks like a couple of quarts should do it.

View attachment 120905

That's about all I ever bought for a single boat!

 

[Still Afloat]

That's about all I ever bought for a single boat!

The price for one gallon is the same as two quarts. Will just get a gallon of 105 and the 206 hardener. I’d rather have more than needed than pay as much for less.

This stuff seems to have a decent shelf life. I’ve been working off a quart of 105 for the past 20 years and it still sets up fine. Will pass the old stuff along to someone.

 

[LaqueRatt]

Am I the only one here who doesn't worry about their boat sinking? Seems pretty damned unlikely to me.

 

[Still Afloat]

I had a boat get swamped last summer. Big lake and a freak wind storm that didn’t even show up on the weather. So yes, I’d rather not sink a boat that I’ve got over $30k in. Not to mention that my fishing buddy is 96 going on 97 years old.

Also, the bigger lakes around here are typically a few hundred feet deep. Lake Pend O’Reille is 1100 feet deep. Recovery would be expensive.

 

[Lost But Happy]

Rogue waves are a b****

 

[LDUBS]

Am I the only one here who doesn't worry about their boat sinking? Seems pretty damned unlikely to me.

I really don't worry about it. There are other potentially catastrophic accidents that are more likely. I still practice good loss control. If the worst happens I like the idea my swamped boat will stay at the surface. Keep in mind that like a lot of other safety items, it is a legal mandate. Purposely removing floatation could even invalidate your boat insurance policy (both for loss of the boat and 3rd party liability coverages).

 

[TriBull]

I don’t worry about it, because I do have flotation foam!

 

[Still Afloat]

I really don't worry about it. There are other potentially catastrophic accidents that are more likely. I still practice good loss control. If the worst happens I like the idea my swamped boat will stay at the surface. Keep in mind that like a lot of other safety items, it is a legal mandate. Purposely removing floatation could even invalidate your boat insurance policy (both for loss of the boat and 3rd party liability coverages