16 foot tri-hull restore advice (Foam in the hull)?

[I'D RATHER B FISHN]

Not sure of the make, but it looks like a McKee Craft. I just cut the floor out and the foam underneath was saturated. I removed it all. I'm looking for advice on whether or not it is ok to not put any foam back in the hull before re-decking. My father in law says he would not put any back in, but I'm concerned about buoyancy.

If foam is the way to go, what is the best foam that is impervious to water? Is there any other alternative material to use instead of foam?

Thanks,
IRBF

 

[I'D RATHER B FISHN]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

PS. It's a single wall tri-hull.

IRBF

 

[kfa4303]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

Hi I'D. It's not uncommon to find water logged foam. The trick is making sure you remove it all. You'll have to rip out and replace the floor to get to it all. You should definitely replace foam. I'm not entirely sure of you model, but some boats actually use the foam as part of the structural component of the hull as well as flotation. If that is the case with your boat, you'll need to get a special two part expanding foam. I'm not that familiar with it, but others will chime in and let you know more. If the foam is non-structural you should be able to get away with using waterproof, closed cell foam such as the pink or blue construction foam panels available at the big box stores. You can cut to shape with simple and tools, then install your new floor over it. When you do remove your floor and stringers try to keep them as intact as possible so you can use them as templates. You'll then want to use high quality, 1/2" exterior grade, or marine plywood for the new floor and seal it on all sides with either fiberglass and wax-free polyester resin, or epoxy, then paint. Once sealed you can then tab it into the sides of the hull to form a watertight seal and for structural support.

 

[Home Cookin']

Re: 16 foot tri-hull restore advice (Foam in the hull)?

If not needed for structure, swimming pool float tubes work, too. But a McKee is a whaler clone, so you want it for structure IMO.

 

[I'D RATHER B FISHN]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

So there's a difference between structural vs. non-structural foam? I'm not 100% sure if the foam I ripped out is structural or not. I will tell you it was saturated with water, but it was in tact. I had to chip it out with a paint scraper. It would break apart in large chunks. It was a yellow/orange colored foam.

Thanks for the replies KFA & Home Cookin'.

 

[I'D RATHER B FISHN]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

Also the hull foam level was all the way up to the bottom of the deck.

 

[Bondo]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

but I'm concerned about buoyancy.
Also the hull foam level was all the way up to the bottom of the deck.

Ayuh,.... Foam only adds buoyancy, After the boat is swamped/ sinkin'....

post a picture of yer boat, so's We all can see what yer talkin' 'bout...

 

[JDA1975]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

As far as buoyancy goes, it isn't needed, consider it a life jacket for your boat, if you have a hull breach it could keep your vessel from sinking before you can be rescued or limp back to the dock. The foam however serves another purpose in these smaller boats, it is structural in nature and keeps your hull from cracking, it also gives your deck more firmness...1/2 plywood doesn't span the distance between stringers alone without something to firm it up, you will have a very soft deck without it. If you do your rebuild properly, it should stay dry for many years, and not be an issue, so replacement is strongly advised.

 

[boat_beginner]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

would it be advised to put foam in a boat that did not have it when taken apart?

 

[I'D RATHER B FISHN]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

View attachment 128086View attachment 128087


Here are two pics. One of the boat & one of the foam before I pulled it all out.

 

[Bondo]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

Ayuh,... That hull relies on the foam for structure.....

That's in pretty sad shape....

 

[I'D RATHER B FISHN]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

Hopefully she won't be when I'm finished with her. Wasn't a bad deal, I picked up the boat and trailer for $200.00. I think a little TLC will get her sea worthy again.

In the pics above it looks like when the boat was built the foam was injected after the floor was put down. How can I accomplish the same process? Thanks for the input. How can I accomplish the same process, if I use two-part expanding urethane foam or would I have to use some other type foam?

Thanks for the input.

 

[glnbnz]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

Hi I'D rather be Fishin...this link will get you some great details about your rebuild...

http://forums.iboats.com/showthread.php?t=510077

Friscoboater did an AWESOME job on this rebuild and took lots of pic and explanatory video...so much to process

Good luck on your rebuild and keep us posted...

 

[I'D RATHER B FISHN]

Re: 16 foot tri-hull restore advice (Foam in the hull)?

Will do Glenn and thanks for the info to you and everyone else.

IRBF