I have seen a fair number of pictures of people stuffing pool noodles into their boats for floatation but not very many people using spray foam, just wondering why? Is it a buoyancy thing, are noodles more buoyant than spray foam? I understand the issues with removing them to dry the boat, but with the boat I am building, the entire front of it will be inaccessible once I skin her so I will not be able to pull out anything.

cheers,
corey

The main issue with the spray foam is that it will take in water over time and you can never get it out. This happens mainly where you cut/sand it flush with he framework prior to sheeting. I've tried it in a few builds over the years and it always turned out bad after a year's running. At the end of the season boat weighs a ton, can get water out, wood starts rotting from the inside. Noodles absorb LESS water it seems, and more importantly, they do not fill the cavities 100% so there is always a bit o breathing room as little as it may be ( if there is a leak that let water in).

Thnkx for the info.

~C~

mephiskapheles6 wrote:

>but with the boat I am building, the entire front of it will be inaccessible
>once I skin her so I will not be able to pull out anything.

If there is any way possible, I would make some way to get at least one hand in
the nose of the boat anytime I needed to.

Since your sponsons couldn't be constructed by building them around structural
high density foam (like Marc does his Warriors) I would just fill the central
rectangular space in the bow with packing noodles (peanuts) or better yet, small
pieces of high density closed cell foam (the stuff pool noodles is made from).
That space looks like it's large enough to provide flotation.

To let the sponsons breath but not have the floatation material enter them, some
nylon or aluminum screen could be placed over the openings before the skin goes on.

Also, those small enclosed spaces at the tip of the bow should have vent holes
provided so they can breathe thru the central bow space where the flotation is.

It only takes a few minutes using a chef's knife and a cutting board to convert
a pool noodle into peanut shaped pieces.

To remove the pieces at the end of season for a total dry out, spraying some
compressed air into the bow space should get most of them out. Sweep 'em up and
bag 'em for next season.

__________________________

IMHO, Marc's warning about spray foam is good advice - never use that stuff if
there is any way around it.

Does this apply to Fibre Glast's #24, #25 mix & pour foam. It says the closed cell content is 90+% & the water absorption is .07 lbs/ sq. ft. of cut surface. Supposed to stand polyester, epoxy or vinyl ester resins.

JA

I'm thinking JA is referring to this product:

www.fibreglast.com/product/2_L...Foam_24_25/Foam

If the expanding foam idea appeals to a builder, then this is definitely one that
deserves consideration just because of the USCG rating. I'm thinking it could be
used to fill sponsons on riggers but that isn't anything I have experience with.

With the generous nose volume in the hydro you are building, I don't think you
need to go the expanding foam route to have effective flotation but I could easily
be wrong.

One of the best features of wooden boat construction is if something does not
turn out to your liking, you can always build another hull and it almost always
takes a lot less time than the first run did (and the results are often better
too).

Building scale boats will never be a process that really goes fast. They require time and detail.Take your time for the best results. A year on the bench isn't out of the question for a scale. If you use the pour in foam be sparing and make site it's fully cured before trimming . I literally mean a few days coz if it continues to expand after you trim it and deck it u could run into problems. The foam can easily bust the seams. The one thing about it, is it adds rigidity to the boat. Make sure you get the right kind if you go that route.