Foam Under The Deck Question

[Dredgeking]

The foam under the port side of the deck has fallen down. it's a clean separation. looks like the foam lost it's grip. do i need to glue it back up there? is the a BIG purpose to it? i'd rather pull it out and not have to deal with it.

thanks

[oldLenny]

I would replace the whole shooting match. It does have a purpose. It is there to keep the deck "true" with heavy loads, eg: people, and is to make up for the lack of very heavy/expensive THICK mat and roven lay-ups....(that are not there) It will compromise the rigidity of the area and is an early sign of things to come. Time to recore. If it "fell" done then the open cell foam is no longer bonding and with the resin content in the cellular structure it will no longer accept any resin, or at least to any extent to become what it is supposed to be.
In saying all that, you mean the foam (1/4-1/2") that is on the underside of the deck?...right?

[Formula Jr]

Dredgeking, where exactly is this foam?
From your description it doesn't sound like the
encapsulated deck core, which is what Lenny is talking about. Pics?

<small>[ March 13, 2003, 07:48 PM: Message edited by: Formula Jr ]</small>

[Dredgeking]

jr., pics. yes. i forget the digital age. uno momento .

[Dredgeking]

here it is http://www.donzi.net/photos/dk20.jpg

[Dredgeking]

the deck actually looks great. i just have this foam throughout most of the boat. seems to be very old school.

[Formula Jr]

Thats just added floatation foam. I kinda like floatation so I'd just use an adhesive and stick it back up there.

[Dredgeking]

thanks for the info guys. gotta love this board.

[Formula Jr]

5200 would be a bit of overkill MP.
Actually, during that vintage, i think the CG changed some of the rules regarding how high a boat has to stay afloat while swamped. That might be why they added it all over the place. Anyy old latex/silicone caulk/adhesive should work. I'd put it back, since it does have sound deadening value.

[Rootsy]

my 97 16 doesn't have any of that sprayed up there... BUT i do have the hull forward of the tub filled... fore of the kick panels on both sides... two big blocks.. but the deck is as it came out of the mold...

[Dredgeking]

the boat has a 76 HIN and says 77 on the title. so this may make sense.

[Formula Jr]

I'm pulling this info out of a hat - vague memory, but up until '76 a swamped 16 Donzi was heading for the bottom. Positive floation was required somewhere around this time by the certification board of the CG. By '85, not only did the boat have to maintain positive floatation, but it had to support someone of average weight out of the water. '71 seems alittle early for that certification, but I'm wrong about alot things.

[riverrat]

go to a a/c supply house & buy a can or two of spray adesive. it's made for insulation & may work fine. or you could go to home depot & buy a can of spray on insulation just like what's there & do it that way.

<small>[ March 13, 2003, 09:50 PM: Message edited by: riverrat ]</small>

[Formula Jr]

There's two kinds of the spray foam out these days. One is "Great Stuff" and the other is a latex based type. Don't use the Latex based foam. It has no holding power. "Great Stuff expands like cazy, so be econonical in your application.

post 1654 wink

[ToonaFish]

Um, duct tape.

[MOP]

Toona bailing wire is far more Shiek!

[Dredgeking]

hey, that's a better idea guys. re-foaming it with great stuff would be much easier than trying to get the old foam to re-adhere to the deck. cool. nice brainstorming. :) thanks. i love great stuff.

[krakmeup]

My 1976 Classic has this foam all around under the decks and towards the stringers - in fact, it has cracked with age and freezing to where I first thought the boat had serious issues, but then I realized it was just this sprayed-in stuff. I agree with Rat - try the 3M spray adhesive, available at the local auto store or walmart for $10-20 per BIG can - it works great on fabrics, so I'm not sure it will work for this. I always have a can of that stuff on the shelf for quick repairs.

Good luck!

[riverrat]

Toona, there you go with the duct tape thing eek! you bad girl.. :p

the rat

[Forrest]

Mid- to late-seventies Donzis had the foam added to comply with a new (at the time) USCG regulation. My '77 x-18 has the stuff. The foam makes it a pain to gain access to cable routing or up under the bow. Plus they put it in the engine compartment between the stringers and the bulkhead and just painted or gelcoated over the stuff. After awhile the foam in the engine compartment gets all beat up and ugly. In the case of GEOO's X-18 with foam, it got water logged and added many pounds to the boat. Also the stuff tends to break off in little pieces and gets caught in the drain-plug hole. Though I haven't completly done so yet with my X-18, I plan to do as GEOO did, and that is to get rid of all of that crap. Right now, I have partally removed it from under the deck and have totally removed it from the engine compartment. With the foam gone, your Donzi will not sink any faster than an older model without the stinkin' foam. :D

---------------
Forrest - Foamless in Tallahassee

<small>[ March 14, 2003, 11:14 AM: Message edited by: Forrest ]</small>

[CDMA]

Foam is such a mess...but the non sinking aspect is a real nice thing...just piece of mind..

I have been thinking of a couple of the air bladder flotation "bags" under each side of the cockpit..any one have any experience with this..

Chris

So comfy knowing my Whaler won't sink...need the same with the Donzi...

[riverrat]

you know Forrest has a good point. that stuff was not closed cell & it does take on water, making the boat weight a ton. they used this stuff in Boston Whalers & Mckee Crafts and they are heavy as can be after many years in service. not much you can do at this point without a major re-do of the boat. so if it bothers you I'd go the spray on
stuff. but it is expanable & very sickey.