2 part foam installation method...

[noworries79]

Hi everyone,
I had a question about the 2 part foam...should I place the foam before adding the deck? I have heard some on this site actually cut the foam after pouring to fit the deck in, but I am not too sure. I have noticed that there were plugs in my previous deck that may have been the injection sites for the foam at the plant. I am a little paranoid about the foam getting wet again (removed about 100 lbs. of wet foam before). Is it safe to cut the foam while keeping the water-proof properties? Just trying to think ahead. Thanks in advance.

 

[Bondo]

Re: 2 part foam installation method...

I am a little paranoid about the foam getting wet again (removed about 100 lbs. of wet foam before).

Ayuh,... Regardless of the foam used, or how it's applied, or whether you use it at All,.....

DRAINAGE should be your 1st,+ foremost thought.....

 

[jspano]

Re: 2 part foam installation method...

i don't want to hijack this thread.... but,
i can't find extruded foam here in fla. noodles(pool) seam expensive.
the 2 part foam is that extruded or expanded?
can i build forms to pour the foam and then cut and fit it into the boat?

joe

 

[Bondo]

Re: 2 part foam installation method...

i can't find extruded foam here in fla.

Ayuh,... I know the home building business is alittle Slow the Florida,...
But,...
I find it hard to believe all the Building Supply stores have gone belly up too....
Even the Boxstores around here sell extruded sheets....

 

[mikezohsix]

Re: 2 part foam installation method...

as said above by the transplanted Mainer,

drainage is number one.

All the damage to my boat can be attributed to poor drainage past the OEM poured in place foam. Even though they had "dams" to prevent the foam from going certain places, it still prevented good water flow, and the cleaning action that you need to keep the bottom of the boat from silting up over time.

I will NEVER do poured foam in one of my boats - ever.

mk

 

[noworries79]

Re: 2 part foam installation method...

Ayuh,... Regardless of the foam used, or how it's applied, or whether you use it at All,.....

DRAINAGE should be your 1st,+ foremost thought.....

I am leaving the space between stringers empty and filling the outer portions with foam. What do you think about cutting a PVC, leaving 65 degrees to fit outside the 2 stringers? I hope that this will keep the foam slightly elevated and away from any water.

 

[BobsGlasstream]

Re: 2 part foam installation method...

The two part foam is mixed then poured into the area you want and it raises.
As for pouring it and then cutting it to fit. The closed cell foam used today does not absorb as much as the older foams however if you cut it you will open some of the cells that will absorb water but only to a point. If you cut the skin that forms on the foam you will need to seal it with something like paint, resin or something similar to prevent it from absorbing water.
Bob

 

[jspano]

Re: 2 part foam installation method...

Ayuh,... I know the home building business is alittle Slow the Florida,...
But,...
I find it hard to believe all the Building Supply stores have gone belly up too....
Even the Boxstores around here sell extruded sheets....

the key there is the Boxstores around here sell extruded sheets....

the only thing i can think is it might be used in the building industry for basements, and we don't have basements here, that's what i was told.
every store i go to knows what i'm talking about but it is no longer in their stocking assortment.

 

[DukesFin]

Re: 2 part foam installation method...

Yeah... I seriously doubt that the big box stores down in Florida sell the 2" thick sheets of extruded foam. They do up here in Atlanta though.

Can your local "big box" store order a sheet or two for you though? Seems like if stores up here have them, your store would be happy to get you a sheet or two if you pre-pay for them...

Just an idea.

 

[DerDer]

Re: 2 part foam installation method...

I am having the same problem in San Diego. No one carries extruded poly sheets. Home Depot can't even order it. Lowe's can, but at $69 per 2" sheet.

Think I am going to use pour-in foam from US composites. I was thinking about wrapping the interior of the hull in plastic wrap, pour in the foam, then pull out and remove the plastic wrap. That way the foam blocks won't be stuck to the hull to help with drainage.

Does that sound feasible?

 

[Bondo]

Re: 2 part foam installation method...

Ayuh,... Better 'n Nothin',... I'd leave the plastic in place....

Limber holes the the stringers, leading to the bilge,..??

1 guy left ropes laying in the hull,+ pulled 'em out after the foam set up, leaving channels...

 

[jspano]

Re: 2 part foam installation method...

my question is the 2 part foam closed cell, my old foam was wet and i'm not sure if the foam was to blame or lack of drainage from the tight seal the pour made?
also rcfoam.com sells blue foam

 

[noworries79]

Re: 2 part foam installation method...

1 guy left ropes laying in the hull,+ pulled 'em out after the foam set up, leaving channels...

This is what I hope to acheive with the PVC pieces I cut running the length of the stringers. The plastic sounds like a great idea!

 

[PiratePast40]

Re: 2 part foam installation method...

On mine, I secured some deck sections but left others open to insure there was good expansion. The large open spaces at the bow were the hardest. I used cardboard wrapped in garbage bags to form dams for the foam to push up against. After I was sure ther was enough volume in the voids, went ahead and secured the adjacent deck sections. I used a 2" hole saw and saved the plugs. Having the hull tilted bow down is an excellent way to get the foam to flow forward and expand back toward your pour hole. Once you've filled up one chamber and it's coming back up the hole, you can move to the next one back.

If you run out of foam, it's only a day or two wait to get more. DO NOT try to finish up with the insulation type foam in a can.

Just make sure you have enough large plastic cups premarked for measuring and pouring. You'll go through quite a few stir sticks and gloves as well. Best thing is to read up and experiment with a couple batches first.

It's not as hard as it sounds, just make sure you have the temp up to get maximum expansion. The temp was a little low on the hull when I did mine so I used space heaters and a blow dryer can help bring temps up over 80.

After everything was done, I used a spade bit with the point filed off to clean up the holes and then glued the plugs back in. It'll take resin and filler and then some sanding to level things out. After the deck is done, you can continue with the mat or cloth treatment you were planning on in the first place.

 

[jspano]

Re: 2 part foam installation method...

PiratePast40

how big was your boat and how much foam did it take?
where did you buy it from

thanks

 

[PiratePast40]

Re: 2 part foam installation method...

Joe,
My boat is an 18' Fiberform runabout with a closed bow. Bought my foam from jgreer.com (Aero Marine) in San Diego. I suppose any of the suppliers are OK, these guys just happened to be on the west coast so the shipping was reasonable for me. Their web site is also pretty helpful. I used 2 - 2 gallon kits plus an additional 2 quart kit. Each kit was 1 gallon of each part. I was using 2# foam so each gallon kit (2 gallons total) is supposed to yield 8 cubic feet.

The temp during the cure makes a difference. You'll get the best expansion at higher temperature. I don't remember the exact temp but I believe it's in the mid 70's for best results. The company above has pretty good instructions on their web site as well as with the kit.

I practiced using a couple of 4 oz pours into a bucket lined with a trash bag to get an idea how it works. Really pretty cool stuff.

Here's a link to someone who also poured after the deck was in: http://forums.iboats.com/showthread.php?t=188444
There are some other pretty good ones as well.

I didn't bed the deck to the hull or do any of the tabbing until after the foam was poured because I was afraid of over expansion hurting something. Afterwords, I realized that if you do it right, over expansion shouldn't be an issue if you leave relief holes and watch what you're doing.

For mixing cups, I went down to a restaurant supply store and bought a sleeve of 24 oz plastic cups. You'll go through a few of those since you won't want to reuse those right away. The measuring containers can of course be reused right away - just remember which one is "part A" and which is "part B". I marked mine at 4 ounces so it was consistent with each pour and then increased the amount after I got more comfortable with the process.

Again, your best bet is to mess with it a little first to get a feel for the time you have to mix and pour. You'll also learn really quick about having plenty of gloves and paper towels ready. The stuff is a real mess while curing but simple to clean off the plywood, plastic cups, and tools after it's hardened.

Just be warned, it won't come out of your clothes and is a bear to get off your hands. Accidentally kneeling in a puddle of the wet stuff will show how good an adhesive it is, believe me, I know :redface:

 

[noworries79]

Re: 2 part foam installation method...

This may sound strange, but I am seriously considering using "noodles" for floatation. I have read that the 4" dia. noodles can float 200 lbs. Since I am only putting foam into 2 cavities this may be the way to go for me with a 16 foot boat. I am on the hunt for noodles at the dollar stores!

 

[jspano]

Re: 2 part foam installation method...

don't want to hijack this thread.... but,
i can't find extruded foam here in fla. noodles(pool) seam expensive.
the 2 part foam is that extruded or expanded?
can i build forms to pour the foam and then cut and fit it into the boat?

i to am looking at noodles. walmart has them for 2.00 apiece near me and that's alot cheaper than i found on line. seems it would be easier to install and better for drainage

 

[ezmobee]

Re: 2 part foam installation method...

This may sound strange, but I am seriously considering using "noodles" for floatation. I have read that the 4" dia. noodles can float 200 lbs.

Hey no joke, pretty sure I'm going this route as well.