Gorilla glue diy pour foam

[sflinux]

I have been using this technique to make gorilla glue foam:
https://www.youtube.com/watch?v=ggekRdoQJNE
I like that the gorilla glue cures faster and has smaller bubbles.
But sometimes, it expands more than I would like.
I recently came across this instructable, where Andy Callaway mixes gorilla glue with corn starch:
https://www.instructables.com/Gorilla-Glue-Foam/
This gives a rigid product that is fairly easy to spread, and dries with a very rigid surface.
I also experimented with premixing the corn starch with water, or vinegar, but that lead to an inferior product.  I definitely recommend just adding corn starch neat.  I would say the benefit of this technique is it doesn't foam as much as the above (vinegar/baking soda) technique, which could be useful for thin patches (< 1 cm) where you don't want to waste a lot of epoxy & q cell, which can be a little runny.  The jury is out on which is lighter.
I was trying to make a product similar to this foam putty:
https://www.amazon.com/Horizon-Hobby-Woodland-Scenics-WOOST1447/dp/B0006NARV8/ref=asc_df_B0006NARV8/
Inspired by this repair video:
https://www.youtube.com/watch?v=lsQp-Z2mKMY

[tarquin]

I have seen various techniques but never the corn starch! If you do add water you only need 1 or 2 drops.
 A friend of mine is a boat builder and he was talking about a rudder somebody built. They had glued slabs of wood together with PU glue, same as gorilla glue. Then shaped it.They were going to glass it and he said that's a really bad idea. He was taught epoxy dosnt like to stick to PU glue. I told him plenty of people do it on surfboards.
 Has anybody noticed epoxy not stick to a PU glue line?

[TallDude]

I've had the epoxy separate from EPS foam, but it won't come off the PU glue. Here's a board I pieced together with Gorilla Glue and scrap foam. Even spliced the stringer together with GG. The wood tail block is set with GG. The fin box is set with GG. It's been at least 5 years and no delamination anywhere on the board.

[Beasho]

I will call this a "How to Faster Cure Gorilla Glue"

I saw that original video and said Phoohooheee.  Too Complicated.

So I just add a few sprits of Water to the Gorilla glue and whip it until it turns white.  This cure fast, fills voids, has a solid internal consistency and sticks to everything.  Density is ~ 4 lbs / ft^3

I have repaired multiple tuttle box failures, broken boards . . . using this system and have found that Gorilla glue, unlike epoxy, actually does stick to everything such as divinycell.

I have laminated over this and NOT had failures put to pretty extreme tests. 

https://www.youtube.com/watch?v=UgZ3A3igBbY

[Beasho]

Here is a link to one of my box repairs showing the Gorilla Glue Fill layer:

https://www.standupzone.com/forum/index.php/topic,35287.msg406243.html#msg406243

[tarquin]

I did argue a bit with him. Obviously its fine. Just weird they would teach them that. Maybe he just got it wrong. Did a few google searches and lots of evidence to say epoxy bonds well to PU.
 I bought some additive for epoxy that makes it foam ages ago. Used it once to glue wood to a foam core. It worked. No idea if it was better.

[Dontsink]

So this stuff would be good to glue in a foilbox?.
It is a big rectangle of high densityPVC foam,will nest in EPS board.
I want something that will stick,fill voids without soaking into the EPS and not expand with too much force.
I will clamp the foil box to the board but it could still deform or lean...
Starched or neat?

[TallDude]

Yes. Just a moist paper towel wiped on the surfaces before you apply the glue. It does expand a little. The wetter you get it, the more it expands. You won't get the exotherm as you do setting fin boxes with epoxy and larger gaps. When you have to big of a gap between the foam and fin box, the addition volume of epoxy will get hot enough to melt the foam away from the fin box or leash pug. GG won't do that. It will actually fill the voids with a foam stronger than the high density foam you're setting it in.

[Beasho]

Paper towel and regular gold Gorilla glue will NOT fill voids correctly.  You need to whip it up.  See this video again.

Gorilla glue that hasn't been cured with moisture Inside and Out will create its own bubble inside the matrix.  If you test it in a dixie cup and then CUT the foam you will see what I am talking about.

https://www.youtube.com/watch?v=UgZ3A3igBbY

[Beasho]

Here is how it all went together using Purple XPS foam, in EPS with a Tuttle Box, Gorilla glue WHIPPED White.

Layered with 2 X 6 oz of Fiberglass and then 2 X 6 oz of Carbon TOP and Bottom.

This board was built with Dual Tracks sitting on top of beer cooler foam.  The boxes melted down in 5 sessions. 

This Tuttle Re-Installation has lasted 2 1/2 years. 

[Vancouver_foiler]

I've done the tour starting with Gorilla glue and them moving to all types and brands of pour foam. I'm back to Gorilla Glue-when whipped up it is a consistent foam structure(as shown above) and sticks to most anything.

Question-does it absorb water?

[Dontsink]

Ok,thx guys.
I have ordered some Gorilla Glue.

[Bean]

Question-does it absorb water?

Yes, but so does pour-foam.  Treat it just like bare EPS and you're good.

[Dontsink]

Question-does it absorb water?

Yes, but so does pour-foam.  Treat it just like bare EPS and you're good.

And i was sure  PVC foams were mostly waterproof,being closed cell.At least a lot more water resistant than EPS...

So they are not?, i am right now using Foam-it 5 pour foam to fill some cavities,it will be glassed over but i thought the foam would be a water barrier too.

[PonoBill]

PVC is a closed-cell foam, standard EPS is not, XPS is somewhere in between. Two-part pour foam is a closed-cell and the better versions have strength somewhere between XPS and PVC. Gorilla glue that's been whipped with water is stronger than two-part foam and sticks better. Two-part foam eventually breaks down with continued pressure and eventually loses its water resistance even before it gets weak. I've used gallons of two-part to make body-formed seats for race cars. Mix well, pour into plastic bags, tape it to the seat base, and sit down. Don't pour in too much or you'll have it in your hair (not that I'd know).

I have an old hand mixer with a modified single beater for mixing epoxies, foams, and gorilla glue. I clean the beater by holding it in an empty bucket and switching it to high, then wipe off the tiny residual mess with a rag. Power mixing changes the entire game. Hand-mixed gorilla glue has voids with dense areas of poorly cured glue. Power mixed it's as consistent as commercial PVC. I haven't tried cornmeal though I've tried micro balloons to try to get a lighter filler. That works though it's hard to get enough in the mix to make it worth the effort when the glue is doing its best to turn to foam before you can finish.