XPS blank and FCS fin plug installation-MELTDOWN

Hi,

 Sometimes my XPS blank is melting down when installing FCS fin plugs even with slow hardener (epoxy)

Does someone has this same problem? Any tips to avoid meltdown?

Thanks,

P

 

Pinguino,

I did a fcs repair on one and am always concerned with melt throughs with epoxy and styrofoam.  I poured one half at a time and covered the repair with wax paper and an ice bag. I think I picked that tip up from Herb S. Having a very close tolerance hole helps.  Thousands of styro boards are boxed, plugged, etc so it’s very doable. For my own boards I do glass ons with eps and avoid the whole issue(and prefer polyU with epoxy).  I like glass on better anyway. Mike

There are casting epoxies on the market (almost no exotherm).

I do normal FCS installs with a casting resin, works perfect.

Had the exotherm on a XPS board recently. I noticed the resin I have is getting really hot when it cures. It’s old and I only have a small amount left. I have since gone to 2 pours for boxes on XPS, but once the resin I have is gone I’ll try doing it in one pour again. All these issues with post lam boxes makes it worth looking at the boxes that you install before the lam. I really like the probox with all the adjustments though.

Don’t use the plugs, the boxes don’t have thos problem and a vastly superior too.

 

Greg is is normal for old epoxy to get hot or cure faster? Mine is not RR or FH and it’s at least 2 years old maybe older.

It shouldn’t change.  I know that polyester does that but the styrene evaporates out of it which causes the change.  Epoxy doesn’t have solvents.

Thanks Greg. I don’t know what’s up, but the last several times I’ve used it I’ve had the part left in the cup smoking, and I mix with a scale, but they were small batches. I did have it get too hot when I installed boxes in a XPS board. I’m down to the last 10 or so ounces, so it’s almost gone. I really liked it though, no blush and it would sand so nice.

Good call Greg.

Set the plugs/boxes/etc first in a sized block of poly or d-cell foam using poly resin.  Route the board to fit the blocks and glue in with pour foam or gorilla glue (use clamps).  No heat, strong install, obviously not done post lam.

Shark,  are you mixing or pouring into buckets or containers that have residue or leftovers from past use?  A bad habit of mine, as long as it is clean I will reuse.  Swear that it has sped up both poly and epoxy batches before.  Worst thing is I continue same thing to this day.  Cannot handle the waste otherwise.

I usually use a clean cup for the resin every time I make a mix. I use another cup to measure out a small bit of hardener then I pour the rest back into the larger container several times before getting out a new one. The resin was in a 5 gallon container, but I pour out smaller amounts into other conatiners to make it easier to pour into cups. The hardener came in a 2 gallon or so container. It’s a 5-2 by weight mix.

In the last several months, when I make small mixes like 2 or 3 oz for boxes or ding repair, I end up with a smoking hot cup if I don’t use it fast enough. If I can get it out of the cup and not too thick, it’s OK.

 

It might depend on what you are thickening the epoxy with (assuming you are using a thickening agent). All epoxies I have ever used cure much faster with colloidal silica added. For some reason glass bubbles have less of an effect.

I do it like Rooster

Being a cheap DIYer for a few years, Ive used microballoons in the mix to reduce the amount of resin used, to reduce the exotherm, and because the function of the pour was to position the plug and the depth of the pour would create stability beyond resin density.

Rooster Mike, you like glass ons better for weight? For me, boxes are the only way to go. For some reason sanding fins drives me batsh$%. If I don’t have to sand one more glass on fin in my life I’ll die a happy man. I make my buddies do their own sanding on the boards I make them. Everything else is cake but glass ons…fugeddabout it.