Official "Problems" Thread - For Those Times

a.badner · Post by **a.badner** » Mon Jan 17, 2011 4:13 pm

OH MY GOD MAN.
DONT IGNORE THIS, THIS IS JUST PURE SAFETY!

( im probably over reacting right now but still scared me. )

DONT EVER EVER EVER... EVER! MIX 1/4TH A GALLON AND 1/16TH OF HARDENER ALL AT ONCE... EVER!

WHILE LAYING UP MY FIRST BASES, my tub of epoxy started to smoke and got extremely warm.

so i quickly open up the garage door and take out the first bases and throw into the snow. so i go back into my garage to abort the layup. while turning off the lights i noticed its way too bright out side. i look back at the tub and the base and they are on fire. ya. on fire

scary scary scary shit

super scared to ever mix epoxy again.

twizzstyle · Post by **twizzstyle** » Mon Jan 17, 2011 8:08 pm

HAHAHAHAHAH duh! I've had plenty of epoxy catch on fire, melt mixing cups, etc.

The trick is to keep it in multiple small batches, or pour it in something like a paint tray (so it stays in a thin film). It keeps the chain reaction from happening so fast.

As the epoxy and hardener react they expel heat (exothermic reaction). Heat causes the reaction to happen faster, which puts out more heat, which makes it happen even faster, etc. Can be real dangerous if you mix large amounts, not to mention the hot fumes you're inhaling.

knightsofnii · Post by **knightsofnii** » Mon Jan 17, 2011 8:23 pm

Usually only happens that way when mixed incorrectly. Though ive heard of some who need no heat for their press because the epoxy exotherms so much. The stuff i use will not kick at room temp. Rewuires heat to cure. The hardner is nasty on its own and will vaporize rapidly and can knock you back if you get a whiff of.it... but once mixed the stuff is stable. I mix whole batch at once no problems. Ive taken an hour.for.layup no problems... love it

Brazen · Post by **Brazen** » Mon Jan 17, 2011 8:38 pm

Sounds like what I use, it's not exothermic at room temp.

SHIF · Post by **SHIF** » Mon Jan 17, 2011 11:12 pm

knightsofnii wrote:...The stuff i use will not kick at room temp. Rewuires heat to cure. The hardner is nasty on its own and will vaporize rapidly and can knock you back if you get a whiff of.it... but once mixed the stuff is stable. I mix whole batch at once no problems...

I'm curious, what epoxy are you using?
Same question to Brazen.

I use QCM 0043 + 408 which gives me almost an hour of working time.

-S

skidesmond · Post by **skidesmond** » Tue Jan 18, 2011 4:47 am

I mixed a small batch incorrectly once. I mixed 2-resin to 1 hardener instead of a 4-1 ratio. Left it in a cup and it melted the cup and was hot, not enough to fry an egg, but very hot to the touch.

Also, Lost track of which cup I had mixed for a lay up. I had 3 8-oz containers of resin and 3 2-oz hardener ready for mixing. I mixed one batch and momentarily loss track of which cup I had mixed during a layup. Minor panic attack.

hafte · Post by **hafte** » Tue Jan 18, 2011 7:41 am

When your trimming the flash from a new pair of skis with a scroll saw make sure that you are cutting away from your table or the part is over hung far enough. I now have a 6 inch cut into my router table.

I thought I had burned out the blade again. Good thing it was home built AND I was intent on replacing it soon... I just didn't want to HAVE to do it right now.

And been there done that with the epoxy too. I was making tip reinforcements for canoe paddles and found out that you can generate a lot of heat with thick batches of epoxy mixed with chopped FG in a tin foil mold. I had to throw it on the floor and evacuate the shop until the smoke cleared.

Hafte

Brazen · Post by **Brazen** » Tue Jan 18, 2011 8:56 am

SHIF wrote:
knightsofnii wrote:...The stuff i use will not kick at room temp. Rewuires heat to cure. The hardner is nasty on its own and will vaporize rapidly and can knock you back if you get a whiff of.it... but once mixed the stuff is stable. I mix whole batch at once no problems...
I'm curious, what epoxy are you using?
Same question to Brazen.

I use QCM 0043 + 408 which gives me almost an hour of working time.

-S

Hey Shif, I'm trying the QCM0043 / ECA032, so far, we really like this stuff

Some people hate it, some people love it. I love it.

Mongo · Post by **Mongo** » Tue Jan 18, 2011 10:33 am

a.badner wrote:OH MY GOD MAN.
DONT IGNORE THIS, THIS IS JUST PURE SAFETY!

( im probably over reacting right now but still scared me. )

DONT EVER EVER EVER... EVER! MIX 1/4TH A GALLON AND 1/16TH OF HARDENER ALL AT ONCE... EVER!

WHILE LAYING UP MY FIRST BASES, my tub of epoxy started to smoke and got extremely warm.

so i quickly open up the garage door and take out the first bases and throw into the snow. so i go back into my garage to abort the layup. while turning off the lights i noticed its way too bright out side. i look back at the tub and the base and they are on fire. ya. on fire

scary scary scary shit

super scared to ever mix epoxy again.

Small 100-150g batches in Keg (12-16 oz.) cups staged throughout your layup will always give the best results (Sorry for mixing Imperial and Metric units in the same sentence). ON3P's helmet cam layup displays a great timing sequence for epoxy procedure in using a drill press for resin/hardner mixing. I always have made small epoxy batch mixes from my current QCM blend to the West Systems mix I ran 4 years ago on my cold curing press. The exothermic capabilities doesn't ever warrant a large mix given the general layup timeline.

ben_mtl · Post by **ben_mtl** » Thu Jan 20, 2011 4:30 am

Bad ideas of the week (last 2 pairs experience) :
- Work when it's 13ºC in the shop... it's a huge mess, everything gets sticky on your fingers because of epoxy, resin doesn't flow that well... you get the idea : Heat !
- Buy some 4" carbon tape in a rush because you have to press a new pair and are out of this material. I only needed 1" tape but that was all that was available.. I thought "I'll cut it to width", WRONG ! it just splits all the wires when cut.... I ended up placing carbon wires one by one on the ski.. and 10 of them/side/ski = lots of time !
- Not tightening the mixer arm in the drill press... you start mixing some resin and it gets loose... and fly.. oops !

In the end, even though it was not the easiest layups, everything was OK and the skis turned out great... there are some mistakes I won't do again

hugocacola · Post by **hugocacola** » Thu Jan 20, 2011 1:32 pm

Dont forget, never to cut everything before layup, the VDS rubber, the carbon and the kevlar, it sucks have to take of the gloves to cut the materials....and get back to work...

skidesmond · Post by **skidesmond** » Tue Aug 23, 2011 4:29 pm

Why does epoxy hate me? Why? I warmed up the resin and hardener today so it would flow and mix easily. It was the consistency of maple syrup at room temp. I layed down the epoxy on the base and applied VDS. I heard crackling sounds behind me. I turned around and the cup melted and epoxy started to smoke just a little bit. Less than 10 minutes passed since I mixed it. I had to toss it outside. The ratio was correct, 4-1.

I know epoxy is exothermic. Perhaps the fact I used a 16oz red cup (you know beer cups) that allowed the heat to build up didn't help. IDK. So after that near disaster I mixed the next batch in the red cup and then poured it into the bottom 1/2 of a plastic gallon jug. At least the epoxy didn't over heat. I'm worried the epoxy kicked to soon before I got the skis in the press. Guess I'll find out in the morning.

sammer · Post by **sammer** » Tue Aug 23, 2011 6:06 pm

des... how much did you warm it up?
I'm guessing that's the issue.
Although a full 16oz cup has a lot of potential.
Depending on the speed of your hardener 10 mins seems a pretty quick exotherm.

sam

skidesmond · Post by **skidesmond** » Tue Aug 23, 2011 6:32 pm

I don't know the temp. I had a heat style lamp shining on it, 125watt bulb, not a heat lamp bulb. It was warm to the touch, maybe 90-100F? Just guessing. It was definitely easier to mix and spread. Guess I'll start saving plastic milk jugs for mixing.... allow for the heat to dissipate. I just hope the skis bond ok.

OAC · Post by **OAC** » Tue Aug 23, 2011 10:15 pm

Lethal epoxy! :-)

Honestly I've never heard of heating up the epoxy when mixing and before layup. In my case there are no limits how much one can mix at the time.
I have some practical plastic cups (I buy them locally with shrimp mix salad, yum, eat the mix, and then use the cup for mixing epoxy. Recycling when it's best!

) it can contain a 200g ready mix.
I also (try) to have a 1:1 ratio between FG and epoxy.
200g FG = 200g Epoxy

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Official "Problems" Thread - For Those Times