Gel coat problem

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#1

Hi guys I have a big problem

after spraying gel coat looks nice
but that`s the problem
after 1 min of spraying gel coat

plug: aluminium and the plug size is 20x15cm
release agent: Frekote 770-NC
gel coat: epoxy tooling gel coat +10%acetone +red pigment
under the plug is glass +Frekote 770-NC

any help ?

#2

I don’t have any experience with epoxy gel coats. I didn’t think there was such a thing. I always heard it was a major health risk to atomize epoxy.

If that was polyester gel coat, the first thing to try would be spraying a very light initial layer, letting that setup a bit then hitting it with thicker passes. It’s a technique that takes a bit of work with timing and amounts.

#3

i havent used epoxy tooling gel, but maybe if you tried brushing it on , without acetone ( i guess you used it to make it thinner? )

#4

I don’t think you should have added acetone. Maybe the FreKote didn’t cure before you applied the gel coat…we are talking about polyester tooling gel coat? Could also be your dye is not compatible with polyester resin/gelcoat. Possibly the acetone reacted badly with the FreKote? You definately have a product incompatiblity problem.

#5

you should use MEK to reduce the gelcoat

#6

Don’t spray epoxies.
Don’t add acetone to thin.
Your release agent may not be compatible with coatings. Some very high slip releases can cause this.

#7

yes, I use acetone to make it thinner but when I brush it without acetone it`s the same

its first time whene I accetone but efect are the same without acetone I apply gel coat after 24h when I apply last layer of Frekote We are talking about epoxy tooling gel coat Acetone didnt react with Frekote

I asked about this in factory where they produce my epoxys
I can add acetone but no more than 20%
and I can spray epoxys when I use recomended filters to my mask

#8

a common problem with semi-perm release agents is coatings and gel coats splitting like this. We use 770-nc and its just about the highest slip one you can get. If we spray duratec or gel coat it takes a really heavy coat to get full coverage or we apply one coat of wax over the semi perm and that solves things. I think you will find its the 770nc isnt compatible.

#9

I plan to spray 3 coats of gel coat but when I saw splittings I spray the rest:

next time I try to apply one coat of wax over the Frekote

normal curing time of my gel coat is about 1,5h but when I add 10% of acetone curing time was 10h :mad:

#10

wow, didnt catch on to the fact it was epoxy surface coat. like TET said, you do not spray epoxy, it is very bad for your health. the best method with a epoxy surface coat is to use a plastic squeegie or brush depending on how thick it is. the acetone should never be mixed in with epoxy

#11

Adam, you could try some silicone free ceara/carnuba style wax & shoot some pva at it before gelcoat, I think if the epoxy gel will spray without thinning leave it out cos your turning a very low to nil shrink product into something that might(even though the “theory” is most of the thinner goes out in the spray tranfer), just look after the lungs- cant be any worse than shooting epoxy paint;) . All the best from Jeff.

#12

today standard 4coats of Frekote + 1coat of Partal #2 wax (silicone free)

thanks for help guys

#13

how to fast clean 770-nc from the plug ?
I use Frekote PMC but its time-consuming. Its any faster process of cleaning 770-nc ?

#14

Are you trying to remove all trace of 770-NC from the plug or do you want to re-coat the plug for the next part?

#15

I try remove all trace of 770-NC from the plug.

#16

today I bought FREKOTE FRP-NC,
“it should sovle my problem (770NC + one coat of wax)”
that say seller :rolleyes:

#17

FREKOTE FRP-NC

still the same problem