Gel coat hell!

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#1

Anyone have any advise on keeping the gelcoat from not crackig or should I say chipping out off the edges of my parts?

The only problems I have are when I release the part and right along the edge (what I would cut off the flashing from) gets chips out of it. Some are so small that I could grind it just a tiny bit and be happy…some need to be fixed though.

I dont know if its that I am too thin on my gelcoat or if I need to put a bevel in my molds to help. My parts are 1/8" thick…well thats what the part was that I used for a plug. Ive not measured my finished parts.

I just dont want to be fixing them all the time when I know there is something I could do to make them pop out with no problems…

anyone? oh and its all PER based

#2

SO the chipping occurs when the part is trimmed to final size? Perhaps try a different method of trimming.

#3

How are you trimming out your parts?

From what side are you cutting from?

Are you spraying the gel coat to what mil thickness?

Do you let it fully cure before laying in the reinforcements? Or, just letting it “B” stage and then laying the reinfoircements in?

#4

Good point there Werks, it sounds like the gel coat has cured before the laying in the reinforcement leaving only the mechanical or adhesion bond. I have seen this before where you might spray in some clear gel coat into a mold, let it cure, and then infuse with epoxy over the cured PER gel coat.

#5

I thought epoxy would stick to per if there is no wax, but per wouldn’t stick to cured epoxy. Maybe the per you’re using has wax?

#6

most of the time when I lay my fabric in, I have enough tack left in the gelcoat that it will leave a finger print and sometimes it will let me take just a tiny bit back off with my fingertip.

Im not sure of the mil thickness…my mil gauge isnt too friendly for parts with flanges that arent dead flat. Ive not tried to stick the mil gauge in the mold surface for fear of messing up my gelcoat.

Me and PERF talked about it and it may be air voids from leaking infusion seals…he says the air travels along the edge of the parts first.

what ever it is, Im tired of it. I get a 98% perfect part only to have to repair some tiny chips in it. those chips are what keeps me from running full tilt with this