Help with Clear Gel Coat surface prep

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#1

I am doing a Carbon Fiber Polyester overlay project and am ready to spray a topcoat of clear gel coat. Everything has been sanded, washed and is papered and taped off ready to spray. I’m wondering what can I use to wipe down the surface before I spray on the gel coat. I have seen some mention of acetone and am wondering if this is what I should use. I want something that will dry quickly and not make a big mess in the spray booth while removing any dust and small particles for the surface.

Thanks…

#2

i hope the gelcoat has wax as gelcoats are not reallt designed to work like that,they are designed for use in moulds where they see no air,normal gelcaot will NEVER dry unless it has wax added to it.

#3

i would use a clear you can get in a rattle can or duratec top coat, and yes acetone would work to clean the surface

#4

Hmmm… That could be a problem. I have the “Crystal Clear” gel coat that Evan was selling on his site a while back. Does anybody have any experience with this product? Can I use it as I described in my original message post? If necessary could I spray PVA over the Gel Coat to seal it from the air?

Thanks…

#5

you can add wax to one without it.

#6

the gel coat will dry but takes long and it will not sand really at all. Just go to a automotive paint store and get the clear in the rattle cans and they also have UV clears to in the rattle cans and spray several coat and then sand and buff

#7

adding wax will help it sand as well too

#8

Thanks forr all the fast help…

I do need the UV protection. I will look into some spray clear, that sounds a little easier.

#9

glad we can help :slight_smile:

#10

Just a quick update to let you all know what I finally wound up doing and how it turned out.

After sanding the CF & poly lay-up job I wanted to build the surface up some and really wanted to do it by spraying the clear gel coat, so I got some Duratec Clear Hi-Gloss Coating from uscomposites and mixed it 1:1 with the gel coat. I first sprayed 1 thin coat let it set for about 20 min then sprayed a 2nd thicker coat let that sit for about 3 hrs then I sprayed a 3rd final coat and let it cure overnight. The next day the surface was smooth and dry (not at all tacky). I did have one small run (first time I ever used a gel coat gun) so I wet sanded everything with 800, 1000, 1500, then 2000. After sanding I buffed and polished it to a beautiful finish. I couldn’t be happier with the final result.

I’ll try and post a picture real soon… Thanks for all the advice.

#11

sounds good, I just had one question.
Why did you mix the duratech with the gel coat?

May be it is something I need to understand better.

#12

thats what i was thinking :? get the pics sorted :slight_smile:

#13

Well I’m pretty new to this so I’m not saying this is how it should be done just that it’s how I did it.

  1. I wanted to build up the surface a bit more and the gel coat is much thicker than the Duratec Clear.

  2. The gel coat I have has UV protection in it and the Duratec Clear did not.

  3. I could not find the clear spray paint with UV protection (I didn’t look real hard but I did look).

The clear spray would have been much easier but would not have built up the surface like I wanted.

#14

Duratec’s Polyester Clear Hi-Gloss Additive (Product # 904-001) is mixed in equal parts with gelcoat. I assume it could be used with a clear gelcoat. Doesn’t require a wax additive.

http://www.duratec1.com/ag07.html

#15

Devil dawg. I thought he was talking about the duratec clear topcoat 904-045
I didn’t realize hewas talking about the hi gloss additive.

Even so, I was wondering…with this combo. what kind of cure time did you experience. I like the topcoat, but would give anything to get it to cure quicker.

#16

I’m not sure exactly how long it took to cure. I let it set over night about 15 hrs and in the morning it was completely dry and ready to sand!

Here are some pics of the finished project…

#17

Very nice job. I think it all turned out well.

#18

That is what the duratec hi gloss additive is for. Mixing with gels

#19

everytime I add the additive to gelcoats it makes it fish eye