Post production clear coat help

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#1

Hey guys. I’m having a funny issue with trying to clear some part I make. My process to make them is infusion, and the parts come out of the mold pretty nice and shiny right off the bat. A light sand, clean and then a 2K clear all of the sudden reveals a ton of pin holes, despite the surface looking great right out of the mold. So I’m dealing with very, very tiny pinholes. I come from a body shop background so dealing with pin holes in body work I’m familiar with. I would essentially wipe a product on, very lightly sand, and then primer. I’m wondering if there is a product out there that would do kinda the same thing, but would need to be clear, or black since I want to just clear coat over it. The two things I came across were these:

http://www.loehle.com/loehle-aero-coatings/wonder-fil-pinhole-filler/

And this seems to be kinda new ish, and is geared more for the body repair field, but am curious if it would work as well. Plus, its dark grey right out of the bottle so should hide or disappear when cleared over. If it fills the pin holes, in theory you should just be able to come right over with a clear and be done.

http://www.evercoat.com/images/ePIM/original/704182-6.2011-440-Express-SOP-DIGITAL.pdf

If theres other options (I’m sure there is) I’d be curious to hear them. I’m essentially looking for the quickest, easiest way to get a clear on a part without the annoying pinholes.

#2

I have heard of the Wonder Fill, but wonder how clear it would be if just using a clear coat. The Evercoat doesn’t make much mention to what it looks like when dry, if it’s clear or not. I’m dealing with the same issue on a fairly detailed closed mold layup and am looking for a similar product, so this interests me. I have tried UV cure windshield epoxy for larger voids, which works very well and is nearly an invisible repair. Even clear epoxy resin used to fill larger voids will look milky if used to fill larger voids. Pinholes can be a pain, infusion is the best way to get the best results with few to no pinholes, since the resin is replacing trapped air, which is nearly impossible to get out in hand layup.

A in hold clear coat may help you with this issue. By applying the clear before layup it will reduce the surface pinholes, but you may still get voids under the surface between your nice clear coat and the part.

#3

Thats whats funny about it. I make the parts by infusion and you have to get like 2 inches away from the surface to see any imperfections, but when you clear it they really jump out at you. Some might call it “fish eye”. Thats technically a different phenomenon but looks similar.

Are there any UV stable in mold coatings that can be sprayed on, and laid up over pretty quickly? I’ve seen some but they seem to have really long cure times before you can lay up on top of them. Not good for a production environment. Hence the want to be able to make a batch of parts, prep them quickly, and clear them all at once.

#4

I am pretty new to pre layup clear coating, and due to the production requirements it is very time consuming for what I do. There is a good thread about it here http://www.compositescentral.com/showthread.php?t=7622

#5

I just tried a few quick tests and made a post on that thread. Thanks for the link.