Clearcoat Chips - CF Guitar Content...
 

My Emerald X20 fell over and the cleacoat chipped in two places as shown. What's involved in patching these? Thanks....

First step is to find out which epoxy/polyester (my guess is epoxy) resin they used in the gelcoat layer (the layer above the carbon/resin layer). If it's an epoxy resin, in theory you should be able to get away with any epoxy, but I still strongly recommend repairing with the exact material they used.

If you want to go the epoxy route:

What they may have used (and what you should likely use unless you're going to try to copy theirs exactly) is the west system 105 with the 207 hardener:
https://www.leevalley.com/en-ca/shop...tem-epoxy-kits

Note the difficulty here is that you'll end up buying (and mixing, don't try to mix 3 + 1 grams unless you're really confident you can get the ratios perfect) way more than you need.

Make tape walls with a few layers of packing tape, and slightly overfill the hole. VERY cautiously touch it with a torch to break the bubbles. This should literally be 1/8th of a second as you quickly pass over the area. Put a layer of wax paper tightly conforming to the surface on top and tape that over your packing tape layer. Or do this properly with a vacuum bag and peel-ply, but that's very significant tooling for such a small repair.

You'll finish with a slightly raised surface. Sand this back to be flush (be very careful here, more work with a higher grit is better than cutting through the surrounding gelcoat by accident), and polish.

I don't know the material of the fingerboard but the clearcoat looks a little thinner, and in a difficult place. You may have to set two batches (one on the side, and one from the top of the fingerboard), to ensure it sets level.

No comments on what that will do to your warranty.

The "usual" approach is to use CA glue to "drop fill" the area. Once hardened, use a single-edge razor blade to scrape level, then sand with progressive grits of abrasive, followed, usually, by two or more abrasive rubbing compounds.

It's a relatively easy fix for a professional. Perhaps not for someone if one doesn't have prior experience.

I wouldn't use epoxy, regardless of what the original finish is.

I like CA for those fixes too. Drop some CA in some sort of plastic container, I keep old packaging plastic around for this reason, then use a toothpick to dab just a small drop on the tip and touch the tip to the center of the chipped out hole and it will wick and fill in. Repeat till just above level then scrape back as mentioned above.

A nice tip for using a razor blade is to put some 'Scotch' tape over the blade on both sides exposing in the middle the blade about the same width of the repair area. Then you can scrape away without damaging the surrounding area. Of course then you will only scrape down to the tapes thickness but then a good wet sand and buff after that will level everything off. I also round off the corners of the razor blade with a file.

CA dries much more brittle than epoxy - I guess these aren't areas that are flexing, but would cracking not be a concern?

It certainly sounds like a simpler solution than mine

Glu-Boost was specifically designed for this, it's actually flexible. But people have been using regular CA for years too. And especially on that CF guitar it wouldn't be expanding and contracting anyway.

Thanks for the support and suggestions. I found this video by Dan Erlewine to be very helpful in showing what several of you have described. I initiated this thread thinking that I was going to sell the guitar and wanted to show potential buyers how easy a fix this would be. I've since decided to hang onto it. I've completed drop-filling and strip sanding with 400 grit wet & dry and am awaiting a StewMac order for micro-mesh higher grit papers https://www.stewmac.com/Materials_an...hing_Pack.html to proceed...