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Or should I put vinyl sealer down first or something? I get the impression this stuff will stick pretty well to a lot of things. I've only used it previously for automotive touch ups, and have applied it with no problem over scuffed clear.

The exact finish I intend to use is from Sherwin Williams, called Finish1 fc 710. Pore fill will be z-poxy.


***Update, 6/24/2016***

Didn't work out so well. This finish works great on the car! Lays down really nice and super durable. I will definitely continue to use it for automotive work but will not use it anymore on guitars for 2 reasons.

1.) It didn't play nice with the epoxy. There were fish-eyes and craters everywhere...I'm not really sure why but my conjecture is that because the primary solvent in this is MEK, it actually dissolved epoxy. My conjecture is that this softened the surface, essentially contaminating it...kinda like it burnt into it, except in a bad way. You may have to zoom in on these pictures to see it.



This wheel was finished with the exact same finish, from the the same gun sprayed in the exact same manor. As in the previous images, this is what it looks like off the gun. My conclusion is that clearly the finish just wasn't happy to be on top of the epoxy.


2.) My nose and research tell me it gases of formaldehyde for a really long time. Long time as in, years. This isn't healthy for customers.

Conclusion: I'm going to shop around for a different catalyzed urethane for guitar use. Mohawk has some stuff that looks good. I'll try to make another post when I've found something.

PS. Are you thinking of spraying a Catalyzed Urethane? Before you do so, please research isocyanates and make sure you are equipped to not breathe any. Use a supplied air respirator. This is really important. A normal activated carbon respirator is not enough.

I believe that Tony Ferguson who is a pro finisher and has done some of mine in the past sprays cat urethane directly over West Systems pore fill and wash coat. Some of my guitars that he did are around 10 years old now, been out and about and no problems for at least the first decade.

Back in the day our resident OLF expert on some finishes, Michael Payne used to say that shellac sticks to epoxy fine but epoxy has issues sticking to shellac. That's been my experience too.

Ask the manufacturer. Sherwin Williams has ALWAYS been great with respect to getting me good information about the use of their products.

I bet they'll say to sand it to 240 to give it a tooth, clean the surface well with solvent, and spray away.

Tony has done three of my guitars and they are stellar finishes. Although I can't remember precisely what he said (he DID tell me the whole finishing schedule) I do believe this is what he does. I think he's using a PPG product...but that shouldn't matter.

_________________
I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Prep out the epoxy at 320 grit and spray. should be no problems.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/