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Basic Drop-Fill Finishing Question...Why's This Happening?

Im a guitarist and a tech-wanna-be, and I've done a fair amount of finishing, drop fills, etc. I've never had an issue with drop fills before. I've done a few dozen little fills on small dings and nicks like this and everything comes out looking/feeling perfect after the final buffing, but I'm a little stumped as to what's going on here. The pic is attached at the bottom of this post.

I wanted to get the neck on my 335 super smooth so I drop filled two minor little dings. I did what I always do for drop fills except this time I used lacquer to fill instead of super glue. Here was my process so that someone can maybe see what's causing this...

-Sprayed nitro lacquer clear coat into a little plastic cup, let it sit for a few mins
-Filled both holes by dropping with a little plastic toothpick
-Let it dry overnight
-Used Franks razor blade scrape trick to remove the bulk of the drop fills, got it pretty smooth
-Feather sanded with 600
-Wet sanded with 600>800>1000>1200>1500>2000
-Buffed with fine compound

Usually at this point everything looks/feels great and I follow up with some swirl remover, polish, etc.

Those two white areas feel totally different, almost like they were never buffed...feels like a satin finish. I know that the white is the compound and I can probably get it out with a quick naphta cleaning, but I'm puzzled as to why they feel "satin-ish" and not glossy smooth. The other weird thing is that the white areas are much larger than the size of the actual drop fills.

I would think this is a pretty obvious mistake that I made somewhere...anybody have any suggestions?

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From the pic, it looks like you buffed through the finish.  Does it feel like wood? Nitro shrinks and I would have not leveled or buffed out until it sat a least a week. 

Glen, I think you're exactly right. That would make sense why the compound looks like that too...its sitting in the pouros wood surface.

What's the best way to go about it now? Apply a thin coat of lacquer and let it sit for a week? Maybe spraying a coat would be better than painting it on at this point?

For what it's worth, I keep a small jar on the workbench with about an inch or less of old clear lacquer in it. Even though the bottle's capped, it's constantly thickening so I'll add a spoonful of fresh lacquer once in a while just to keep it semi-thick.   

Using that for drop-fills takes a lot of the "shrink" out of them, although it's still best to leave it for a week (or two or three, if you can) before any razor blade leveling.  The longer the better. 

Would applying it by hand definitely be better than aerosol at this point?

I'd spray it.  Clean it good and rough it back up with 220.  It's too smooth for good adhesion.  Let it gas off for a few weeks and blend it back in with your buff routine. Use an airbrush if you have one, if not, narrow down your pattern and lower the pressure.  Don't try to mask around it, just mask off the fretboard so you don't get overspray on it.  Good luck and let us know how it comes out.

Btw I meant to ask...are there any differences between nitro lacquer for instruments (like the stuff from StewMac, LMII, Behlen, etc.) and typical nitro lacquer that you can get at a hardware store (Home Depot, Lowe's, etc.)? For some reason I'm hesitant to use nitro lacquer that has a picture of a birdhouse on the can...

I'm confused,

It looks like bare wood to me.

looks like Lacquer in the two dings and the sanding around them went down to the wood.

Am I missing something?

Supposedly, stringed instrument nitro lacquer has plasticizers in it to keep it more flexible, longer.  As nitro ages, it gets thinner and thinner and more brittle. Temperature changes (shock) can cause it to craze.  The plasticizers supposedly prevent or lessen this feature. I've always used LMI nitros like Seagraves.  I say supposedly, because I've heard of others using common, quality lacquers from say from Sherwin Williams on their guitars with no problems and their opinions were that either all brands have plasticizers already or they don't believe the plasticizers really help.  It's your choice and risk.  If you buy locally, I'd buy from a well-known supplier like SW or other major coating manufacturer.

Hi Pete.

In addition to spraying the lac, you also have to clean any rubbing compound and other contaminants completely out of the raw wood.

Another major challenge will be matching the color. It's a challenge for veteran sprayers and will pose a huge challenge to a new practitioner. Be aware that the outcome will most likely not be invisible. Color/repair matching/hiding is not a "Finishing 101" job. It's advanced and takes many attempts just to get 'not too good' at it.

You're also dealing with a Gibson lacquer, which contains too many plasticizers. When I do a Gibson made after 2001, I usually refin the entire neck. Believe it or not, I've found Deft brand lacquer to be the most compatible with Gibson's lac. Available at WalMarts everywhere. It's inexpensive but is appropriate for the task.

And please don't take offense at this next suggestion:

Next time you undertake a project like this, ask us for "how to" advice before you begin. It's more fun and easier for us to coach you through doing it the right way as opposed to giving instruction on how to fix a mistake. I, too, learned this the hard way when I began repairing in the early 70's. The guy who told me that (loudly and in my face) was right on with his wisdom..

I also urge you to buy a few yard sale specials to experiment on. Messing up a $20 yard sale special definitely trumps messing up an expensive/quality instrument.

Best of luck in getting it back into shape. I'm sure you'll do fine with the advice you've received from the guys on the forum.

I just noticed this post and wanted to ask if this is an Epiphone by chance?

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