How can I tell if it's polyurethane?

[RandomHero]

I've got a couple guitars that I'm going to be refinishing soon. Simple solid colors and metallics, according to Guitar Reranch. Also according to them, though, I can save a lot of time by simply sanding my old poly finish with a rough grain and using it as a primer - that is assuming I have poly finishes on my instruments! Neither of them are particularly expensive guitar, so I expect they are, but how can I make sure?

[Runewalker]

RH:

Poly or Lacquer:

I dropped a bod one time accidentally on the sidewalk. While it rang like a bell as it bounced off the concrete, I do not recommend this approach for testing "resonance."

I tell that little anecdote only because when I went to remove the finish, I bought some Strip-ease to try to bubble it up. The finish laughed at me, saying, "That's it, that's all ya got?" So I went back to the hardware store and bought the industrial strength Stripeaze, guaranteed to melt the tattoos on a biker's ol' lady. Again, but in a louder more belligerent voice, the finish laughed like a Satanic Santa Claus MC Hammer, "HA HO HA, ya gotta be jokin', --- 'can't touch dat...."

So in a moment of brilliance, I thinks to myself, gee, "this must be poly." Hardly a nip on the finish, only in the pickup routs where it was rougher and unpolished.

Lacquer will respond to removers more readily. You might try a little acetone (which is sold in cosmetic aisle as nail polish remover, if you don't want to go to the hardware store) dipped lightly in a cloth and rub in the spring or pup cavities to see if the finish removes easily. If so it is lacquer. The poly I had also laughed at that test.

This is where I falter --- Ok, one place I falter ---- if the poly can provide a 'primer' base, why can't lacquer do the same? Scuff and paint, or are you worried the solvents in the new paint will partially melt the nitro?

While we are on the subject of painting guitars I have been trying to get your attention via PMail and this thread:

guitarnuts2.proboards45.com/index.cgi?board=guitar&action=display&thread=1146935149&page=1

Where I ask you and your sales colleagues at GC which colors sell the most for strats, back-routed strats and Jackson bodies?

If you could poll your friends at CG and search within yourself (to find inner peace?) in answering that question it would be very appreciated.


Here's a link on paint removal, that is handy, but not exactly the direction you are going. But all of us, not just Robt. Johnson and Eric Clapton, all us at some time stand at the Crossroads.

www.wenzel.com/documents/paintremoval.htm

The end of that dropped bod story is that I ran across a guy who desparately wanted one of those 'looks like it's been through 10 yrs of road tours and Keith Richards Jack Daniel Cabinet" reliced guitars. Not my esthetic, but I took the belt sander to it and made it worse. Attended to the playability and put a modified Jimmy Page wiring scheme in it. He is thrilled. Go figure.

[RandomHero]

I'd be happy to do the poll, but am sad to say I no longer work at the local GC. I got canned, for violation of company policy. (I used another, higher-ranking salesperson's approval password on the terminal in order to bring a customer-appeasing close to a deal involving a -very- irate customer.) They had to can me, but still like seeing me around and hook me up with employee discount. Cha-ching. =D

The FAQ on ReRanch never said exactly why poly can be used as a primer and not laquer, but I bet it has something to do with lacquer's tendancy to shift, soak in and out of wood, and generally move even years after its initial application... whereas poly finishes, like you said, are tough as a rock and are hard to budge one way or the other. Thus making much more stable bases.

[Runewalker]

I searched a bit and every thing I saw said if lacquer, strip it. I tried that once on a date and was turned down forthwith. I think she thought I said liquor. --- which has an entirely different meaning.

What are the bodies from? And are you doing the necks as well?

[RandomHero]

One of the bodies is my beloved Diamond Series Schecter. It is this most icky color of dark metallic green that I think I could have gotten a guitar in. I believe burgundy or deeeeeep red would be better fitting to the black hardware and ebony pickup mounting rings... =D

The other one is my buddy's straight black Fender Prodigy. He likes it black, but we're heavily considering plugging the trem rout in favor of le Schaller roller bridge. Though, switching from a Kahler, which included a locking nut, I am beginning to wonder if a bridge sporting fine-tuners may not be the proper way to go...

[sumgai]

RH,

Lacquer doesn't shift as you describe it. If it did, it wouldn't 'weather check'. That results from the finish being unable to shift with the changing conditions surrounding it. The finish is able to 'breathe', allowing wood to vibrate through it, but it is unable to expand/contract on it's own. That's the attraction of lacquer, it allows tone, and looks like a dream. However, poly finishes protect the wood better. Too bad they kill tone, by comparison. (We've been down that road before, so I don't intend to re-start that topic here. I'm just making an observation, that's all.)

Rune's suggestion about going under the pickguard is good. Where that's not available, you might be able to go under a bolt-on neck's screw plate, or under a bridge, if that's covering some small part of the finish. Be aware though, that often this is only a primer coat (inside of any cavity), and it may not be the full coating that one sees on the finished portions. This would be true for early Fenders, but not the later ones (CBS era and later).

Poly coatings are made to be durable. I even had one once where I dropped it on the floor, and the wood was dented, but you absolutely could not feel the dent in the finish! Amazing stuff. I am unaware of any over-the-counter product that will reliably strip it. Hand labor (or hand power tools) is the only method I know of to completely remove it.

And no matter what they say about leaving some of it as a primer, I would not use a lacquer over the top of that. The stuff wouldn't be able to soak into the wood, and would flake off in short order. Once poly, forever poly, that's the rule. (Which can be broken, given enough power sanding. But that's likely to alter the shape of the body!)

HTH


sumgai