Archtop Finishes Information Thread

[NSJ]

I'd like to get the straight dope on guitar finishes, how they affect tone, wood, the aging of wood over time, etc. On the one hand, we have the following opinion (quoted from another thread from another site)--

"The difference between NEW guitars with Poly and Lacquer is very slim, but in 30 years, the difference will be very noticeable.

Nitro breathes (not the wood) and poly seals the wood off from the ouside world forever, and thus there is no aging process with a poly finish. On the other hand, nitro never completely dries and keeps getting thinner and thinner. This is a very desireable trait.

IMHO: When a guitar maker does not finish their instrument in Lacquer, they are sacrificing tone and quality in the name of manufacturing and monetary savings. They are not choosing poly over lacquer because it sounds better. It takes more time to spray lacquer, it takes more time to dry, You have to spray more coats, and you have to be very carefull when buffing it.

Also, when spraying lacquer you use PORE FILLER before spraying a nitro sealer coat on to the bare wood. This solves the lacquer sinking problem mentioned before as an old wives tale. Gibson and Martin do not use a plastic sealer.

I'm not surprised to hear that Fender did use a plastic sealer...shoot...they decided to BOLT their necks on to their bodies. They were willing to cut all kinds of corners."

and then we have ANOTHER opinion--quoted from another thread from another site--

Opinion #2--

"After painting over a few thousand guitars and a few hundred of them nitro.... I dont hear a difference. It is how thick and how hard, not the type of material. ALL finishes let the wood breath. Otherwise your maple neck would never move when painted with Acrylic urethane and I promise you that they still need adjustments. Also Many old Fenders were not nitro, just a nitro topcoat, they used fullerplast to seal and Acrylic lacquer colors. Leo just choose the softest easiest to buff and repair topcoat."

what is true and what is folklore?? seems to me the one thing that is certain is that you want the finish to be as THIN as possible.

[Franz 1997]

I've just been enjoying the, er, 'debate' on this very topic in the sadowsky thread near this one, so I'll join in here. The nitro vs poly thing does arouse some energy...
Anyway, one factor that hasn't been emphasised too much so far is that of appearance..IMO lacquer just looks nicer as it ages, checking and all ( and as been said above, it can be repaired, which is helpful when compared to poly)
A lot of the nitro mystique came about simply because poly has ( NB has) been associated with cheaper instruments, and the association still sticks, rather than these finishes being assessed on their merits. I'd certainly prefer nitro - but for looks, not effect on sound.

Personally I believe that the finish is one of the least significant factors in the instrument's final sound - try listening to the difference between spruce and maple tops on otherwise identical guitars, for example, or the difference between 11s and 12s, and it puts the poly vs nitro thing into perspective.

'course, that doesn't apply to the ibanez 175 I got off ebay that came covered in boat varnish.....now that didn't sound too good!

[Archie]

I'd join in this discussion, but I know nothing about guitar finishes, like nearly everyone else who participates in these discussions on the internet.

[spiral]

Non-luthier opinion here:
My experience has been the finish thickness and body construction has more to do with it than the finish material itself. I had two guitars with a very very thin matte poly finish, and i thought the guitars (acoustically) sounded open and as nice as nitro guitars i had. I also had a poly finished Gretsch that looked like it was dipped in a syrup and the body sounded pretty muted. Just for ease of care i would rather have a very thinly finished poly guitar, but they are pretty rare in the upper-end of quality instruments.

There could be some truth to the breathing and aging but i would never notice the difference or be alive long enough to ever be able to tell. As for as poly sealing the wood forever, i'm not sure how that could be true on a hollow body since the wood is only sprayed on the top, not the inside.

Originally Posted by Franz 1997

Personally I believe that the finish is one of the least significant factors in the instrument's final sound - try listening to the difference between spruce and maple tops on otherwise identical guitars, for example, or the difference between 11s and 12s, and it puts the poly vs nitro thing into perspective.

+1. This is where i am. Hopefully NiAg will be along to drop some science.