Acoustic Guitar Construction

I think real nitro lacquer, like we used before the Great Flood, :>) has been fazed out slowly over the last 15-20 years...and I think most of it only shows 10% or so on the MSDS..(And I could be Waaay wrong?) but does it stay soft for you Tony? Your stuff looks sooo good...
I mean..usually it takes like 3 months or so for nitro to fully cure ..sometimes up to 6 months depending on how it was applied and the weather where it lives...but you know...shows fingerprints, case prints...dulls out and has to be finished sanded and polished again...has guitar stand Pox...and so on..or does the Deft brushing lacquer really set up and not shrink given time or continue to cure over the long haul?
Just curious... Thanks,

Ray :>)

Jackspt28 wrote:Ok , so I level sanded after three brushed on coats and made the mistake of sanding through the finish and the zpoxy on one the side near the waist. I went back and rubbed zpoxy on with my finger , made it smooth, let it dry a day and the scuffed the spot with 220. I then sprayed two coats of Deft rattle can clear over the whole guitar, It flowed out like glass, I then noticed the area with the sand through seem to have wrinkled or reacted?? I will let it dry for a couple days and then try to sand it out and retry. Any suggestions !!!

Jack, if I understand correctly, you sanded that area a little too much and cut through, and then after re-applying the zpoxy you sprayed lacquer over the whole guitar. I'm certainly no expert but I think you'll need several more coats of lacquer just on that area (versus over the whole guitar) in order to build it up again. In other words, you created a crater (a very very shallow one), which needs to be filled and then overcoat the larger area rather than spray the whole guitar and not fill in the crater. I had a similar situation where there was a small scratch in the top, so I sanded it out, re-applied lacquer, and ended up with a wrinkly circle/depression . I suspect this is because the new lacquer melted in to the previous lacquer (It looked like it melted all the way to the spruce, which honestly freaked me out), and would require several more coats in order to build up to a level higher than what I sanded down to. After applying about 5 more coats using brushing lacquer, with slightly increasing diameters with each coat, I let it dry for several days and then lightly sanded it back. After the final polishing it all came out fine.

Ray I have to say that your conclusions/experience must have something to do with your location or process and my guess it is not a product related problem, I have used Behlens, Mohawk, McFadden, Deft, Minwax, Sherwin Williams, and Watco and have never seen or experienced the drying problems you mention -- brushed or sprayed. Ten days is the max Iv'e waited. As a matter of fact Preston Thompson only waits a week or so before final polish and his guitars are marvelous and $$$$$
There's hardness/cure/drying test that's done with different pencil leads I'll try and find it.

RayRay wrote:I think real nitro lacquer, like we used before the Great Flood, :>) has been fazed out slowly over the last 15-20 years...and I think most of it only shows 10% or so on the MSDS..(And I could be Waaay wrong?) but does it stay soft for you Tony? Your stuff looks sooo good...
I mean..usually it takes like 3 months or so for nitro to fully cure ..sometimes up to 6 months depending on how it was applied and the weather where it lives...but you know...shows fingerprints, case prints...dulls out and has to be finished sanded and polished again...has guitar stand Pox...and so on..or does the Deft brushing lacquer really set up and not shrink given time or continue to cure over the long haul?
Just curious... Thanks,

Ray :>)

I have definitely experienced what Ray is talking about. I have had guitars lacquered for two weeks or more pick up the texture of the case in the lacquer. It is very annoying.
Ray, when your guitars get the Pox from guitar stands, have you checked if the coating on the stand legs is vinyl or rubber? My brother put his guitar on a stand, it lives there always, and his is all messed up where the stand touches the box. I warned him, but he does not listen.

Ddietz, Yes, thats sounds like what is happenning, I will take your advice to build/ fill the crator up, I think the thin edges around the sand thru were reactivated and wrinkled by the sprayed on laquer like you mentioned, I will build it up maybe with some light coats to get it sealed over. The spray can Deft went on really nice glassy smooth, with alot of luster. Thanks for your help.

Drying problem --- my first trouble shoot would be -- recoating too soon, each layer has to gas off completely. Heavy coats (brushing lays down about four times the thickness of a drip free spray coat) takes much longer for primary cure (Tony I know you don't call it that) So if the solvent gases get trapped they soften the next layer and so on --- $.02

Thanks Ken, It is going to sit for two days as I will be away this weekend, hopefully this will help with drying.