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I'm in process of starting an FP project and want to seal up the binding and inlay before pore filling.

On hand I have a can of Nitrocellulose Lacquer, but no thinner. Also available are Grain Alcohol, Acetone, Mineral Spirits, and turpentine.

Could someone please direct me to which of these products would best thin down a shot of nitro without blowing the house up? I could always just get some lacquer thinner tomorrow or this weekend, but don't want to add one more volatile liquid to the ever expanding collection I already have if I don't need it.

Thanks in advance for anyone willing to impart some knowledge on this.

Dave

I don't know how the nitro lacquer figures into your french polish project, but many people thin nitro with acetone. On my last guitar, it's ALL I thinned the nitro with. I'm sorry, but I have no experience with FP.

Undoubtedly someone with much more experience than me will come along to bail both of us out. Hang tight.

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Eagles may soar, but weasels don't get sucked into jet engines.

By "FP" do you mean a shellac or varnish french polish? If so, I'm wondering why you want to use nitrocellulose at all. Shellac as a sealer coat under nitro is common, but I see no reason to go the other way around. All I could think of it doing would be to cause possible adhesion problems with plastic bindings. Nitro is not so good directly on plastics, and would require a vinyl sealer to insure a good bonding.

As to the solvents, acetone is the only one you mentioned that would work as a thinner for nitro. Still, I see no reason not to just use lacquer thinner. And any of these solvents are highly flammable and shouldn't be sprayed unless you have appropriate ventilation anyway.

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Eschew obfuscation, espouse elucidation.

Thanks guys.

The FP schedule I follow calls for sealing the binding, and anything else that isn't rosewood or mahogany, with a lacquer dipped q-tip before filling the pores.

It will all get sanded off through the pore filling.

The binding is a REALLY bright white porous wood and I don't want to get any sawdust or pore filler in it.


That's where the crazy question about mixing lacquer and shellac same from.

d

The acetone seemed to work like a charm.

Binding, purfling, back strip and inlay are all sealed with the nitro, and the top is sealed with shellac.

d

Nitro is not a good sealer. It really needs a vinyl sealer to be applied to bindings, purflings, corners, etc., before applying nitro. Shellac is a great sealer as well, and will seal and adhere much better than nitro. I have to say, I'm a bit confused by that approach and am curious as to where it comes from. It can't conceive of a reason not to simply seal with shellac, fill, then go on with shellac.

Where does this method originate? I'm simply curious if the method actually makes as little sense as I see in it, or if there's something in a particular filling process that I'm missing here.

_________________
Eschew obfuscation, espouse elucidation.

Frankly if you are going to French polish (shellac) the guitar why use any thing but shellac? 1 lb cut fine artist brush will do the trick. Once the shellac set and cures over night you are ready to pore fill. The pore fill technique you are using shellac and end grain dust? Or Pumice type fill. i gather from what you wrote it is end grain dust and shellac as the binder. Still I think Shellac is the answer.

This sounds like my method of sealing the bindings/purflings/inlay etc. that you don't want to get dirty when using my method of shellac and end grain sawdust as a pore filler. The method of thinning some lacquer 50/50 with thinner and applying this solution to the areas like maple bindings etc. with a Q-tip is quite effective in keeping them form getting "stained" with the shellac and end grain dust which is usually dark. After pore filling, the area covered with the solution of thinned lacquer sands back to clean with little effort. You can then apply your French polish or lacquer or urethane or whatever else suits your fancy.
BTW, Shellac also works to seal these areas before pore filling. You need to be careful though if you use shellac and sawdust for pore filling because you can dissolve your seal coat with the alcohol in the shellac use for pore filling.
There are other methods of sealing and pore filling. This is just one and I find it highly effective.

Thanks for Chiming in Robbie.
After the interrogation on where I got the idea I was scared to divulge names so as not to incriminate my DVD mentor.
Glad the expert took onus for it.

And in the expert's defense, after spraying nitro on my first instruments, I was EXTREMELY pleased with the results of the french polish schedule I followed from his video. It is hard for to fathom going back to the booth after that experience.

I knew better than to post this message without a "don't ask" disclaimer.

Oh well, thanks as always for the advice and consideration given to all the posts on this forum.

Dave

Not to worry Dave. It's all good.

Happy Finishing!