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I've always been one to say that only a master builder should take on students but my nephew has taken an interest in building a Flamenco guitar and he's a good kid so...

Hes coming to town for about 10 days.

I have built a guitar in a week but of course the finish takes me forever. I may end up sending him home with a guitar in the white.

Anyway if anyone has ideas on how to speed up the process I'd love to hear your tricks. Seems like starting on the top is always best and then bend the sides and get the back ready. Titebond all around and CA for the decorative stuff.

The bending machine will help speed things up too.

We talked about using a shellac finish which is what I use almost exclusively but that's the tricky part. I can speed it up by using a brush on the first couple coats and then French polish and have it looking good in a couple days but making it perfect is a never ending task.

I've only used Tru-Oil once and I like it a lot but I don't remember if it's a 'fast' finish.

It will be Cypress so filling is not part of it which is good.

You can French polish a guitar in a day. In fact, that's how Richard Brune teaches it. The fact that you don't need to pore fill the Cypress will be of great help.

Be careful with CA though. We all know what it does to Spruce, but I don't know if Cypress is different in that regard.

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For the finish, have you thought about trying the azeotropic mixture of shellac, alcohol and acetone described in the Gore/Gilet books?

I'd highly recommend Kevin Aram's process for applying liberon finishing oil. It's quite quick, shouldn't take more than 2 days to apply and another day or two to dry, and has a lovely aesthetic. The prep work is a bit more intense (after 300 grit you switch to micro mesh and sand to 2400 grit) but the matte finish is attractive, protective, and a bit nicer than tru oil in my opinion. Here's a link to the issue of American Lutherie in which Aram outlines his process and photos of a guitar I recently built with this finish. I was crunched for time with this guitar and decided to go the oil route instead of French polish but it definitely didn't look or feel like a compromise. I received many compliments on the finish from professional guitarists like Laura Snowden, Joao Luiz as well as many amateurs and enthusiasts.

https://luth.org/journal/american-lutherie-127-fall-2016/

I recommend my wipe-on shellac finish described here http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=55577&p=729484#p729484

I’ve done ukulele workshops with kids. The shellac + acetone that Don recommended works really well.

You might also consider Osmo? I really like it for necks but if you aren’t after the all allusive 101% tone it could work for the whole instrument.


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You might joint and glue the plates ahead of time so that the moisture can get out if the joints before you scrape or sand it. You can have him joint another top and back for the learning, but the ones he’ll use might do better with some drying time. Personally, I wouldn’t deny him the joy of hand bending on a pipe. It won’t really take that long and he’ll feel like he’s done something when he finishes.

The LMI PVA glue sets up and hardens a bit faster than Titebond. You can gently work things in two or three hours rather than overnight.

The french polishing is something he can take home with him to continue. You’ll just have to gift him some shellac, some alcohol, and a pad. Robbie o’Brien has a one or two day process using 1 lb cut that dries very quickly. His is more of a shellac application process than what I consider true french polishing in that there’s no hard rubbing or friction heat. (When I do it, it takes many days—as long as my patience lasts—and I’m never really done. I just stop at some point).

For express emergency finishing I recommend Wurth nitro-alkyd lacquer aerosol (part no: 0893351920)



You can recoat in 20 or 30 minutes, and four coats will probably do for an open pore satin finish. Scuff sand P600 between coats. Build is fast and the self-levelling is unmatched by any other aerosol product I’ve encountered. Final surface is all but indistinguishable from a well applied gun finish. After last coat, leave guitar overnight to harden before fretting, gluing bridge, fitting tap plate etc.

Product in cured state is slightly softer than a conventional nitro but in my experience is check-proof. Invisible repair is trivial - lightly sand area, overspray with same product. It’s not a perfect finish (what is?) but it’s impressive for a finish you can get on in just a couple hours.

Prep is as for nitro (eg pore fill if desired, sand to 220ish).

I was introduced to this product almost 10 years ago when I did a build course with Gerard Gilet. Since that time the guitar I built and finished with this product has been my daily player and it still looks very good.

Thanks for all the good suggestions. I'll have to look up that recipe in Trevor's book which I have but must have just skipped over that part since I have my own. Does acetone speed up the process?

Bob I had a good laugh at this because that is exactly my approach to it as well, I just never put it in words. "When I do it, it takes many days—as long as my patience lasts—and I’m never really done. I just stop at some point"

I love a Nitro finish but I am going to only use safe finishes on this one.

Yes, the addition of acetone is the thing that makes the drying go way faster than with alcohol alone.

If you want a less smelly approach (i.e., no acetone), a 1 pound cut of shellac dries pretty fast. That's the heart of the Robbie O'Brien method.

a Tru-Oil finish might be possible too. It takes longer to dry, but you really only need a few coats.

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I once finished a guitar in Pro Custom Oil satin, available in a rattle can. It is a "tung oil modified urethane" and it produced surprisingly good results. For pore fill, you can buy a regular can of their gloss and wipe on a couple of coats then wet sand with the oil to produce a slurry. Dry sand with 400 and spray the topcoat.

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Good judgement comes from experience. Experience comes from poor judgement.

In terms of speeding up the build part of the process, Robbie O’Brien has a video course for sale on his 6-day build process. A lot can also be gleaned from his social media posts.

John Greven is known for his rapid building, and wrote a couple of articles for American Lutherie #117 and #118 on his process.


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