French polish beginner questions

Fliss · #1 04-01-2010, 02:33 PM

I'm a way off being at the French polishing stage on the old guitar I'm restoring, but I've got the shellac, I've watched a few instructional videos on YouTube, and got a few hints and tips from a luthier, and I'm experimenting on a cheap old wooden box to get a feel for how to do it. After a couple of quick coats, my box is looking surprisingly good, but I'm leaving it till tomorrow before I think about adding any more. Meanwhile I have a few beginner questions if someone can help please.

My first question is, how many coats do you give it before you call it done? How do you know when you've done enough?

Also, when you get to that stage, do you need to do anything else to finish it, such as buff it with a dry cloth?

And while I'm asking questions, when I get to do it on the guitar, there's no finish on the soundboard, but there is lacquer on the back and sides. If I French polish over the lacquer, should I sand it first?

Fliss

Coke_zero · #2 04-01-2010, 02:48 PM

www.luthiersforum.com register and look at the tutorials section and you can't go wrong. I have seen a Youtube video of a Scottish furniture maker turned guitar maker who French Polishes the guitar inside & out (he believes all wood should be finished, mainly due to his furniture making background). On the outside he does a fair amount of coats over a period of 12 weeks.

WhistlingFish · #3 04-01-2010, 06:01 PM

I guess everyone has their own take on the techniques involved, but the "go to" tutorial for many years has been the one put together by the Milburn brothers. Have a look at http://www.milburnguitars.com/frenchpolish.html

marioed · #4 04-04-2010, 05:53 AM

I used the Milburn tutorial as my main guide to french polishing on three of the guitars I've built. It is a pretty complete guide. As to your questions and using Milburn for reference to terms, I do 6 to 8 body sessions followed by sanding with 600 & 800 grit. I then do 3 or 4 more body sessions and 4 to 6 glazing sessions. I like to let the guitar rest overnight between sessions. Once I get the finish where I like it I polish with micro mesh starting with 1500 grit and going up to 12,000. I then hand buff with Meguiars's #7 Show Car Glaze. Unless the side and back finish is in bad shape and you want to refinish the entire guitar I'd suggest you leave it alone.
Regards,
Ed

Kitchen Guitars · #5 04-06-2010, 01:13 PM

I'll note there was a 10 year old Milburn with flakey finish on AGF Classifieds a few weeks ago

I don't know what caused it.
Stew Mac just sent out a tips email on a simplified French Polish proceedure. If you watch Youtube, follow Milburn, watch Stew Mac, take a David LaPlante class and buy the Fernando disc...... you now have 5 different ways to do it.
Look at them all. Cool thing with French polish is it wipes off so you can start over. The uncool thing is it wipes off so you can start over

WhistlingFish · #6 04-07-2010, 02:43 AM

Quote:

Originally Posted by Yamaha Junkie

Cool thing with French polish is it wipes off so you can start over. The uncool thing is it wipes off so you can start over

How true! Note, however, that there's now an alternative product in UBeaut's Hard Shellac which promises all the advantages of a traditional french-polished shellac finish with none of it's shortcomings - if you believe the marketing hype. I note that it's now sold in the US through LMI.

I have limited personal experience with it, except as a sprayed finish. My own brief foray into french-polishing with Hard Shellac yielded mixed results, but I'm sure that can be attributed to my own limitations rather than those of the product; others have reported great success with it.

Kitchen Guitars · #7 04-07-2010, 04:31 AM

I have read avoid premixed shellac but LMI has it so maybe the hurdle has been crossed

WhistlingFish · #8 04-07-2010, 05:23 AM

Quote:

Originally Posted by Yamaha Junkie

I have read avoid premixed shellac but LMI has it so maybe the hurdle has been crossed

It's said to have an 18 month shelf life and the expiry date is marked on the bottle. It's certainly worth considering if you're interested in a more durable french-polished finish.

sharkydude50 · #9 04-07-2010, 08:53 AM

How does French Polish stack up against these other two- specifically around durability and sonic properties?

marioed · #10 04-07-2010, 05:39 PM

Sharkydude,
I'm not sure which two you're refering to. French polishing is a method of applying a finish not a type of finish like nitro, poly or varnish. The actual finish material used is shellac. I've never used the U Beaut Hard Shellac myself but from what I've read it gives a more durable finish than regular shellac. I was recently given a jar of it and plan to do some test pieces with it when I get the chance. Shellac is supposed to be the most acoustically transparent finish for guitars but it is also the least durable. On the plus side it is very easy to repair a shellac finish since in french polishing the shellac is an amalgam rather than seperate layers and the solvent is pure alcohol.
Regards,
Ed

Fliss · #11 04-11-2010, 09:18 AM

Thanks for the replies folks, all very useful. The lacquer finish isn't too bad, except a small area where I've had to patch the binding, and some areas around the headstock, so I'm not sure what the best approach will be for these areas, but I'm pretty sure the shellac will be the way to go for the top, which seems to have no finish on it at all.

I'm currently experimenting with premixed shellac, and have got a small bottle of the Liberon branded product. I tried it out on a cheap old wooden box, just a couple of quick coats to get a feel for it, and it seems to have dried well.

Fliss