Shellac/French Polish advice.. - created 01-28-2008
Wilkinson, Benjamin - 01/28/2008.06:28:42
Can anyone direct me to any URLs that give a good over view of Shellac/French Polish techniques and tips?
I'm finishing an Alder Telecaster Thinline. I've just started on my pice of scrap.. And feel a bit lost..
I know about the tampon technique (where you soak a pice of fabric with the shellac and then wrap it in another pice of fabric before application)
But the fabric drys out quite quickly after application.. Do I need to use another pice for follow up applications? Do I need to clean the fabric, how would I do so?
I hear its one of those things you just need to practice, so I've jumped in head first..
But I dont really know much..
Any help or advice would be much appreciated. :D
Cheers!
Benjamin, see our Links Pages under "Finishing and Refinishing" for a link to the Milburn tutorial.
The Milburn tutorial is where I learned FP.
It is somewhat magical. You can't really believe it works as they describe, but it does.
RE-fad/pad/muneca I use white cotton underwear material. I use a ball of cotton in side of this as the absorbent material. The outer covering will wear through, and it will need to be changed. I change it when it gets holes in it, or if it starts to look dirty. When I am pore filling with the pumice, it wears through fairly quickly. Between sessions, I place my pad in a tupperwear type of container. If it is still a usable pad, but is too dry, I squirt some alcohol on it, and it is back to functional usable status in about 30 seconds or so.
Use shellac flakes and alcohol to make your own. Use small squirt bottles to apply alcohol, shellac, and oil to your pad.
Don't spend more than 30 minutes at a session, and only 2-4 sessions a day. The shellac needs to harden some, and if you spend too much time in one session, you sometimes get a build up of a soft jello type mass on the surface which gets pulled off.
If you have further problems or questions, ask again.
Awesome! Thank you!
One more question.
I know Nitrocellulose lacquer can be used over Shellac. But can Polyurethane be used over the top just as Nitro can?
Nearly ANYTHING can be used over shellac- that's one of the reasons it's so well liked.
The Milburn tutorial is the best thing on the topic that you can read, anywhere. I would be less lazy I would translate in French to help my local friends who want to improve their technique. Two little points however merit to be quoted for beginners in FP:
1/ When you have loaded your pad with alcohol, a little shellac dilution and, superficially, a tiny amount of olive oil, you'd better begin to FP a little hardwood board that you would keep for that use. Say a dozen of circles BEFORE you start on the instrument.
2/ When you finish your session of circular movements with a rather dry pad (takes usually five minutes for me) you re-load with two three drops of alcohol, you recreate the olive oil superficial treatment but YOU DO NOT RELOAD WITH SHELLAC for this second set of circles.Again the little hardwood board. Again five minutes with that almost shellac free pad.
With such two basic habits, FP can be a very simple technique.It really worked well once taught to me well. The very good Milburn tutorial can be seen as somewhat complex. FP is not complex when well understood.
Finally, FP is a bad way
I was taught to concentrate on the edges and the middle will take care of itself... :D
It's a very "forgiving" technique... don't get too caught up in the mystique and fine details until you are experienced... just sand down some scrap wood and rub some shellac on it, see what happens. First a drop of linseed oil, then shellac, etc.etc... Suprisingly easy at a basic level. Press the pad on a bit of paper to even out the load before you apply it.
Mirror glass finish is a longer story...
I have not heard of linseed oil being used with French Polishing. The oil is used as a lubricant. If it is a oil which hardens with time, it is felt by many to combine with the shellac and make a harder surface.
Linseed oil is used as a component of varnish and paint.
The most commonly used oils are mineral oil, olive oil, and walnut oil.
Other folks here have mentioned trying raw linseed oil in French polish - the kind you get in the healthfood store, not the kind you get from the hardware store.
I've used walnut oil and olive oil. The only difference I noticed subjectively is that the walnut seemed to want the cover replaced a little more often due to crusty dryness on the periphery. Not so much with olive oil.
Linseed will work, it's another drying oil rather like Walnut but 'heavier'.
When I was at school, my guitar teacher, who made his first classical in about 1950, would have had a fit if you had suggested anything but linseed oil for polishing...
Of course it must be raw; here, anyway it's available in any hardware or farmers merchants. In finland raw oil is called Pellava (Linseed) oil and boiled/cooked is called Vernis. (Think it comes from french for varnish??)
I see that Lee Valley sells a product that they call "French Polish". Their website says...
"It includes all three of the principal elements (alcohol, shellac and oil), plus a couple of other modifiers. The result is an all-in-one polish that is much easier to apply and that takes half the time and effort, while producing a finish that is very well accepted as an alternative to the traditional polish."
Has anyone ever used it? I can't imagine that it produces anywhere near as good of a final result as a traditional French Polish job.
Those are generally considered "padding lacquers" and have some harder resins and their solvents mixed in. Behlen's Qualasol is one such product. I used and liked Qualasol, but that was before I knew much about genuine French polish. I might stick with Qualasol or a similar product now, were I still building hammered dulcimers, if it proved on testing to be a harder finish than FP in the first weeks/months after application or if it was less time-consuming to apply. I suspect the Lee Valley product is Qualasol with a Lee Valley label, the instructions say it may be thinned with lacquer thinner so it's definitely a padding lacquer.
Thanks Deb. I've been gearing myself up to French Polish a solid body, but maybe I'll try this first.
Read up in the Library where we've discussed the application of Qualasol, my experience is that you have to apply it all in one session. You'll want to practice a bit before you take a pad to your guitar.
Pad varnishing can be a solution with cellulose based varnishes too, but it is of much less frequent use than shellac. In that case you should replace 95% alcohol by pure naphta or what cabinet makers call an "egalizer" (naphta based). Is is less convenient and the result is not superior to the usual FP, except maybe in wear resistance. It is called this side of the Atlantic "Florentine varnish". I used it once, but naphta stinks, and is dangerous. Is Qualasol a cellulose based varnish?
Ethyl cellulose is said to be the most common resin added to harden up padding lacquer, but (and my memory is shakey here), I believe Qualasol uses some other resin.
Thank everyone.. I've read the Milburn article and I was just wondering.. Since I'm using Alder.. I don't really need to bother with the Pumice, yeah?
You do not need to fill the grain on any closed-grain wood like alder.
I suspect the Lee Valley product is Qualasol with a Lee Valley label.
Deb, you are probably right. The Lee Valley Shellac and Lacquer Thinner (Shellac Solvent) has their own label glued overtop of the original 'Behkol' label.
I am about to French Polish my first violin, I've read everything I can
find on FP but it all seems to be about guitars. How do I go about getting a violin color when French Polishing?
Hi Thomas, I suspect you might get better responses by starting a new discussion. I've not built a violin, but I can tell you that so called 'spirit varnish' is just shellac with some additives to harden and improve it. The library has a lot of info if you just search, maybe 'spirit varnish' or 'violin finish'. It looks pretty fascinating and something one could delve deeply into the mysteries of, or just keep it simple.
Quote "Steve Senseney" Don't spend more than 30 minutes at a session...
Is this per surface Steve? I just finished my first guitar body by french polish technique and I found that it took me about 2 hours to do the whole body, one full session; bodying twice per surface, stiffing than spiriting off after each surface was totally done. If you can do the whole body, one full session in 30 mins, I'd love to know your secret please :)
Shouldn't speak for him, but I think Steve was referring to working a given area (say a back) no more than 30 minutes at a sitting.
I've found that the amount of time you can spend on a given area is inversely proportional to the cut of your shellac.
The usual 2 # cut is fairly "thick", and takes longer for the alcohol to evaporate out through it. The longer you work an area the thicker this area of finish gets - blocking the alcohol that much more and taking still longer for it to flash off.
Using a very thin cut of shellac. say a 1/8th to 1/4 th # cut, (such as used by Marshall Brune' "the Younger"
This is less likely to build up a " jello like mass" to pull off and cause cratering, but still builds your finish up nearly as fast as the thicker cuts.
You can pretty much polish till your arm falls off without a soft buildup, because each layer is so thin it doesn't block the gassing off of the alcohol much, and so the layers harden much faster. Ridges, etc. also tend to be smaller and more likely to just work out, rather than having to be sanded level.
I've been much happier with my FP using the thinner cuts of shellac, and using 95% (Everclear) rather than 70% (denatured) alcohol. Alcohol evaporates very swiftly, alcohol and water (denatured) pretty slowly.
Denatured alcohol is 95% alcohol. 70% alcohol will not work.
Why was i thinking denatured was 70%? Is it rubbing alcohol I'm thinking of?
Yes.