Is French Polish too fragile to be practical?

Hobo

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Is french polish too fragile to be a practical finish to use on an instrument? I recently finished french polishing the spruce top on my newly built baritone ukulele. I had it looking pretty good, so after a week to let it cure – I began playing it regularly.

It didn't take long before I noticed the the french polished top beginning to get dull and deteriorate where my arm made contact with the top while playing. I realize french polish is not meant to be a hard, protective finish... I didn't realize it is so touchy and fragile to make it nearly useless. Maybe it needs a lot longer to harden? Any thoughts?
 
All my uke's are FP never had that problem..beware of aftershave lotion and such containing achohol on hands..that will affect the finish.
 
I believe FP has plusses and minuses. On the plus side, most will argue the instrument can vibrate more freely and sound better. Certainly it is not as durable as most of today's finishes but having said that, I have a mandolin with FP that I have had for over 10 years and have never had a problem. Also, FP is much easier to repair if there is an issue. Personally, if I were a road warrior gigging all the time, I'd think strongly about the more durable finish, but with the way I use my instruments, it's not an issue.
 
I've heard of people with extra difficult sweat.

I'm one of those- the glasses on my face always deteriorate after a year or two on my face. Which is also the reason I polish my ukes with a microfiber cloth after and before playing.
 
One week is too short a time for FP to cure properly, which may be why you're having a problem. I let FP'd instruments cure for at least two weeks, and I warn players to be very careful at first as the finish takes a couple of months to harden completely.
 
Zuch is correct, one week of "hardening" isn't enough, although you can go ahead and use your uke, and spiff it up in the future.

Those who naysay FP as a durable finish have to look away from hundred-year-old instruments with a FP finish still doing its job.
 
It's already been covered. Some people will wear a French Polish finish in months, others hardly affect it after years. Adding a drying oil to the mix should (at least in theory) lessen the wear caused by some peoples sweat. There is also the mighty expensive Ubeaut hard Shellac that might also fair better under such circumstances, although I have no real life experience of that product.
One week is certainly far too early to be handling the instrument. Some makers wait a full month.
 
I French polished the guitar I made for Henry Kaiser to take to Antarctica several years back. It returned a bit battered, but fine. I used walnut oil in the mixture as per Eugene Clark. FP is an acquired taste in today's instrument market...
 
Thanks for the comments! I'll not worry about it then until I let it have more time to cure. I was able to buff out the affected area and I'll let it sit for awhile -- guess I rushed it.
 
Oh no, this is a French Polish thread, it is waaay to early to end it.

Tell me about Walnut oil "in the mix"?
I used to use Walnut oil as my lubricating oil, but now use Olive. I can't tell any diff.

I have mixed in Sandarac as a small percentage of my mix, but am currently laying off of it, as it seems to make it too hard, and chippy.
Straight up Kusmi Seedlac seems to be best for me.
 
Walnut oil is a drying oil, and as such, if you put it into shellac, you're actually turning the shellac into a spirit varnish. Eugene Clark advises loading as much walnut oil in as the mix will take, though I found that to be too much. Olive oil is great for a lubricant; walnut oil can both lubricate and become part of the finish. I believe there's a whole Clark treatise on his approach to FP in one of the old American Lutherie magazines.
 
Walnut oil is a drying oil, and as such, if you put it into shellac, you're actually turning the shellac into a spirit varnish. Eugene Clark advises loading as much walnut oil in as the mix will take, though I found that to be too much. Olive oil is great for a lubricant; walnut oil can both lubricate and become part of the finish. I believe there's a whole Clark treatise on his approach to FP in one of the old American Lutherie magazines.

So the Walnut oil is added to the mix of shellac and not added as drops of lubricant on the muneca? I tried looking up the Eugene Clark article without much luck, as the reprint doesn't seem to be available. Woodcraft has pure, filtered walnut oil on sale now for $9.99 for 16 oz. May need to get some of that.
 
<the reprint doesn't seem to be available. > from Hobo.

Once American Lutherie magazines are made into a Big Red Book the reprints are discontinued. The articles never were available online (with very few exceptions).
 
So the Walnut oil is added to the mix of shellac and not added as drops of lubricant on the muneca? I tried looking up the Eugene Clark article without much luck, as the reprint doesn't seem to be available. Woodcraft has pure, filtered walnut oil on sale now for $9.99 for 16 oz. May need to get some of that.


You can do either, add it to the Shellac or add it as drops to the pad. Either way it's going to mix. You need the good stuff, the one without an added preservative. You can test by smearing the oil onto glass and exposing it to the Sun/natural light. After 4 or 5 days it should be dry - or at least very tacky. Walnut is just one of a number of drying oils that can be used.
You aren't creating a Spirit Varnish. It's effectively a cross between Spirit and an oil Varnish. A hybrid. How much Oil you can get to go into the Spirit is small but it does have an effect on the finished film. It should resist solvents a little better and be a little more flexible. Too much oil and you might be in danger of creating witness lines.
The problem with referring to Shellac (or any spirit varnish), is that there are a huge number of variables. The different types of Shellac will all have differing properties. Start adding oils, plasticisers and other resins to that and the variables suddenly shoot up. It all becomes complex, with little hard evidence as to what influence each type of Shellac, oil or added resin has.
 
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