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Sorry all just posted this in the tutorials section by mistake. I just finished my first build with french polish and it looks great but i'm dissapointed with how easily it scratches does anyone know if there is anything i can put on it to make it more durable would Qualasole work?Any advice would be appreciated.Thanks all Rob

Just finished FP will scratch very easily. As it ages, it will become harder. It will still scratch, but not as readily. Some folks say, and I don't know, that FP continues to harden for years. Also some forms of shellac dry harder than others. The very blond ones are the softest. The seedlac, one of the least refined versions is harder, but it also has much more color.

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Waddy

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Thanks for the reply Waddy i meant to say that i finished the guitar about 3 months ago and it still scratches easily,i knew french polish was delicate but expected it to be harder than it is by now, i've been trying to find someone who's used Qualasole as it is supposed to be harder than shellac and can be applied over it,thanks again Rob

Roby,
I haven't used it, but I just googled it and from the MSDS sheet, it looks like it is alcohol, shellac, with a small amount of linseed oil, and some trace chemicals. I would suspect it wouldn't be significantly different than home brew FP, but I'd be interested as well to hear from someone who has used it,
Mike

Gum Copal and Gum Sandrac are mentioned in most old recipes and the Milburn tutorial, I'd like to try them personally as I loved the process of French Polishing. My finish was satisfactorily hard I used Walnut as it's a drying oil and Colin S recommended it, I don't know if that made the difference, but it still isn't hard enough for hard users so I'm going to try a waterbased lacquer next.

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I learn more from my mistakes than my successes

Interesting point about the walnut oil John i used extra virgin olive oil.Has anyone tried Finneys modified french polish? they make two types Finpol special and Finpol extra hard i emailed them and they said i'd have to remove the original finish i don't want to do that if it can be helped that's why i'm looking at Qualasole but can't find anyone with any experiance with it.Thanks for the input all.Rob

Roby, I've used Walnut oil and olive oil back and forth, and currently prefer Olive oil.

I've use almost every type of shellac, super blonde, Kusmi seedlac, waxy orange that I've dewaxed, dewaxed amber, and dewaxed garnet.

My box of Behlen's waxy orange shellac flakes is over 50 years old, and works as well as any other flakes that I have.

I've mixed in different amounts of sandarac resin, up to maybe 20%.

If there is a hardness range in these resins, I cannot detect it.

I do know that after about a year, shellac seems very durable, but it will never be like nitro or poly.

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That's a real shame I loved the process of french polishing, and was really hoping by the addition of those gums that I might be able to get it to compete with modern finishes.

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David,

How is the Kusmi? I found it interesting and thought about ordering a batch. Do you have to go through complicated steps for dewaxing?

Thanks!

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I get my supplies from these folks, they are really focused on traditional finishing supplies:

http://www.woodfinishingenterprises.com/index.html

The Kusmi seedlac is easy to dewax, I use the "tea-filter" method, a piece of T-shirt material, put the amount of seeds (or any waxy shellac) in the center of the cloth and tie it up into a loose bag. Suspend it in a jar of Alcohol and leave for a day. You don't have to, but I swirl it a few times, I'm the nervous sort.

Remove the bag, don't squeeze it out. It may have a little wax (shellac looks cloudy) let it rest for a day and decant (pour off) the clear shellac, leaving as much wax at the bottom of the jar as you can. I am anal about shellac, I decant it several times between decanting (sharp shouldered) bottles, nothing is prettier than transparent shellac.

I would advocate sandarac added to the shellac in a 5 to 10% proportion. It smells good, doesn't cost much, and I think it adds something to the finished product. The word is that it is one of the hardest of the natural resins, so it can't hurt at a small proportion.

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<Shaking my head> it is always sad for me to hear some disappointed in the hardness of a French polish finish. The reason it makes me sad is that it tells me that the applicator jumped in with little research. Shellac does harden with age. you can if you want apply an other finish over shellac but you will need to take the glazed or polished sheen off first. Adding resins like sandarac do increase the durability of the film but by the same token add to the work required to recondition the film and that hits on one of the great attributes of a pure shellac French polish finish. As you add hardening resins to the cut you proportionally loose the ability to quickly and easily recondition the film. You may ask how you recondition the film. Simple answer is the same way you put it on in the first place. (Assuming you did a true French polish application. No jab intended at anyone but I have seen a lot of people clam a ragged on finish to be a French polished finish)

My personal belief is that a firm spirit-off after ever body session builds a more durable film. I know it eliminates the need to sand with abrasive papers to achieve a level film because you build level as you body. As both Collin and I have often said we never touch our French polish finish with any abrasive. I have my doubt that this plays a role in hardness or not but I can say I have better durability than many seem to have based on their complaints.

But all that aside it all boils down to knowing and understanding that the film you are building is built up of the resinous secretion of the lac beetle. Not a nitrocellulose or a synthetic polymer. You can not expect any natural resin solid to produce an equally durable film as Nitro a modern catalyzed solid. But by the same token (in general) the less plastic or pliable the solid the greater the dampening affect on the plates. So each has it own attributes and each has its own draw backs.

I agree with the builder above. I fp'd three guitars before I finally figured out how to do it correctly. Then I built a double neck, I live close to Galveston, Tx, in the summer its very humide, between 65 to 80 percent all the time and I do the fp in an out side work shop shedd. The large door stays open while fping and the temp is usually 85 to 95 F. Uncomfortable to say the least but, I get the best and hardest fp finishes, the guitar is hung inside out of the sun till the next fp session. I have three to four sessions a week. I know some do a guitar in a week, not me, I spend a month. Back to the double neck, I sometimes play it very hard with a pick and the finish has never yet shown a pick mark and I know I hit the finish plenty. I can press on the top with my finger nail and leave no mark, thats not just touching the finish, thats pressing into it. So the man complaining that his fp is not hard enough you need hotter conditions to get it good and hard. I use the very lightest shellac I can find and the very best grain alcohol I can buy. Put it in a jar and let the sun help disolve then filter twice just to be sure.
If you need more help ask!

Jyme,

What wood is the top of your double-neck guitar? Its hardness makes a big difference owing to the thinness of the FP film.

Pat

I've seen old FP'ed instruments whose finishes were very hard, but I'm talking 100 years old.

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hey sorry for the absolute novice question
im seeking to find a good tutorial from sealing to finish and everything used
im just after reading the above and was intrested in the f/p methods that
involved heat
I live in ireland so i cant use the elements

but that got me thinking about having the guitar in the hotpress / the dusty attic
for a while into a small room with heaters on ?
do you need air circulation for it to dry ?
i dont mind any discomforts in any methods suggested
as f/p seems cheaper and nicer now
than other finishes
id rather buy tools i really need
but would like to get the best stuff i can
thanks again everyone tomas

I french polished my first guitar and loved the process I followed the Milburn tutorial, see link, and with a lot of help and advice from Michael and Colin S I achieved a satisfactory result, as to the hardness and toughness of the finish well I very happy with it I confess I'm not a light handler and it's got some marks from a cleaning spray I used to use clean my guitars and at the moment I'm too lazy to add a few more layers. I must admit I'm not 100% satisfied with the tru-oil neck if there's a weak link in the chain that's it.



Michael if you do add those resins to harden the finish how, other than not using them in the first place how can the finish be repaired/reconditioned?

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I learn more from my mistakes than my successes

I use Liberon"s extra pale pre mixed FP most of the time any more (thatnks Collin for the tip) I do not add any extra resin and the Liberon's is just shellac and solvent mix I have never found any need to add resin but may use them. they are desoved in to the mix just as the shellac flakes are if you are making your own cuts


80% of the marrs yo will get on a FP'd finish can be repaired just by a light boddinig ssession flollowed by a brisk spiritting off and finally a glazing session just as you apply the original finish. this can be done forever, no matter how old the FP finish is. that is one of FP's greate attributes. It is forever easily repairable.

Kenny Hill has an excellent article on FP here:

hillguitar.blogspot.com

-Rene

The thinner the FP the better. I use Everclear, Shelac flakes and Acetone. Most guitars can be French Polished with the proper build in about four to six hours. I usually take one day to FP a guitar then wait a few days and do some final sessions, wait about a week and buff it out. If you can't apply 99% of the finish in one day then you are doing something wrong.