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Has anyone used that "rock Hard" shellac with the plasticizers being offered at LMI? I want to rub my finish into my guitar, but straight shellac seems like it may not be protective enough.

Thoughts?

jim

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Mmmm....wood.

I don't really know what additives they put in their shellac, but it seems a bit expensive for no reason.

You can put additives yourself that will improve your shellac. These are some other kind of resins and gums that you can mix with your shellac. Each one have different effects. Here are some:

Sandarac: It's a resin that comes from an african cypress. Very popular in violin finishing. some recipes use more sandarac than shellac. It gives a very hard and transparent finish. Adding some with you shellac will harder it without affecting the color.

Elemi gum: It's a gum that will give flexibility to you finish and also helps for adhesion of the finish on the wood, and between coats.

Dammar gum: It's a gum that leaves a crystal finish. Transparent high gloss.

Benzoin resin: It's principally used in parfumery and incense, cause it's smells really, really good, but you can also add it to your shellac to give it a nice lustrous finish.

You can also add different drying oil to your finish, that will also helps for the application. Linseed oil, Walnut oil, Lavander oil.

Possibilities of mix are endless. It's all up to you. You can find informations on all these products on the internet or in some specialty stores.
Just for example, here a recipe i'm currently using for finishing a uke.

100g Cherry shellac
40g Sandarac
15g Elemi gum
15g Benzoin
few drops of walnut oil
1000ml of alcool

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Francis Richer, Montréal
Les Guitares F&M Guitars

Other rub on finish options I've tried....

Tru-Oil
Tung oil
Wipe on polyurethane

I like shellac because its easy to level and sand. Great color options too. But it is a fragile finish. I usually wipe on a couple coats of polyurethane after I'm happy with the shellac. Just for extra protection from scratches or solvents
Tru-oil is great stuff too. Its a slow finish to apply, but pretty fool-proof if you prepare the surface well. Its pretty tough stuff once fully cured (at least 2 weeks)

Thanks much! I will look into these things.

How does the addition of these compounds affect cure time? I know commercial violin varnish (e.g. LMI's , with sandarac and mastic gums) has a lengthy cure time.

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Mmmm....wood.

very interesting. In violin varnishes they also use lavender oil if I am not correct, and sometimes ash. If you look up violin varnish on google there is an astonishing amount of info on various methods used to make it too. I wonder if that LMI stuff has anything in common with some of those old formulas.

I also never thought about rubbing poly on top of shellac.. I wonder if you could put a coat of Minwax tung oil over shellac? I've been doing kind of the opposite, by using the tougher coat first and then shellac on top, to give it that fine finish feeling, with underlying strength. On one body I did nitro first, trying some flattener for the hell of it, but didn't like it, and so glossed it back up with french polishing, and liked the results so much I kept doing it. This time Japan woodworking was out of Nitro so I got this violin varnish to use instead. If I am not correct, the lac in lacquer is the same as the lac in shellac, coming from a bug (as we all know), and thus the two should be at least distantly compatible and related, with different solvent mediums used.
Using that violin varnish got me to researching about that subject, which opened up a whole new world. I never for instance knew that violin varnish's shrinking qualities supposedly add to both strength and sound by "tightening" everything up.

...still learning...

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

This is a semi hijack but I don't ever recall seeing the cure time on wipe on poly. I'm finishing one right now with the minwax wipe on poly. Recomended cure time?

This stuff kinda sounds like it's a spirit varnish....Mike

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Another day, another dollar.

If you start using sandarac in the mix, make sure you are not skipping the flexible resin, such as the elemi mentioned above. Another variant is mastic (which is expensive though). I finished a couple guitars where I added about 10% of sandarac and 10% of benzoin and after a couple months the finish started to check above the rosette and purfling. I also used walnut oil, which might not have been good, I don't know. When I was sanding to level it every few coats, I would actually see some witness lines.

I haven't tried it with mastic or elemi yet, and I won't try it on a guitar until I test it over a sample (for example inlay some rosette leftovers in a spruce plate) and wait for a few months.

But the really important thing imo is to use raw shellac, button or seed. It is very easy to filter the wax and dirt with a coffee paper. I am really convinced this stuff resists sweat and heat better than the regular dewaxed flakes.

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Build log

Here's a link to an old thread discussing this product:

viewtopic.php?f=10101&t=32818

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George :-)

If we only talked about stuff that has never been discussed on here there would never be no new post....Mike

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Another day, another dollar.

Mike,

I don't think George was suggesting that at all. He was just being courteous and providing a link to more information for those who might be interested..

Then again, I could be wrong :p

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Jim Hansen

No, Jim, you are correct. I apologize if it seemed I was trying to squelch this conversation. That was not my intent at all.

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George :-)

I am on guitar 3,4 and 5 (kinda 6 ) 1 and 2 were traditional French Polish then a friend suggested the Hard Shellac from LMI. I am on the finishing stages of the guitar. It looks incredible. The time lapse of hardening to fine sand and polish is weeks at a time. The results are beautiful.