Official Luthiers Forum!

I'm sure it goes bad, but how does one know? Color, appearance, texture, smell?.....
And what are the consequences of using "Shellac Gone Bad"? i.e. it doesn't adhere well, it doesn't cure well, it doesn't shine up correctly....etc.
Thanks.
-j.j.Brown39010.7718055556

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Yes . I use flakes and make what I need. Once it is opened a few weeks it is not any good .
john

It doesn't dry well when it's too old.

Al

I heard that you should test your shellac before using, by placing a drop on a non-porous surface like a CD, etc. Let it dry overnight, and if it is not hard the next day, then the shellac is not good. I tried it once, but it took 24 hours to dry and get hard. If it takes 2 days to get hard, it may not be good for use.
Tracy

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Tracy
http://www.luthiersuppliers.com

I have some shellac flakes I bought almost three years ago. I keep them stored inside a plastic bag, which is stored inside a ziplock freezer bag, which is stored inside a tupperware container. I started noticing several months ago that some of the flakes wouldn't disolve all the way. They just turned into like a gel at the bottom of the jar. I have a jar of some of this that I mixed a few months ago, and the layer of gel has never gone into solution.

I continued to use it for a while, straining off the shellac that didn't go into solution, and it worked fine for french polishing. Only problem was, the cut was thinner than it should have been because of the shellac that didn't disolve. I hate to waste it, but I've since bought a new batch of flakes and am using it now.

My guess is that, despite the three layers of protection that I've provided the flakes, some H2O has crept in, and has been absorbed by them, and hence not all of it disolves into the alcohol anymore. Close as I can figure, at any rate.

Best,

Michael

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Live to Play, Play to Live

I had a 1/2 tub of shellac sitting around for a few years, when I started to use lac again a while back I just bought some fresh flakes. A few weeks back I put an MDF top on my workbench and decided to use up the old stuff to seal it.

However the flakes did not dissolve completely same as Michael explains above. A few weeks down the track and those jellied flakes still sit at the bottom of the jar....Hmm wonder what it would work like as a grass killer?

Cheers

Kim

Does shellac go bad? I had a batch that almost killed me for looking at his girlfriend!   


    I thought about toasting shellac to kind of color it, just as a experiment. Don't have a clue about what it would do, but, on a related note, I wonder if heating
shellac would drive out some of the moisture. If that is the problem!

    Considering how hydrophilic alcohol is, I find it hard to believe, that water could be the problem, but I've only worked with shellac a couple of times.

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

I don't think the problem is moisture either Billy, I suspect that maybe some chemical which allows the amalgamation of the shellac with alcohol gases off after a while. Sort of like the day after the day after you ate the beanz...it's just spent and exhausted so to speak

Cheers

Kim

[quote]Sort of like the day after the day after you ate the beanz...it's just spent and exhausted so to speak [/quote]

Man you live in Australia? My, "spent and exhaust" must of been worse than I thought if you, so to speak, "sensed the disturbance in the force" from there.

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

Onya Billy

Hince the reason I use Zinsser's Seal coat unless I need garnet or extra blond. 3 year shelf life