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Murky/cloudy shellac
http://w-ww.luthiersforum.com/forum/viewtopic.php?f=10123&t=50831
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Author:  1984 [ Sat Jul 21, 2018 11:19 pm ]
Post subject:  Murky/cloudy shellac

I mixed up a batch of shellac flakes in ethanol, the stuff they use in hospitals to clean equipment with. Its 95% and only contains a tiny amount of propanol. I mixed it 1 part shellac 4 part alcohol. It did dissolve very quickly but it looks murky to me, like very polluted water, there also are some tiny particles in the mixture that i dont know what is - it must have come from the shellac flakes.

Could it be that my shellac flakes have gone bad? there might have been a tiny amount of water in the glass jar when i put the shellac in, maybe this has affected it somehow?

Author:  Jim Watts [ Sat Jul 21, 2018 11:38 pm ]
Post subject:  Re: Murky/cloudy shellac

It could be wax. Let the shellac set in a warm spot for a few days and see if if separates out. If it is waxy shellac, the wax will go to the bottom of the jar and the shellac will clarify at the top, then just filter out the wax using a coffee filter, cheese cloth or some such thing.

Author:  B. Howard [ Sun Jul 22, 2018 4:34 am ]
Post subject:  Re: Murky/cloudy shellac

Cloudy usually equals water contamination in shellac. If the alcohol was not dilute then the flakes were probably stale and had absorbed moisture.

Author:  Mark Fogleman [ Sun Jul 22, 2018 10:22 am ]
Post subject:  Re: Murky/cloudy shellac

I always filter my shellac through a paper coffee filter. Dirt and insect parts are still in there in the flakes. You could have contaminated it with extra water in the container or depending on how old the alcohol is, it could have absorbed water vapor from the air too. I would test it on a piece of scrap after letting it settle and decanting the clear. If it gets hard and brittle you're good. If it doesn't or takes a long time to get cured it's probably not good.

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