Waxy Shellac?
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2 August 2014 at 6:11 pm #59984
I’m slowly making the transition to shellac as stand-alone finish, but I noticed with some blonde shellac I recently mixed up that there seems to be some wax (or what I think is wax) settled out at the bottom. I used blonde shellac flakes, powder really, and some 94% ethanol.
So, can all you shellac masterminds tell me if that is indeed wax? And if so, should I just pour off the good shellac? I’ve just been shaking up the jar before I apply it, and I have a feeling I’m just shaking wax back into the mixture.
Or, do I just have too much alcohol in the mix, and the whitish gunk on the bottom is undissolved shellac? Oh, and my I keep my shop around 16 degrees Celcius.
Thanks for your thoughts.
Attachments:
You must be logged in to view attached files.I’m not a shellac expert but the chemist in me might have some insights…
Ethanol evaporates readily, also in low temp conditions (just a bit slower then). The jar might not be perfectly sealed so the vapor can escape.
Eventually there might be some point where there cannot dissolve any more shellac, so the solution becomes oversaturated and the shellac will come out of the solution.
To see if that is the case you could pour off the solution and add some clear alcohol too see if it dissolves.
Btw that can be denatured alcohol instead of food grade alcohol, most governments impose some serious taxes on that stuff…Also I can imagine the shellac was dissolved in more comfortable temperatures and most products dissolve easier at higher temperatures.
Diego
3 August 2014 at 6:36 pm #60047Diego,
Great idea about pouring the clear stuff off, then mixing in more ethanol to the gunky remains and see if it dissolves.
I’m quite sure the jar has a tight seal, since there’s been no noticeable change in volume for over a month and a half. And it’s food grade ethanol, with a correspondingly high price- I didn’t want to get an alcohol with any additive like methanol. I value my optic nerve a little too much since I’m an illustrator by trade! I actually had to travel to Quebec to buy it, since most provinces and territories in Canada will not sell pure ethanol to the general public.
Thanks for the input, and I’ll try it this afternoon.
4 August 2014 at 3:54 pm #60090So, just to give an update after doing what Diego suggested, I poured off the clear shellac from the murky bottom, then added more alcohol to the murky remains. After sitting overnight, it’s still not dissovled so I’m quite sure it’s wax. And I’ve kept the shop at almost 20 Celcius to see if that would affect it, and the same separation happened as before.
I never had this hetergeneous happenings before with amber shellac, so maybe it’s just the batch of blonde powder I got.
One more thing learnt…I think!
So it was wax then… I thought wax also dissolves in alcohol.
Anyway, I’d try to use some of the offpoured solution on a test piece first to see if it’s still the same…About the food grade alcohol : I’d bet you have a really expensive finish. I’d still like to point out that most clear denatured alcohol contains only small amounts of methanol and possibly some ether. Not enough for any serious threat unless you’re breathing in the vapor all day.
Anyway if you’ve dissolved the shellac yourself there is always some residue forming, which should be filtered off if I’m correctly informed. Shellac is a natural product, so it’s likely to contain various substances which all have a different solubility .
Another thought : do you have the same effect if you mix the shellac solution with water? Try it on a very small sample if you can…
Diego
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