I read someone’s method of getting the wax out of shellac and have a few questions about this. First one is – why is wax in the shellac in the first place? Second- why, other than additional cost, do the manufacturers leave the wax in?
The method in the other post recommended adding mineral spirits, shaking the mixture, putting it in a squeeze bottle (inverted) and letting the wax/mineral spirits mixture float to the top before collecting the de-waxed shellac. Has anyone tried cooling it so the wax could congeal, then strain it? Would this work?
“I cut this piece four times and it’s still too short.”
Replies
Highfigh,
Shellac is a natural product made from secretions of the lac beetle. The wax is a natural part of the secretions. Yes, it takes extra work to remove wax, hence shellac is available with wax and dewaxed at a higher price. Wax does not interfere with the normal use of shellac at all, so there is no reason to remove it, unless it is necessary to change adhesion properties of the shellac such as when another coat is applied over it.
Shellac is also naturally colored a deep orange/red. Bleaching and wax removal go hand in hand, so dewaxed shellac is also among the palest shades.
Cooling might help in dewaxing, but the other method I described, using a paint strainer allows the wax to coalesce at room temp. I imagine cooling it a bit would enhance the process.
Rich
I know where it comes from and have used it a few times so my question should have been more explicit. Also, if I'll only be using shellac, the wax shouldn't be an issue but should I stir/shake it so the wax is evenly distributed or let it settle out? I have a couple of books on finishing and neither says anything about wax removal. I tried the strainer and it did nothing, although it was pretty warm at the time. I think I'll stick it in the fridge and see if it makes a difference since the can is almost half gone and it was only a quart, anyway. I bought Zinnser Clear (blonde) instead of flakes and definitely found the recommendation that diluting to a 2 lb cut makes it easier to flow it on and not have it dry too fast. Have you found any cold temperature storage issues with shellac?
"I cut this piece four times and it's still too short."
As already said, wax is a natural component of shellac. Shellac containing its natural wax is easier to sand than dewaxed shellac and is not a watervapor resistant. Other than that, there is little other difference in waxed verses dewaxed.
However, the big difference is that oil based poly and any waterborne finish will not adhere well to wax containing shellac. That is the reason the label on poly varnish will caution about applying it over a shellac. Dewaxed shellac is also quite a bit more watervapor resistant than natural shellac.
The normal way to remove the wax is to just let it settle out. A thinner 2# cut will allow the wax to settle faster and more completely than the 3# cut. But, do not use mineral spirits. The solvent/thinner for shellac is alcohol and that is the only thing that should be used. As far as I know, cooling does not materially affect the time required to settle out. Also, Zinsser treats their shellac to give it a longer shelf life and this process tends to greatly slow or even stop the settling out of the wax. Finally, some claim that filtering it through a coffee filter will remove most of the wax. It's a very slow process. I don't think that a normal paint filter will remove any of the wax.
Dewaxed is more water vapor resistant? I would have thought it was the other way around but again, I haven't used shellac very much. I thought mineral spirits was an odd thing to mix in, but I do know it dissolves wax. The paint filters did almost nothing with the wax and I don't drink coffee, so I'll just use the sanding sealer under poly if I have to. I know that's de-waxed. I'll toss the can and get a new one so I don't have to worry about any problems.
"I cut this piece four times and it's still too short."
>> Dewaxed is more water vapor resistant?
Yup, wax is a very poor barrier to watervapor unless you apply a thick coat of a wax like paraffin.
>> I thought mineral spirits was an odd thing to mix in, but I do know it dissolves wax
Alcohol is at least as good a solvent for wax. After all, alcohol is what is used to dissolve the shellac flakes and their wax.
>> so I'll just use the sanding sealer under poly if I have to
If you are referring to Zinsser's SealCoat, then that is fine under poly varnish. If however, you are referring to a real sanding sealer then there is a caution for that. Lacquer based sanding sealer contains stearates which are also deterimental to the adhesion of poly varnishes.Howie.........
I guess I was thinking about waxes being similar in their water resistant properties withough considering their different origins, as in oil based vs animal based. I've never tried to dissolve paraffin or beeswax with alcohol but many solvents will affect a lot of things, some more than others.It was the Zinsser SealCoat that I was referring to. If I use lacquer, it'll be compatible throughout.
"I cut this piece four times and it's still too short."
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