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I hear dewaxed shellac is supposedly better in every way over waxed shellac. So what's the point in there even being waxed shellac? is it supposed to be cheaper? more colors? I only know from what's at the borg, and so far SealCoat (dewaxed) is cheaper than the waxed alternative, so i dont know why i would ever use anything else.
Enlighten me.
I don't know much about it but I think the name "wax" for the stuff one can remove from shellac is a misnomer. It naturally comes from the lax bug in this form and for some reason, this substance is removed from it.
I'd like to hear personal accounts of non-de-waxed shellac causing problems for folks in finishing. I've read accounts online that tell me otherwise that non-de-waxed shellac has done fine versus dewaxed shellac.
I dunno...just curious is all. Some things get passed around as lore when no one really knows why. We all end up repeating it as gospel when it may or may not be true. I'm certainly guilty of it. Just posing some food for thought here.
I've used waxed shellac under alkyd varnish with no problem. But the oil, alkyd, and wax in the shellac should be compatible.
Shellac is a natural product and contains "wax" when it comes from the bugs...quite literally. The "wax" is not an issue for regular alkyd or phenolic varnishes, for example. Anything containing polyurethane does have issue with it, however; poly doesn't even like to stick to itself which is why you need to lightly sand between coats when they sit beyond a certain time. Water bornes also don't like to lay down on waxy shellac. Hence, the recommendation to use de-waxed shellac under them. So I just use de-waxed shellac for everything where shellac is in play to keep things simple, avoid having two sets of brushes (you don't want to mix them since fresh shellac re-dissolves finish left in the brush and so forth. Other than the darkest/dirtiest of colors, you can get almost any variety of shellac flakes in de-waxed format.
The only dewaxed shellac that I generally use is blonde. Almost every other shellac I have has natural wax in it. I like the way the waxed shellac flows on and buffs out. And although shellac will disolve into previous coats it doesn't mobilize all the previous coats, so you can use a dewaxed shellac over waxed shellac as a sealer if you really want to top coat with poly or those funky, modern, waterborn coatings. Most of the time I like to start and finish with shellac on furniture projects so waxed shellac is just fine.
As I have previously stated in an other post you can
de-wax your shellac by letting it sit undisturbed in a jar
for a week or so until the wax settles to the bottom then decant it.
For you BLO fans you can make stand oil by filling a jar with
BLO and setting it on a window sill in the Sun until it thickens.
Loved by artists as a medium.
Bob
Bob, that works for waxy shellac mixed from flakes but may not be effective for pre-mixed waxy shellac due to the "shelf life extension" stuff they do to it.
Afterall the need for dewaxed shellac really only arises from the increased usage of polyurethane varnishes and waterborne finishes which won't adhere well to shellac with wax.
It is actually wax--and wax that has been removed from shellac has some commercial applications I believe. By the way, shellac first entered commerce because of the red dye that it contains.
On a stand along basis shellac which contains it's natural wax is not quite as clear, nor is it quite as water resistant as dewaxed shellac. But dewaxed shellac is more difficult to sand.
Most colors are available with and without wax, though some of the pale (Kusmi ?) shellacs have very little wax from the beginning. Some relatively unrefined forms such as seedlac are only available with wax.
By the way, blonde shellac is not the same as bleached shellac. Blonde has the dye removed by filtering through activated charcoal. But bleached wax is chemically treated -- dissolved in a alkali solution, bleached with a chlorine bleach, and then precipitated back into a solid form. Bleached shellac is not sold dry however since it has a shelf life of a matter of days, and must be mixed quickly with alcohol to give it a reasonable life.
Zinnser has published an article called "The Story of Shellac" that you can find on line that has lots of interesting info about shellac.
Afterall the need for dewaxed shellac really only arises from the increased usage of polyurethane varnishes and waterborne finishes which won't adhere well to shellac with wax in it.....
Steve said it well.
Decanting works for the premixed shellac as well. I had a pint of 3# cut Bullseye premixed. It was separated nicely and no problem to pour off. I was able to decant about 2/3 of a pint can without getting any wax in it.Quote:
Originally Posted by Jim Becker
HTH
Curt
Interesting, Curt. Others have reported that "settling" is less effective with pre-mixed. I'll have to try it sometime...
it's a "lac" bug, or "what's in a name?" I use the de-waxed all the time.
Bill
Steve referenced "The Story of Shellac." It's available from http://www.naturalhandyman.com/iip/a...r/shellac.html . I read it today on the plane, and found it absolutely compelling!