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View Full Version : Std shellac vs dewaxed under top coat finishes



Brian Runau
02-11-2023, 10:28 AM
I used standard shellac in error under a Waterlox finish and it did not like it, so I have a can in my finishing cabinet. I am staining some walnut and want to go over the water based dye with shellac as a next step. I plan to finish the piece with Arm-r-seal top coat. Any one know if I can use the standard shellac VS dewaxed under the Arm-r-seal? Thanks. Brian

Robert LaPlaca
02-11-2023, 11:31 AM
Brian, I think one is always safest to use dewaxed shellac as a barrier coat than the waxed, under any finish..

Brian Runau
02-11-2023, 12:31 PM
Brian, I think one is always safest to use dewaxed shellac as a barrier coat than the waxed, under any finish..

Thanks Robert. The only way to use up my waxed shellac if it is the only finish I use then? thanks Brian

Jim Becker
02-11-2023, 12:47 PM
Non-polyurethane products will likely adhere, but anything with polyurethane will potentially have adhesion issues. Most waterborne finishes will also balk a little at waxy shellac. Always do a test to be sure! It's also important to keep a shellac barrier coat as thin as possible, particularly when waterborne finishes will come next. Shellac that's on too heavy may cause cracking/crazing of the subsequent finishing products.

The best use for the existing waxy shellac is for decorative items as "the" finish, IMHO.

Curt Harms
02-12-2023, 10:22 AM
If your waxy shellac has been sitting for some time without being stirred, the wax is likely on the bottom of the can. What's left in the can is dewaxed shellac. You may be able to pour off or use a small container to remove the dewaxed shellac on top of the wax layer. I don't know how long shellac has to sit in order for the wax to settle out.

Brian Runau
02-12-2023, 12:44 PM
If your waxy shellac has been sitting for some time without being stirred, the wax is likely on the bottom of the can. What's left in the can is dewaxed shellac. You may be able to pour off or use a small container to remove the dewaxed shellac on top of the wax layer. I don't know how long shellac has to sit in order for the wax to settle out.

I will use it up on something utilitarian. Thanks brian