View Full Version : Shellac Use

11-27-2015, 06:53 AM
I'm approaching the point in my building where I will need to route/trim the top/back and rosette channel. I've searched through the archives and elsewhere, and it seems that shellac is recommended prior to routing to prevent tearout, and in the rosette channel to stop the ca glue getting sucked up by the wood. It has also been stated that shellac is compatible with most finishes, but will it have to be sanded away after routing, if the wood is to be dyed. Even if the wood isn't going to be dyed, would it show up under a finish.
Secondly, for convenience I've seen various tins of Shellac sanding sealer here in the UK, but none seem to indicate whether they are de-waxed or not. Opinions state only use if de-waxed. Has anyone any experience with these? Thanks , Mike.

Michael Smith
11-27-2015, 07:11 AM

Shellac does help prevent tear out but the only time you really need it to prevent CA staining is with softwood tops such as redwood, cedar, cypress and some spruce. It definitely will need to be sanded off if you are staining the wood. If you are not staining you will need to apply an even coat or sand it off the entire instrument before using another finish . I don't know which products are available in the the UK here in the US the sealer is dewaxed, that's what you want.

11-27-2015, 09:12 AM
Michael, thanks for the reply, I suppose I also should have asked if it is easy to sand off, i.e. does it penetrate the wood deeply or just sit on top? Mike

11-27-2015, 09:35 AM
It will be quite thin, and yes it will sand off easily.

While it doesn't prevent tear out, it does toughen the surface a bit and helps with getting a cleaner cut on some of the very softest of timbers.