Myself, I put on a coat of finish first thing to avoid stains from finger grease, bbq sauce, spilled coffee, etc. because I'm sometime not as fastidious as I could be. Or, as my wife puts it, I'm a slob. :D
That’s what I as thinking, a couple of thin coats just to protect the wood. I would hate to have a oily fingerprint that showed thru the finish. But on a Facebook page of CBG owners and builders they recommend to do your work then varnish. I’m going to varnish first. They also recommend using this varnish. What do you think?
I think the general thread is pretty good, seal things before they can get gummed up. Just a word about your chosen finish material - it isn't varnish. Shellac, if I remember grade 8 shop class correctly, will seal the wood all right but if you don't put a true varnish over it it will be sticky and turn white if it gets wet (sweat etc). Shellac is especially good at stopping pigment from knots etc. from bleeding through. And as the lable says it will also tint your work an amber colour. Hope my two cents (that's three cents Canadian money) is of some use.
I don't have any experience with shellac, I use a few coats of satin spray-on poly for everything, usually sprayed on thick then wiped off but I'm going for a functional beer-proof finish on my builds for now, not anything particularly beautiful. Someday when my building skill goes up I'll explore other finishes.
I'm sure we have some finishing experts here that can help you out though.
Shellac is used for French polishing which is a traditional finish coat for acoustic instruments.
Spar varnish is pretty heavy duty stuff. It's traditionally used on boats for ultimate weather protection. It will work, all right, but it will be somewhat heavy and definitely also tint your wood darker. There are other varnishes - Varathane and Minwax being two manufacturers - that are more intended for furniture. Some, including some spray on types will be virtually clear and not tint the color of your project.You might even try some of the water based varnishes these companies make. Cleanup is easy and brushes wash up with soap and water.
you could also try sanding sealer. it is sort of a thinned lacquer that will protect your graphics and seal the wood against dirty finger prints, and lets later stain/varnish/poly go on more evenly.
d'oh, Erasmo beat me too it, LOL
Looks great Paul.