I'm not sure what kind of jig everyone else uses for finishing their scales. Most of the ones I've seen, and the type I still occasionally use, is to temporarily glue a popsicle stick (or something similar) to the bottom of the scale and then have at it with the CA or whatever other finish while holding on to the popsicle stick.

I did a little experimenting and came up with a new jig. It's quite simple, really. Just lay the scales good and flat on the sticky side of some masking tape, and then tape that down to a rigid surface with some more tape. I use masking tape because I can leave the scales stuck on it for as long as I want without having to worry about all that sticky adhesive residue coming off with the scales.

The main reason I came up with this jig is mostly for scales with liners. When working with liners, it was inevitable that I'd always get some CA or tung oil on the inside of the liners. Not that it was a huge pain to clean it off, but why do work that I don't have too Since the scales lie flush on the tape, I can really slather on as much CA or tung oil as I want without having to worry about getting any on the inside of the liners. It's inevitable that capillary action will probably draw a little CA or what have you around the very edge, but in my experience, it's always been very little.

Ohh, in case you're wondering, the scales in the pic are brass lined brazilian rosewood finished with 3 coats of poly. tung oil sealer and then 6 or so of glossy poly. tung oil