scale spacer

i am satisfied with the "flatness" of the scales next to the blade - but due to some (probably normal) variation in the blade thickness i want to use some spacer material between the scales and the blade. i have "dimpled" the blade and scales in anticipation of some accraglas coming from brownell's. the thing is --now that i have decided to go with some type of spacer to get a better fit do i glue the spacer to the scale first and then in a later step to the blade? or spacer to blade and then scales last? or do it all at one time and glue the pins (i'm using 1/8" welding/brazing rod and it seems just fine) scales and spacer all at once and clean up after it all dries? thanks.

I would glue the spacer to the handle material first. Then install the scales in whatever way you want (pins, screws) like you always would.

Not real sure how you have variation in the thickness of the "tang" and still have it flat unless you have tapered the tang. Can you explain what you mean?

A single thickness of spacer on each side can be installed at time of handle assembly but if you are using multiple spacers consider gluing them up ahead of time into a sandwich and then handle assembly will go ahead as a single spacer assembly.

Sometimes I glue the multiple spacers directly to the handle material before cutting out the handle , less fuss and bother lining up holes.