blasted finish/prep for parkerizing

[Justin King]

I built a sand/bead blasting cabinet this weekend and am hoping for some advice on media types and grits now that I can re-use it instead of blowing it out into the yard. I will be using it mostly to prep blades for Parkerizing so my concern is with the finish rather than performance in removing paint, rust, etc.
I have been using 20 grit sand and the finish is a little rougher than I would like, it acts almost like a file against the inside of a Kydex sheath. Will glass beads give a surface that will work for Parkerizing or does it need to be rougher? Or should I be looking for a finer grit alum.oxide media?

 

[b4thewheel]

As a hobbyist gunsmith, and parkerizing a few military type firearms, I learned it's best to use aluminum ox instead of bead. Bead doesn't leave a rough enough surface for the park to work right in. I can't remember the grit I use in blast cabinet, but it's not all that course.

I too been thinking of parking some knives if I ever get set up to make them that is. Still gathering tools.

 

[Dick]

Glass Bead is sphere shape and not sharp enough to clean the the heated treated surface steel.
You need sharp abrasive like aluminum oxide or silicon cabide for this job.