[AT] Sandblasting safety

[ROBBRUT at aol.com]

Dudley- here are the products I use/have used.

Each family is listed in order of "less to more" aggressive.

Please note that there are many other parameters which influence surface 
damage, such as : nozzle size, pressure at the nozzle, nozzle-to-surface 
inpingement angle, distance to surface, media particle size, dwell time, and flow rate 
(media-to-air ratio).

(1) Plastic Media (Thermoset) 
Type I         polyester 
Type II        urea formaldehyde 
Type III       melamine  

(2) Plastic Media (Thermoplastic) 
Type V      acrylic

(3) Plastic Media (Other)
Type VI and VII  Corn or wheat starch-derived media (don't bother with these, 
as they are hygrosscopic and harden up when wet then dried)
Type VIII   Nanocomposite (GREAT for extermely sensitive surfaces).

(4) Baking soda    not much to offer

(5) Metal and Mineral-based etc.
glass bead
Starblast
garnet
black beauty
aluminum oxide
steel

DON'T EVER USE SILICA SAND, and remember that the stuff you are blasting off 
your treasures my be even more toxic than silica, since chromated primers, 
lead, cadmium and other nasties abound, especially on older finishes.

Bruce Thompson