The sandblaster in action, frosting a test-strip of copper for one of Tetranitrate's secret projects.
Step 1: Materials
Sand got in my nose, between my teeth, ears, and despite the goggles, my eyes. When this was done, I looked sparkly from all the garnet sand dust on my face. Consider wearing a bandanna, especially if you have any respiratory issues. Actually, you really want to wear a respirator, to avoid silicosis. Use goggles if you have them. Swimming goggles (that seal over your eyes) or a snorkel might work best.
To construct the sandblaster, attach the hose to the air gun, and drop the other end into a bucket of garnet sand or other abrasive. Any even-sized abrasive should work - we grabbed this out of a pile of abrasive meant for the water jet.
Once everything is assembled, proceed to sandblast!
My jeans are indeed whiter.
Step 2: Making the Sandblaster
Find a bucket of sand for the hose to rest in. Find some good method to keep the hose submerged in sand, like duct-taping the hose to the side of the bucket so that it's always pointed downwards.
We just tipped the bucket so the sand was in a huge pile on one side, and stuck the hose into that. Even so, every now and then the hose stops sucking sand, which sucks.
Hook the gun up to any compressor hose.
Step 3: Sandblasting
Tetranitrate draws a smiley face (and subsequently, a frowny face) on his pants:
I sandblasted my jeans because I am struck by what a ripoff it is to pay $60 for sandblasted jeans.
The tshirt I sandblasted didn't change colors, but it felt thinner in that patch.
Later I sandblasted "DIY" onto the back of my left pant-leg. The intersection at the forks of the "Y" actually burnt/blasted through, giving it that rough, well-worn look. Want ripped jeans? Just sandblast them a little more.
Otherwise, metals are great, so is glass (especially glass - you can mask and sandblast wine glasses, or just give a frosty finish to anything you're working on.)
Industrially, sandblasting is used to evenly rough a surface before it is painted.
Also, don't do what I did! Take off your jeans if you want to sandblast them - my leg felt burnt for a few hours after blasting them.
(all the same, it was a blast - I didn't take them off because this was impromptu and I couldn't, y'know, take them off there in public and all..)