I use 80 grit bead blasting media. Start with 1-2 tablespoons per cup of uncooked plastic and adjust for desired sink rate from there. I don't bother with salt anymore.
Medium plastic is all I buy. I keep a bottle of softener and hardener on hand in case I want a little different action to the plastic. most of my crappie baits get a little softener and everything else I've done so far has been just straight medium.
Joel, great video. I hand dip tubes myself & i also inject my angling ai mold in the color i want the tails to be & then hand dip them again in what ever color i want the body to be. I too am a tube finatic. lol
The only other way I know of is to use a small metal tube to poke a hole through it, feed the strands through the tube, then pull the tube leaving the strands. Slow, but it worked for some hobby work I did several years ago.
Big ole carpet needle . Does just fine . Does not even have to have a sharp point . Just thread a partial tab threw the eye just enough to pull it through the body . Then put some scent oil on the rest to grease it up so you can move it into an even position .