TweetI've never used one... and never injected a piece of glass either (that I know of at least).

Probably not a bad idea tho. However, I'm sure it's going to increase waste as you'll loose some of your gear in the filter.

I think it you just stick to a smaller guage pin you'll be fine. I crushed some amps pretty good, and still didn't have any problems with a 23ga drawing pin. Clean breaks and a 25ga drawing pin should be pretty safe (although slow).