So I bought a MAD Glassinator pot call on sale from Cabela's...first thing I noticed was the glass was very hard to call from vs a regular slate call...so my question is how rough do you need to sand it to get it to work?
If the call didn't come with a sanding stone. I suggest buying. The glass needs to roughed up fairly hard at first. You don't have to condition the whole call. Maybe half to start. Goodluck with it this year!
I always use a greenie scrub pad. I think scotch brite is the name brand of them I was in the military and we always called them greenies. Anyway it roughs up the glass calls fairly well and they really work well on slate. The best part is I've been using the same the 2" x 2" chunk for about 6 years now and haven't had to cut a new one.
I could never get scotch brite to rough up a glass surface enough for me.
A stone is the best way to go. Even the screen drywall sandpaper works well. You want to scuff it NOT sand it. Go in one direction. I will tear off a small pc, maybe half the width of the pot call, place my thumb on it and with a good steady pressure, push down and across the glass. Stop, pick it up and repeat until you get it conditioned to the point you want it.