Get some of the super smooth
Get some of the super smooth Bullseye shelf paper. Find a small plate or lid that you can use as a template to cut it to the right size. The rough edges are because the glass is grabbing the shelf paper (or the other way around, don’t know) so smoother paper helps!
To fire polish in the micro kiln just bring it up to a red/orange glow.
Take notes every time you use it. Note the color of the glow that you see in the vent hole, this tells me more than anything else.
I get best result if I step up the power, so 1 min at 25% power, then 40% for 1 min and so on. Trying to get a slow steady increase in temp. If you MUST peek under the lid do so before you take it out of the microwave to minimize loss of heat (it ruins things). Best to just leave it inside the microwave overnight to cool slowly, then look.
Hope that helps. I’ve been playing with my microwave kiln daily for six months and for what it does, I’m happy with results. It is still limited, but once I get a big kiln I’ll still use it to test things (that way I can do two things a day! Yay)