I preferred plastic, but it quickly started looking like glass was going to be the cheapest way to go.

I had a backup plan. Recently while researching sculpting and mold-making techniques, I came across a pretty good tutorial on vacuum forming. Vacuum forming is used to suck hot plastic sheets down onto a shape, so that a thin clear plastic mold is created.

I didn't want to have to build a whole vacuum chamber, and I definitely didn't want to sacrifice our home oven to experimentation (RIP clothes dryer), but I thought this method would at least be worth exploring. I made a visit to TAP plastics on Auburn Blvd. and found their thinnest acrylic sheet.

Two 16" squares cost about $6 each and I was on my way to becoming master of my own domeing.

"I'll be back on Monday after I ruin these", I quipped as I turned to exit.

"Oh, here, practice on these", the guy at the counter offered, handing over three rectangles of scrap. Awesome! Maybe I could pull this off!

My plan was to heat up the sheets with a heat gun and have them melt into a bowl shape.

I grabbed a steel colandar and dropped the first sheet of plastic inside. I cranked up the heat gun and fired away.

Nothing happened.

I guess I've gotten used to PVC plastic melting in one minute. This took much longer, perhaps 5 minutes passed before the sheet started to droop into the bowl, folding like a won ton wrapper.

This was obviously not going to work. The plastic was bending, but not really stretching. I needed it to stretch into the bowl and stay tight against the surface of the bowl in a nice clean curve.

On my next try, I took a page from the vacuum forming tutorial: I made a jig.

I cut identical holes into two pieces of lumber and sandwiched a plastic sheet between them. I figured the only place the plastic could go was down, drooping into a nice smooth bubble.

I came back with the heat gun and it worked! I could make a little dome! Even under the gun for 10 minutes, or in the oven for 5, the plastic never got very pliant.

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