Estimating plastic quantities for dome forming

[shobley]

I have a requirement to create 2 plastic hemispheres - 14" and 13" diameter.

I'm new to vacuum forming, although I've been happily CNC milling and laser cutting for some time.

My question is how much plastic (in X and Y) would be required to form the two hemisphere?

Low detail, so 1/16" thickness plastic would probably work OK?

I'll be making the "plugs" using CNC egg-crate process, filled with fine plaster.

All advice gratefully received.

Thanks,
Steve

[BFModel]

Steve,
Sheet size would be determined by vacuum forming machine frame size. the sheet will stretch & thin out thru-out your "hemisphere".
Most sample vacuum-forming machines have an adjustable frame, so I would think a few inches added to eack side of part edge would be fine. add to that some scrap for mistakes & then the amount of pieces you need.