Depron, extruded polystyrene, is lovely for model building. It is popular with remote controlled plane builders for its strength and lightness.
You can buy it locally at remote controlled plane hobby stores or online. One online resource is RC Foam.
The shop will now allow it to be cut on their CO2 lasers if the material is 9mm or thinner.
Anything thicker than 9mm (.354 inch) IS PROHIBITED and risks a flash fire.
Some parameters to get you started:
|60 watt||60 watt||45 watt||45 watt||Cut width*||60 watt||60 watt|
|thickness||to cut||to cut||to cut||to cut||to score||to score|
Cut width is the width to cut or slice out of each particular thickness of material so that they will fit together in a joint, like this.
You can score it and then curve it. One person suggested maybe even cover it with fiberglass for a very strong custom shape.
Kerf is … significant.
Angle of cut has a mind of its own. This is a 1-inch diameter circle out of 9mm Depron, tilted on its side to show that the cut is not straight but actually kinda squirrely.
For material that is 0.107 inches thick, cut a rectangle 0.075 inches wide to end up with a gap big enough to allow another piece of depron to interlock.
Kerf + 0.075 = 0.107