Can any one suggest an easy way of getting 4" circles? I need to buildup a 1/8" thick 4" disc. The way I was planning to do it was make an octogon shape, scribe a cicle inside the shape, drill a hole for a machine screw pancake to fender washers, chuck it into a drill press and sand away. Is there an easier way? Also, I have to make four similar discs all different diameters creating steps and then sanding to a smooth inclined surface. I am looking for a good method of laminating the styrene and the best way the make my inclined stacked discs? Also when laminating all of these circles/discs how does one keep everything perfectly centered?
This is by far the easiest way to do it.
[link]http://store.quilting-warehouse.com/083472.html[/link]
Worth its weight in gold.
HTH!
Cheers,
Alex
But a plain old basic compass (remember Geometry class) with two pin points is cheaper and just as accurate. Swing your circle a few times dragging the pin through the sheet styrene. Then snap away the waste outside the circle. I’ve done this often with 40 thou Evergreen. Should work just as well for thicker material
I concur, and let us know how this project goes so we can all learn!
I will as soon as I figure these things out.
This sounds like more info for the Enterprise projects, check my last entry in that thread, I suggest the same tool mentioned above. It is infanatly useful in scratchbuilding.
I use an el-cheapo compass with the point and pencil… I took the pencil out and taped in an eyeglass screwdriver, and scribe with the point.
When I was scratch-building my blimp the bulkheads were large(some up to 8" in diameter) styrene circles cut out of .80 sheet styrene.I put a #1 exacto knife in an old compass and scribed the circle.Then I broke off the styrene over the edge of a coffee can.Worked well and clean-up was easy when I chucked the styrene circle in my drill and held it to a sanding block with 150 grit sandpaper. 
I found a relitively cheap circle cutter at “Jo-Ann’s Fabric” They sell craft supplies as well. You could probably find one from almost any craft store.
Best Regards,
Mark
I have to agree with cardshark_14! That Olfa circle cutter is great on building my 1/48 Saturn V!
Lee Anne
this is probably late but whatever. i picked up a compass at a craft store specificaly designed for cutting. it came w/ 3 blades. it only opens up to 3 in. (6 in diameter) with a little thought and jerry rigging you can make it any size. it has more than paid off for me. i think it was around$5.
HEY ! shipgirl , that,s a darned fine idea . I thought I was the only one to see modeling tools in a fabric store or department . thanks luv . tankerbuilder