Cutting Cardboard/Foamcore

I've had luck making successive cuts with an X-Acto and a straightedge or cutting it like drywall - cut through one side, turn the piece over and 'snap' it back on itself and make the second cut from the opposite side. As for curves, I use only brand new blades that can be manipulated through the length of the cut. Try not to 'saw' but pull the blade through the cut. New blades are a must, otherwise, the edge will get ragged. Hope this helps.
Frank Kranick

You might try here:

A jigsaw would work once you get some practice but Frank's advice of sharp knives is still going to be the best method for all sizes. hth
The Keeper (of too much crap!)

Cardboard and foamcore are best cut with a Stanley utility knife, using new blades and changing blades often, and a steel straight-edge. There are no power solutions to this problem that work cleanly, that I know of-- and I've been dealing with both for many years.
X-acto and other brands of #11 blades will dull far too quickly to be of use. Olfa and other types of blades that come in snap-off sections will work, though some leave a burr that works against you.
Using either corrugated cardboard or foamcore, my technique is to plan the cuts as they pertain to inside and outside corners. I plot each on a sheet and cut only half-way through, but on the reverse side. For outside corners, the board is then bent to open the cut and I remove material from either side so the bend can then be reversed, forming a clean, bent corner instead of a joint between two separate panels. Using this method, it is possible to form complex shapes that have only one true joint.
Scott snipped-for-privacy@AOL.com

So you're incorporating a bevel here, yes? Nice technique. Up to this point I thought your name meant Captain Circutboard; does it really mean Captain Cardboard? 8^) Cheers,
The Keeper (of too much crap!)

I don't know about cardboard, but if foamcore is anything like heavy foam, a bandsaw ought to work well. I made weapons for live roleplaying games out of (among others) heavy foam, and I found that the options were to either use smooth edged hand tools, or very powerfull powertools. A weak powertool either doesn't affect the foam, or leaves a jagged edge. The more powerfull tools (as in lots of speed on the business ends), while being a form of extreme overkill, gave perfectly smooth edges. Be carefull though, as a small slip will destroy whatever you're working on; these tools take no prisoners.
Rob

i have an artist friend who uses and electric carving knife. she keeps the blade sharp. good for foam, too.

art supply stores carry foam core and card stock cutters.
Craig
art supply stores carry foam core and card stock cutters.
Craig

1. A hand held electric meat carving knife. WalMart.
2. A hot wire cutter. Its easy to make your own with a simple 24Vac transformer and a foot switch that either turns ON or shuts OFF the current. ON/OFF will let you control the temperature without needing fancy circuitry. The cutter wire can be nichrome wire (hobby shop, scrap toaster element) or welding wire. I use welding wire.

Captain Cardboard, yes; Circuitboard, no.
It seems from the rest of the responses no one here knows what foamcore is, since they are all offering sculpting tools of some form or another as the solution.
Foamcore comes in varying thicknesses, starting at 1/8 of an inch, up to 1/2 inch. Typically, 3/16 is used as it is nearly 1/4 inch thick and is strong enough for most uses. The material looks like thick, white cardstock, but it is actually two sheets of sturdy cardstock with a 'foam core' between them. This foam has a styrene base as all sorts of chemicals and paints will eat into it, but it is rather spongy by nature, but not beaded.
Other materials in the same family (clad foam core) are Gatorboard and Artcore. Gatorboard is a very interesting material in that the outside surface is very similar to Masonite, but very thin. The core, in this case, is very different in that the foam is hard and brittle. Gatorboard is more expensive, but much more durable than Foamcore, which will show dents easily.
Artcore is identical to Foamcore except the outside cladding is styrene plastic, rather than heavy cardstock. This is the least durable of the 3, but you can glue it together with solvent type cements, though they have to be used sparingly as the plastic surface is rather thin.
Scott snipped-for-privacy@AOL.com

You are correct, sir. It cannot be sculpted, per se.
Also, though I am aware of the quality of cuts that can be made with sharp hand tools, I was interested in whether any power tools could speed up large projects, especially when it comes to cutting curves.
Remember, I'm asking about corrugated and non-corrugated cardboard as well.

In my experience, cutting soft, fiberous material with any kind of power tool will not produce clean cuts. I've used everything you can think of to cut foam core and all sorts of cardboards over the years, but only when I knew these materials would be covered with something else. If the material is going to be used as the final surface, sharp blades are the only way to go.
Scott snipped-for-privacy@AOL.com

One tool you might try. The circular pizza pie cutter. You might be able to get a sharper one at the fabrics shop which sells a similar circular knife for cutting fabrics.

Thanks for the clarification!
I've used the other two but not Artcore; I'll try some. Cheers,
The Keeper (of too much crap!)