Ive got a large amout of breakable stuff that needs to be put into roadcases. A lot of the stuff is odd shaped and needs a custom box. I can build the box, but I was wondering if anyone knew where to get the stiff foam to put in the box.
Any decent Upolsterer in your area should have access to all the foam you need. As for Cutting it I suggest the tried and true, Electric Knife, You know the turkey cutting kind, the one Dr Frankenfurter uses to carve the Meatloaf. they work great for foam and are a bit less toxic than hot knives.
Most road case manufacturers will sell sheets of the foam that they use. I like the black expanded "hard foam" better the extruded soft foam.
For cutting, I have heard of electric meat cutting knives in use, I like Grandpa's big old knife. Same knife that one might see on the Three Stooges during the episode where they get trapped on a ship with a spy who has microfilm in watermellons. Sharp as a rasor and cuts foam easily.
A coping saw down to a PVC and or miter box saw will also work to some extent - a question balancing the teeth per inch to the material cut and speed of cut.
For more refined work, I use a walpaper retractable snap blade knive that's using a thinner thickness of blade.
For most work however, I'm using a hole saw that's put in reverse direction to slit instead of rip it's way thru the foam. Hole saw in a drill - especially a Milwaukee right angle drill - kind of much shorter and closer to the work, easy for sculpting. Turn the speed up enough on a forstner bit and drill bit and you also get similar results to some extent. A table saw and band saw will also cut the hard foam sufficiently.
Also a belt sander and even palm sander will also refine your work well. 3M type "Foam Fast" is great stuff for gluing together layers or materials to the foam. A dremmel tool on low speed, or even a router on especially low speed will also carve foam well.
I despise pre-preforated foam such as what comes in most road cases. Too soft to cut easily or support heavy materials it's to be supporting. And the preferations come apart with use far too easily making for a case that while fast to construct. As long as what you are cutting for is as square - not rounded and as deep as the preforations go in not having shallow preforations it's fine, but for me at least in opinion, something that will fall apart and lack support with use. Really hard to make something perminant out of preforated foam - especially if attempting to store stuff that is not all the way as deep as the foam you are pulling away to make a hole. Gravity also plays a large factor on this foam, with time since there is no structure, it sags. This material on the other hand if glued sufficiently to solid materials or the case can be used for lighter items.
Something I'm not able to do at this point is the fabric gluing to the foam. Such fabric or even carpet like material faces the more rough edges of the foam as is vacuformed around the materials to be held. No idea on such a covering of foam, tried it with a silk material at one pint, didn't work out well. Would love to finish my rough cut and sanded foam edges with fabric.