wrote:
If you think you can cut arbitrary shaped holes in large sheet metal
boxes with a milling machine, you have skills I do not have.

Not planning on large sheets anyway. But thanks for your comments,
they're helping me abandon overly expensive possibilities.

If you think it's do-able, don't stop just because I said that I tried
it and it didn't work for me :-).

Working sheet metal in a mill or a drill press has caused some, um,
near-disasters in many amateur shops. Poor clamping resulting in
spinning sheets with sharp edges are the most common but I've
personally put one dent in a cement wall with some thick sheet in a
belt sander :-).

I'm thinking my best niche would be to custom mill boxes up to 2X2X1
with walls at least 1/4 inch thick, with top panel either 1/4 or 1/8
plate up to 2X2. That's plenty for QRP, subsystems, microcontroller
boxes, and some scientific apps.

For sizes that small I think you ought to price out some common
aluminum extrusions.

2"x2"x1" is really tiny for any experimenting. Not so bad for a small
already-known-quantity project with a tiny tiny circuit board. But too
small for most homebrew projects and it just barely accomodates a
connector or switch or two on each side. And at that size you're
smaller than most existing die-cast and miniboxes. Heck, you're smaller
than an altoids box :-).

Or maybe you mean 2feet x 2feet x 1 feet? Even then you might want to
see what standard size extrusions are around. Quarter inch walls will
make a box that large be pretty heavy (not as heavy as the solid
aluminum block that big though! By my calculation that'll be 700 pounds
of aluminum as a solid block...)

Take a look at some of your competition:


http://www.globalspec.com/FeaturedPr...ildABox/9443/0

I think you could one-up them by making a web tool for
design/spec/order submittal. Having a selection of common extrusions to
start with and then specifying the customizations (mostly holes!, maybe
something about end panels, heck in my wish list I'd put painting and
anodizing and lettering), punch in my credit card number, hit "order
now", and a couple days later the UPS guy brings a finished box. Seems
feasible and a step beyond "fax us your diagram and we'll send you a
quote". expresspcb.com and frontpanelexpress.com show that there is a
real market for this sort of stuff, both "professional" and "amateur"
customers buy from each.

The goal is not to be cheaper than the mass-producers are, but to offer
true value in customization and ease of specifying/ordering.

Tim.