Looks to me one step up from a hacksaw and drill-press.
Looks like 2" lengths of 1"x5/8" strap-iron, with 1 or 2 peg-sized holes and some screw-holes in each one. They seem to be set on a base cast with ridges to guide the strapiron, but some creative jiggery and a deft hand with the welder will do a one-off...six-off faster than setting up for casting.
You can set the straps and then drill, keep the holes aligned and pegs less-stressed.
Alternatively, hog it out of 1" aluminum, free-cutting brass, sturdy plastic or finest mahogany. $99 table saw or table-router. Set the blade up 3/4". Leave the fence in one place, use cardboard or veneer shims (popsicle sticks?) to shift the work over each pass. Cut the through-grooves, then set a stop, go in between and cut 2/3rd or 1/3 through to get the stagger.
The "free!" blade comes with most $99 contractor saws will chew non-hard Aluminum pretty well. They are usually carbide, though a bit coarse. A more-teeth replacement will cut a bit smoother but of course costs more. Hard brass is hard on tools, free-cutting brass (dollop of Lead in the mix) cuts pretty nice. Hard mahogany cuts well with sharp teeth, else it burns. In plastic the real problem is melting. I have some frightful expensive adulterated-plastic decking which cuts like wood (with an odd smell) but is so flexible I would not try to hold a pitch. A block of good acrylic may be stiff but it tends to go soft and turn into a tar-ball on the blade.
A dado blade will cut wider, do a slot in one pass. That may not be faster in metal- the $99 motor will already be working hard with a narrow blade. A wide blade is less passes but much slower per pass. Anyway wobble-dados are ugly and dangerous, and good dado heads are expensive.
Of course, start with a yard of cheap pine, get your technique down pat, before you hit the hard costly stuff.
That's a LOT of wasting-away, but a table saw or even a router chews better than a hobbyist CNC mill. Difference between a solidly mounted large motor, and some super-dremel pulled by large dot-printer motors. And it isn't like you need complicated curves-- all straight lines and stops. I'm not sure about Doug's but many simple CNC rigs won't do the top-cut and a side cut (except as another setup); the tool doesn't bend that way. (A ball-cutter might make a nock to guide your drill, but is a bad bit for the heavy hogging.)
There's some pretty sturdy casting compounds. Glue-up a pattern in pine or clay, take a mold, pour parts.
Topic: STEEEL GUITAR (Read 11898 times)