[MadMark]

When we got our 24x24 cnc at my old job ~15 yrs ago it was $2500. The mech guy put it together over the weekend and handed it over on Monday. By mid afternoon on Tuesday (the next day!), it had recouped its direct cost in labor saved on the first couple of batches of parts thru it. I had jobs queued and ready to go. It was like a flood after the dam breaking. Generating gcode from .DXF cad files was almost trivial. The design cycle dropped to as close to zero as possible in both clock time and costs. It let a three-man shop (mech guy, instruments guy, engineer guy) build out machines that sold for over $125k each.

CAD

Finished panel

All panels cnc machined

Motor and encoder bracket two layers of 1/8" black powdercoated alum stacked.

 

[MadMark]

Very nice schematic. Ours wasn't anywhere near that nice.
Our cutter head was a Porter-Cable 693 single speed router. This was designed as a wood cutter, but with slow feed and a single spur, solid carbide, 1/4" cutter, we could cut 6061 aluminum all day. We added a manually controlled lube/coolant mister to the rig and replaced the original plywood spoil board with hdpe.
No fancy electric zero, we just twisted the Z-axis knob until my eyeball said "close 'enuf". Once set, zero was retained as long as power and we always parked at 0,0,1. No limit switches anywhere. 100% motion sim with Mach3 at the desk before submission to cut. 1st run has baby sitter, unattended once validated. Never really crashed it, but occassionally thumped the stepper against the physical stop.
We were only doing thru cutting, so +-.040" on Z didn't really matter. It worked really well. We had the wiring gal able to load/cut/unload just by printing the build drawing at her station.

 

[MadMark]

Desktop CNC and 3D printer each on TV tables.

Laser is on 2x2 home made printer stand.