Mechanical
Board outlines
Section titled “Board outlines”Measured from each board’s KiCad Edge.Cuts layer.
| Board | Outline |
|---|---|
rodeo-motherboard | 90 × 112 mm |
rodeo-pot-bank-4 | 20 × 100 mm |
rodeo-encoder-bank-4 | 20 × 100 mm |
rodeo-button-bank-4 | 20 × 75 mm |
rodeo-pot-1 | 25 × 25 mm |
rodeo-encoder-1 | 25 × 25 mm |
rodeo-audio-3.5mm | 60 × 30 mm |
rodeo-midi | 40 × 25 mm |
rodeo-power-usbc | 40 × 20 mm |
rodeo-power-barrel | 60 × 40 mm |
rodeo-power-switch | 30 × 20 mm |
The 25 mm grid
Section titled “The 25 mm grid”Knobs sit on 25 mm centres, which is what lets a pot bank and an encoder bank stand side by side on one panel with their shafts in line. Both bank boards are the same 20 × 100 mm outline for the same reason, and the two single boards are a 25 mm square — one cell of the same grid.
The two banks differ in one detail worth knowing before you drill: the pot bank’s shafts sit 1.53 mm further along the board than the encoder bank’s. Knob spacing is identical; the whole row is offset.
Buttons are the exception. The button bank puts its four switches on 12.5 mm centres, with an LED 7 mm to the side of each — a button does not need a knob’s clearance, and a row of four fits in 75 mm instead of 100.
Pots and encoders both present 15 mm of shaft above their mounting face, so knobs sit at the same height across a mixed panel.
How boards mount
Section titled “How boards mount”Satellites hang from the panel. The pots or encoders are through-hole on the top side and the board hangs on their bushings and nuts. Everything else on those boards is surface-mount on the underside, which also keeps assembly single-sided.
Two cases need a standoff as well:
- The single boards carry one bushing each, so an M2 standoff beside it stops the board turning when the nut goes on or the knob is forced past its stop. 10 mm for the pot, 6.5 mm for the encoder — the heights of their mounting faces.
- The button bank has no bushings at all, and pressing a button pushes the board away from the panel, so two M2 standoffs carry it. Their length goes with the switch height and the caps, which are not chosen yet.
Everything else sits on printed parts on the enclosure floor:
- a rear rail carrying the back panel and every rear-I/O daughterboard — power, audio jacks, MIDI;
- a motherboard frame, which can go anywhere on the floor.
Daughterboards mount on M3 × 8 mm standoffs. Details and the printable parts are
in hardware/mounting/README.md.