Project-box panel: design & fit notes

This original flat PETG panel fits an existing screw-mounted hobby enclosure when a stock panel’s size, openings or mounting pattern do not match. One panel per cart quantity; electronics, enclosure, screws, nuts and washers are separate. Stock panels, drilled sheet or laser-cut material can cost less when they suit the job.

Measure the old panel or receiving recess, its corner radius and existing screw centers in millimeters. Enter the finished outside size, leaving any recess clearance yourself. View from outside: the bottom-left bounding corner is the common origin, X goes right and Y goes up. Inside-view tracings need mirroring. Two to six screw centers can have any accepted measured pattern; the bore and largest head/washer diameter are shared.

One to six openings can be rounded rectangles, obrounds or circles. The five ordered lists pair width, height, X, Y and corner radius. A circle uses equal spans and half that diameter as the radius. Square nominal corners use radius zero. The total opening fit allowance adds once to width and height and half as a normal offset to the corner radius. It does not resize screw bores or the panel. The drawing and its tables show finished dimensions including allowance. The preview, STL and price all follow these same dimensions.

Openings use 96 tangent facets, enclosing the requested rounded outline; the exterior uses 24 arc segments per corner inside the measured outline. This keeps rounded cutouts from undersizing the requested aperture. These are nominal CAD dimensions; physical print and fit tests are pending and manufacturing tolerance remains unverified.

Measure the largest body, mounting flange, retaining nut or washer overhang beyond each opening on both faces. Enter at least the largest required overhang per side; one conservative value applies to every opening. Its dashed envelope must leave 1 mm to other connector envelopes, 2 mm to the outer panel edge and 1 mm to screw heads. Every screw keeps at least 3 mm of material around its bore, 2 mm around its head and 2 mm between neighboring heads. Rounded exterior corners are checked as well. Deeper enclosure, cable, circuit-board and hand clearances need your own check.

Trace the complete panel and all centers before ordering. Use sound existing screw bosses on a flat mounting face, pan-head screws and no countersinking or overtightening. Check the selected thickness against connector thread reach, washers and retaining nuts. There is no recessed locating lip, snap feature, engraved legend or circuit-board mount. This panel is for low-voltage indoor hobby controls only, without mains protection, shielding, sealing, electrical or fire ratings. It does not replace a required protective barrier. No named-device fit is promised by presets.

Print flat on a broad face, PETG at 100% infill and a 0.4 mm nozzle, with all openings vertical and no supports. The full width and height must fit the store’s 245 mm usable envelope within the Bambu A1’s 256 mm bed. The default 125 × 72 × 3 mm panel costs $16 before shipping and tax. Exact polygon material volume and surface area include every opening and screw bore. Checkout validates the dimensions and recalculates the price.

Read the original CAD builder and shared fit and pricing geometry. The design uses original geometric primitives; no competitor mesh or enclosure CAD was copied.