Parametric Electronics Box +TPU Gasket

Parametric electronics box designed in OpenSCAD. You control only a few simple sliders; everything else is automatic (screw layout, lip fit, corner radii). Optional edge gasket adds a TPU sealing ring. A dedicated Print view lays the tub, lid and gasket side-by-side for instant slicing.

Quick start

1. Choose screw type: screw_type = 0 (M3), 1 (M4) or 2 (Custom).
2. Set box size & strength: box_w (width), wall_t (walls), lid_th (lid).
3. (Optional) Edge gasket: turn gasket_enable ON and set gasket_tpu_w (TPU ring width).
4. Switch ui_view_mode = 4 (Print) → parts appear side-by-side.
5. Export (STL/3MF) and slice. Print tub & lid in PLA/PETG, gasket in TPU.

Parameters explained (only the sliders you see)

Scale

• scale factor — global scale. Keep 1.0 (recommended).
• scale holes — if ON, holes and grooves scale too. Keep OFF for accurate screws and gasket.

Box size / strength

• box w — overall width (X). Length/height use safe defaults in the file.
• wall t — wall thickness; use multiples of 0.4 mm (2.4 mm is a good start).
• lid th — lid thickness; 3–4 mm is sturdy.

Screws

• screw type — 0=M3, 1=M4, 2=Custom.
  • M3/M4 presets auto-set shank/pilot/counterbore and boss size.
  • Custom uses the advanced values defined in the file.
• hole clearance — extra looseness for printed holes (adds to shank). Start at 0.30 mm.

Edge gasket (simple)

• gasket enable — ON cuts a neat groove on the lid and adds a TPU ring model.
• gasket tpu w — TPU ring width. The model auto-sizes groove width/height and ring height so the seal compresses ~10–20% when closed.
  • Rule of thumb: TPU width = groove width − 0.2 mm (already baked into the auto sizing).

View / layout

• ui view mode — 0=Assembled, 1=Exploded, 3=Detach, 4=Print (use this for export).
• bed gap — spacing between parts in Print view.

Printing tips

• Tub & lid (PLA/PETG): 0.20 mm layer, 3 perimeters, 5–6 top/bottom, 15–25% infill, no supports.
• Gasket (TPU 95A): 0.20 mm, 2–3 perimeters, 0% infill. Print the ring separately if you don’t multi-material print.

Assembly & fit

• Press the TPU ring into the lid groove; it sits near the outer edge.
• Cross-tighten screws (M3 or M4 as selected).
• Too tight? Increase hole clearance by +0.05–0.10 mm.
• The lid lip is permanently joined; no split line in prints.

Troubleshooting

• Screws don’t slide easily: raise hole clearance or ream lightly.
• Gasket too loose/tight: change gasket_tpu_w by ±0.1 mm.
• I need more screws on long edges: lower the internal screw_span_max value in the file (advanced).