A drop-in stop-gate for an 80 mm-bore NUGGS hamster-tube run. It is a short straight section carrying the genderless quarter-turn NUGGS port on each end, with a captive print-in-place shutter that slides across the bore to seal a run — so you can keep an animal off part of a tube network without taking anything apart — and retracts fully clear of the bore to reopen it. Human-operated by a pull-handle above the tube; the animal can't work it. It clicks into every other NUGGS module (straights, elbows, the bin bridge), because it inherits the NUGGS coupling standard unchanged.
How it works
The shutter is a flat plate riding on a continuous captive lip (built from the
print-in-place library's battleship-tuned, rattle-free clearances). Slide it in
and it covers the whole 80 mm bore; slide it out and it parks in an open-topped
pocket, leaving the bore continuous and smooth — no interior ledge or step for the
animal, which is a NUGGS welfare non-negotiable.
It prints as one piece, gate captive, in the pose below: tube vertical on its port tips, the shutter parked open over its support pedestal so it prints as a trivial 0.6 mm bridge onto solid material. Snap it closed after printing.
Print settings
- Print this first:
nuggs-shutter-valve-coupon.scad— a small fixture (100 × 46 × 9 mm, minutes to print) that reproduces the slide fit. Tune the gate until it slides freely but without rattling before committing to the full valve. SeeNOTES.md → Print this first. - Orientation: as modelled — tube vertical, standing on the bottom port's sector tips and the pedestal base. No support material needed; the 45° skirt and the pedestal carry the wide drawer.
- Material / nozzle: PLA or PETG, 0.4 mm nozzle. Wall 2.4 mm = 6 perimeters.
- Layer height: 0.2 mm (the 0.6 mm print gap under the gate is 3 layers).
- Supports: none.
- Bed: fits Bambu P2S (256 mm) and H2C; module footprint ≈ 114 × 195 mm.
- After printing: free the captive gate with a gentle slide, then work it closed/open a few times to seat the fit.
- Heads-up: it is a large, long print (the full-bore gate + its support pedestal). That is inherent to a full-bore sideways gate printed tube-up.
Parameters
Everything in the [The NUGGS standard] group is inherited from nuggs_cfg() and
should not be changed — altering a coupling number means it no longer mates with
other NUGGS modules. The tunable parameters:
| Parameter | Default | What it does |
|---|---|---|
door_fit | 0.0 mm | The one slide clearance you may tune (on the coupon), + = looser, −0.2…0.5. The rail clearances stay the library's — do not loosen them. |
gate_t | 3.0 mm | Shutter plate thickness. |
gate_over | 3.0 mm | How far the plate overreaches the bore edge, so it seals with margin. |
lead_in | 30 mm | Straight full-round shell behind each port (grip + port backing). |
detent_h | 0.4 mm | Detent bump height on the coupon (the valve's closed position sits over the open bore, so it has no deck for a detent; the housing walls bound travel and friction holds it — see NOTES §6). |
port_tol | 0.30 mm | NUGGS coupling clearance — owned by the standard; tuned on the base nuggs coupon, not here. |
open | 0 | Preview only: gate position, 0 = closed, 1 = open. The printable part always renders open. |
Render previews with ./scripts/render.sh nuggs-shutter-valve --previews; gate it
with ./scripts/gate.sh --slice nuggs-shutter-valve.