Bambu Studio projects for the P1S: every v3 part on 9 plates

print/3mf/sand-table-v3-P1S.3mf: every part oriented for printing, PLA case
parts and PETG moving parts, supports only on the arm motor bracket, stronger
walls on the hub, carriage and brackets, solid counterweight. Slices on all
9 plates: about 23.5 h, 760 g PLA + 165 g PETG.

print/3mf/sand-table-v3-P1S-options.3mf: 12.5 mm sand ring, M2 switch mount.

print/tools/make_3mf.py builds both from the STLs with the Bambu Studio
command line (flattened system presets, fixed-up per-filament settings).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

BUILD.md

@@ -97,6 +97,8 @@ Head notes:
 ## 3. Print the parts
 All files are in `print/v3/`. [`print/README.md`](print/README.md) has the details for each part.
 
+**Bambu Studio users:** `print/3mf/sand-table-v3-P1S.3mf` has every part on 9 plates, already oriented, with supports and settings. It takes about 23.5 hours and uses 760 g PLA plus 165 g PETG. Print plate 1, the fit tests, first.
+
 **Print the two fit tests first.** The bearing fits are tuned for a P1S:
 - `00-fit-test-608`: the pins should hold a 608 firmly, and a 608 should press into the pocket with a snug push. The parts use the 8.1 mm pin and the 22.2 mm pocket.
 - `00b-fit-test-6804`: a 6804 should press into the 32.2 mm pocket and onto the 20.1 mm stub with a firm push.