Before B00: belt and hot-bed checks¶
Note · Batch B00 — Calibration & jigs
The Gen 2 kit (Prusa order 1787919456, on the shelf) goes in in two parts (ruling 2026-10-01). The heatbed expansion joints and the nozzle wiper are fitted now, before B00. The GT1.5 belts stay deferred to the INDX 8-tool conversion this winter (Prusa KB), so the whole 157.0 h run prints on the current Gen 1 GT2 belts. Then run the two checks — belt tuning was never formally closed, and the bed has only been proved flat at 60 °C, not at ASA temperature. They sit here, after Step B00.0, because the hot check opens a project on the presets B00.0 installs; they run before Step B00.8 and before any plate.
0. Fit the Gen 2 expansion joints and nozzle wiper (verify on bench)
- Prusa's Gen 2 upgrade guide: chapter 2 for the panels only, with the Nextruder left on. Skip chapter 3, Belts upgrade
- Chapter 4. Heatbed upgrade, all of it: expansion joints, heatbed spacer and aligner, nozzle wiper, panels back on
- Chapter 5: skip Belt tensioning and Changing the printer edition; run the Selftest
- Settings → Hardware → Expansion Joints Gen 2 on, → Nozzle Wiper on, GT1.5 Belts left off. Never pick Edition = CORE One+ Gen2: it also sets GT1.5 steps/mm, wrong for the GT2 belts still fitted
- The heatbed came off, so the closed ±0.1 mm bed is open again: repeat the six-point bed check and re-fit the Z-stop correction caps until it is back inside ±0.1 mm
1. Belt pluck check (verify on bench)
- Motors disabled, head parked front, X centred
- Pluck mid-belt with belt.connect.prusa3d.com or the Prusa app
- Upper belt ≈96 Hz (≤98 Hz), lower belt ≈92 Hz (≥92 Hz), ≤8 Hz apart
- Out of range: Control → Calibrations & Tests → Belt Tuning (fw ≥ 6.8.1), tensioner screws half a turn, both evenly and alternately — left = upper, right = lower
2. Hot first-layer check, at ASA bed temperature (verify on bench)
- Step B00.0 done; Galaxy Black ASA loaded as in Step B00.1; the sheet glued and Adv. Filtration set as in Step B00.3
- File → Open Project:
slicer/checks/hot-first-layer.3mf— five 30×30×0.2 mm squares, four corners plus centre, one layer, on B00-P1's presets (bed 110 °C, the vendored cold start G-code); the printer box reads(modified). Slice (~5 min print after the chamber heat-up) and print it - No "bed not aligned" / Z-alignment prompt during the print
- Every square calipers 0.17–0.23 mm
- Spread across all five squares ≤ 0.05 mm
- Print it again from
slicer/checks/hot-first-layer-heat-off.3mf, the same plate on the heat-then-off start G-code: nozzle to 170 °C, retract, heater off, wipe, heater off again, then the mesh. Caliper its five squares the same way - Write down which start passed with the smaller spread and no prompt. If heat-then-off wins, stop here: all 22 plates must be re-synced to it and Live Adjust Z re-tuned before B00
Both pass → Step B00.8, and B00 prints on GT2. Belt check fails → retension and re-pluck. Hot check fails on both starts → back to the bed check in item 0, then re-run it.
- Firmware ≥ 6.8.1 (printer menu → Info) — required either way
The check's project is not a plate of the run and sits outside every total. python3 slicer/hot_check.py
rebuilds both projects from slicer/voron-coreone-asa.ini and slices them to prove one layer, five squares,
a 110 °C bed and the heater off before every probe tap; --check only re-slices the committed files. The
22 plates carry the cold start until the comparison above says otherwise.