Step 04.2 — Fix which assembly is A and which is B¶
Step 2 of 38 with a helper · Chapter 04 — A/B drive units and front idlers
Tap to enlarge
Parts:
- masking tape · consumable
- marker · tool
- caliper · tool
Do:
- Write the destination on every part:
a_drive_*rear right;b_drive_*rear left;front_idler_right_*+[a]_tensioner_rightfront right;front_idler_left_*+[a]_tensioner_leftfront left. - Positions are as seen standing in front of an upright printer.
- Caliper the lower idler frames:
front_idler_right_lower21.6 mm,front_idler_left_lower11.6 mm.
Check
Every part carries its destination in marker, and the taller of the two lower idler frames is the one labelled front right.
Helper Writes each destination in marker as you call it out, then reads the caliper on both lower frames.
What you're looking at
Manual p.63 shows the four positions; the pair renders tell the printed parts apart. A is the rear-right drive and B the rear-left, so the A idler is front-right and the B idler front-left. On the idlers the give-away is height, not handedness.
Tip
the upper frames are handed the other way: front_idler_right_upper is 12.0 mm, front_idler_left_upper 21.6 mm. Caliper those if the lower pair is ambiguous. The 10 mm lower-frame gap is the belt-plane split.
Caution
Rev D+ / LDO: the motor identity comes from the wiring guide, not the manual: A = rear right → HV-STEPPER-1, B = rear left → HV-STEPPER-0. Get this backwards and the machine moves diagonally on a straight-line jog. src
Source: Voron manual p.63 · LDO wiring guide (Rev D) · LDO Klipper config leviathan-printer-rev-d-sbv2.cfg · Video: Part 3 @1:18:02