Ch 01Checkpoint

Checkpoint 01

Checkpoint · Chapter 01 — Frame

What you should have now — Everything Chapter 01 leaves standing: the eight horizontals, the four B verticals and the two bed support extrusions. CAD frame is the 250 set (370 mm horizontals, 430 mm verticals). Yours is the 350 set - same joints, longer members.

• Reference surface re-checked with straightedge + feelers in five positions; worst gap no larger than the Step 00.10 figure
• 10 A, 4 B extrusions used; C ×2, D ×1, E ×1 bagged for Ch 05
• All extrusion end faces deburred and flat against the square
• 16 frame blind joints engaged and fully tightened, evenly
• Bottom square diagonals equal; top square diagonals equal and matching the bottom
• All four vertical faces: diagonals equal, corners 90°
• Frame sits on all four corners with no rock
• Every vertical's access holes face outward and take the straight 3 mm key face-on
• Two bed extrusions running front-to-back on the front and rear rails, corner brackets, M5 precision spacers (not shims), 90° to the rails; FRONT tape on one of the two faces their ends land on
• Bed extrusions 65 mm each side of the centreline, 130 mm clear gap, checked at both ends; all four M5×10 and four M5×16 bracket bolts tight
• Titanium backers still bagged and labelled for Ch 05
• Frame log table filled in

You built a square frame with both bed extrusions on the centreline. 5 gummy worms.

Common mistakes

• Tightening as you go. The frame must be assembled snug, squared, then torqued. Bolts taken to full torque corner by corner lock in whatever error was there at the time; the mallet cannot fix it afterwards.
• Verticals installed with the access holes facing inward. The two horizontals occupy the vertical's two inner faces, so the holes must face out. Caught late, this is a full corner disassembly — check it at Step 01.7 on the first corner and the rest follow.
• Building on a "flat enough" table. A surface with one corner a few tenths high becomes a twisted frame that reads square on every diagonal and still racks the gantry. Verify the surface (Step 00.10, re-checked at Step 01.1) or do not use it.
• Using an M5 washer where the kit supplies a precision spacer. The brass precision spacer is a controlled thickness, not a washer; the M5 shims in the manual are all replaced by it. Substituting a washer changes the stack height.
• Forcing a roll-in T-nut. LDO flags the tolerance explicitly. A forced T-nut galls the channel and the next one will not go in at all. Try another face or another nut.
• Fitting the titanium backers to frame extrusions. They are gantry parts and go on in Ch 05, on the face opposite the rail — putting a backer on the same face as an MGN12 makes bimetallic bowing worse, not better.

Next

Ch 02 — Z drives, Z idlers, Z rails and deck panel (manual p.22–51); gated on batches B00 + B01 + B02-P1 + B02-P3, all of which printed months before the kit and are sitting in bins 02-Z0 … 02-deck. Nothing waits (print plan §2).

← PreviousStep 01.22 — Record the frame log

Next →Ch 02 — before you start