5. Pulley sets

Lubrication

• F604ZZ (x20), 604ZZ (x10) bearings

• GT2 toothed idlers (x2)

Actions

Although the pulleys have been lubricated in the factory, for high speed printing it is still recommended to add a few drops of light oil before assembly and constantly maintain.

Front pulley sets

• Front pulley housing (2)

Struts

• Bolt m3 x 30 (2)

• Nut m3 (6)

Idler posts

• GT2 20T idler (1)

• Shoulder bolt 5 x 25 x m4 (2, in the shoulder bolts bag)

• Nylon standoff 9 x 5 x 3 (4, XY standoffs bag)

• Washer 4 x 9 x 0.8 (2)

• Nut m4 (2)

Actions

Assemble the pulley housing as shown in the picture.

You might need to force the opening of the housing a bit wider, by adjusting the nuts of the strut, before installing the idler and standoffs.

(Beta kits only) Please adjust the nuts of the struts to squeeze the pulley housing so the idler won't slip up and down but can still rotate. In the future kits, some washers 5 x 10 x 1.0 will be used to cancel out the gaps.

Exam

Idlers should rotate freely.

Left rear pulley set

• Rear pulley housing (1)

Struts

• Bolt m3 x 45 (1)

• Nut m3 (3)

Idlers

• F604zz bearing (6)

• 604zz bearing (3)

• Shoulder bolt 4 x 40 x m3 (3)

• Nylon standoff 7 x 4 x 16 (3)

• Nylon standoff 7 x 4 x 3 (3)

• Washer 4 x 9 x 0.8 (14, as bolt length reducers)

• Washer 3 x 8 x 0.8 (3)

• Nut m3 (3)

Belt tensioner bolt (can do it later in ch 8. XY plane)

• Bolt m4 x 12 (1)

• Nut m4 (2)

Actions

Assemble the strut first. Use the m3 nuts of the struts to adjust the rear pulley housing so the gap is 33mm.

Assemble the idler posts as shown in the illustration. Note that the belt tensioner is on the lower side of the pulley housing.

Exam

The idlers can rotate freely.

Right rear pulley set

Assemble the idlers as shown in the picture. Note that the belt tensioner is on the upper side of the pulley housing.

Left XY joiner

• Carbon fiber XY joiner plates

Structure locks

• Bolt m3 x 08 (3)

• Nut m3, square (3)

• Washer 3 x 8 x 0.8 (3)

• Loctite® Threadlocker Blue 242® (optional)

Printed X endstop finger (Only at the left joiner. STL here: DAB or non-DAB version)

• Bolt m3 x 10 (1)

• Nut m3, square (1)

• Washer 3 x 8 x 0.8 (1)

Idlers

• F604zz bearing (4)

• 604zz bearing (2)

• Shoulder bolts 4 x 35 x m3 (2)

• Nylon standoff 7 x 4 x 13 (2)

• Nut m3, nyloc (2)

• Washer 4 x 9 x 0.8 (8)

• Washer 3 x 8 x 0.8 (2)

Actions

As shown in the pictures, differentiate that:

• Face the flatter side of square nuts to the bearing surface.

• Face the more rounded side of washers to the 604zz stack.

• The vertical CF plates have 4mm latches and 3mm latches which match corresponding CF plates.

Don't tighten the bolts and nut too hard here. The joint of two CF plates might crack. The threads of the shoulder bolts are M3, but not M4.

The CF spacer for the MGN9 rail is not shown

Exams

Make sure pulleys are correctly placed in the left and right XY joiners. Pulleys should rotate freely.

Right XY joiner