7. Cassette Buffer Assembly

Relevant for:

MMU3

Last updated 5 months ago

Difficulty

Moderate

Steps

Available languages

Step 1 Tools necessary for this chapter

⬢Please prepare tools for this chapter:

⬢1.5mm Allen key for possible nut alignment

⬢2.5mm Allen key for M3 screws

Step 2 Parts preparation

⬢For the following steps, please prepare:

⬢Buffer plate (6x)

⬢Printer holder (1x)

⬢Buffer-leg (1x)

⬢Segmenter (1x)

⬢M3x30 screws (6x)

⬢M3nS nuts (6x)

Step 3 Peeling the plates

⬢Peel the protective layers off the both sides of the buffer plates.

Step 4 Assembly (part 1)

⬢Insert the protruding parts of the Buffer leg into the marked openings in the Segmenter. Push it all the way in.

⬢Insert four M3nS nuts into the small marked openings in the Segmenter. Push them all the way in.

⬢Insert the remaining two M3nS nuts into the marked openings on the Printer holder. Push them all the way in.

Step 5 Assembly (part 2)

⬢Insert the first buffer plate into the marked bottom opening in the Segmenter. Push it all the way in so that the screw openings line up.

⬢Make sure the buffer leg and the cutout parts of the sheet are on opposite sides - as seen in the picture.

⬢Attach the printer holder to the marked position on the buffer sheet. For now, it should be pointed up. The sheet should attach to the bottommost opening in the printer holder.

⬢Orient the whole assembly so that the buffer sheet is standing up. Both the printer holder and the Leg should be on the ground.

Step 6 Assembly (part 3)

⬢Insert the remaining 5 buffer plates into the corresponding openings on the Segmenter and Printer holder.

⬢The whole assembly now should look like the one in the second picture.

Step 7 Assembly (part 4)

⬢Insert three M3x30 screws into the marked openings on the side of both the Segmenter and the Printer holder. Tighten them up.

If the screw doesn't go in, make sure all the holes align with the plates.

Do not overtighten the screw. Otherwise, the buffer plates might deform.

⬢Attach another two M3x30 screws into the openings on the other side of the Segmenter.

Step 8 Assembly (part 5)

⬢Insert the last M3x30 screw into the marked opening in the Printer-holder.

Note that some versions of the part may have the opening on the opposite side, but the assembly process remains the same.

Do not overtighten the screw. Otherwise, the buffer plates might deform.

⬢Push the screw into the assembly until it reaches the nut. Tighten it up.

Step 9 Parts preparation: Plate-holders

⬢For the following steps, please prepare:

⬢Plate-holder (5x)

Step 10 Assembly (part 6)

⬢Attach the plate holders to the plates in the marked positions.

Step 11 Buffer segment parts preparation

⬢For the following steps, please prepare:

⬢Buffer Segment (10x)

⬢Wheel (5x)

⬢Ball Bearing 693-2rs (5x)

⬢Shaft 2.9x8.5 (5x)

⬢M3n nut (15x)

⬢M3x6 screw (25x)

Step 12 Buffer cartridge INFO

There have been several versions of this part available, which might look slightly different. However, the assembly process remains the same.

⬢

The MMU3 for the MK4 printer necessitates the use of the most recent buffer cartridge design, Version B.

Version B has been introduced in April 2024.

The version B accommodates the slightly longer unload distance of the Nextruder. If you're adapting an older MMU3 unit to the MK4, it's necessary to reprint the plastic parts of the buffer cartridges to ensure proper compatibility.

Step 13 Segment assembly (part 1)

⬢

Insert the bearing into the center opening in the wheel.

⬢Make sure the bearing is inserted all the way in, until flush with the surface.

⬢Repeat for the remaining four wheels.

Step 14 Segment assembly (part 2)

⬢Insert three M3n nuts into the marked openings on the Segment and push them all the way in.

⬢Add the wheel into the center of the segment.

⬢Push the Shaft all the way through the middle of the bearing, until it engages into the segment below.

Step 15 Segment assembly (part 3)

⬢Cover the assembly with another Segment part. Push both parts together to make sure the center shaft engaged into the top segment too.

⬢Join both parts together using four M3x6 screws.

⬢Turn the assembly around.

⬢Add the fifth M3x6 screw from the other side.

⬢Assemble all the remaining segments, using the same technique.

Step 16 Collets: parts preparation

⬢For the following steps, please prepare:

⬢Collet (10x)

Step 17 Collet installation

⬢Insert one of the collets into the marked position on the cartridge.

Note, for an easier instalation, you might want to squish the small fins together while you insert the collet into the opening. Otherwise, one of the fins might spread outwards, resulting in a damaged collet.

⬢Insert another collet into the other opening.

⬢Install collets into the remaining four cartridges too.