Ball bearing relief printing baren

A ball bearing baren, around 101mm in diameter.
 

WARNING

Printing this is fiddly and the tolerances are very tight. The 3mm bearing needs to be captured between the two plates while protruding a bit, and not falling out.

I went through a lot of test prints before being happy with the results, and still required same manual cleanup afterward, and your results will be different depending on printer, tuning, materials, first layer squish etc.

Hardware

• 263x 3mm stainless steel ball bearings (amzn)
• 7x m3x8 flathead machine screws (amzn)
• 7x m3x6 threaded heat inserts (amzn)

Printing tips

• Print at 0.2mm layer height or lower
• Reduce or disable elephant foot compensation. This may be enough to cause the bearings to fall through.
• Adjust hole size/fit for the bottom plate using XY hole size compensation. Try printing the hole sizer part and using the sizes there as a starting point for the setting. Each hole is 0.05mm larger in diameter.
  Bearings should sit flush with the top of the baseplate, and should not be very tight, or require much pressure to install.
• Watch for over extrusion, and consider using small area flow compensation settings. Only one wall on top surfaces may also help here
• Increasing Z-seam gap, or enabling scarf joints may help with excess material in the small holes.

Scrape or sand the surface where the two parts meet for a good fit. Doesn't need to be perfect, but should be free of blobs and big bumps.

Assembly

1. Install threaded inserts into handle
2. Test assemble the top and bottom plate together with flathead screws before placing bearings.
   The parts are not circularly symmetrical. There as a notch on each piece on the outside edge that should line up.
3. Carefully place ball bearings into all holes except the screw holes (the center hole, and the hole closest to the post on the outside rim. This is best done on a plate with a lip, or on a cookie sheet.
4. Without moving the base full of bearings, place the handle part on top, using the notch on the outside for alignment. The posts and holes are there to help keep the parts aligned during assembly.
5. Keep parts squeezed together, turn over and install flathead screws.

Related projects

Ball bearing

• 7mm ball bearing baren by Paul @ This Designed That
• Ball baren (parametric) by pacaro
• Regular glass ball baren linocut by Charlie_Poppins - Uses 16mm glass marbles

Smooth Bottom

• Print Baren by Pete Prodoehl
• Baren for linocut printmaking by Ruben V.
• Small Block Printing Baren by Robert Masen
• Baren by ipedrazas

Textured Bottom

• Relief printing baren by Billiam