Foot massage roller

UPDATE

I added a custom printable bearing. It has a 0.2mm tolerance so your printer needs to manage that in order to use it. The inside is serrated to better grip the roller. Outer tolerance is pretty much zero so it will be tight to insert. Use random seam when printing and add enough walls to make solid. I recommend a bit of silicone spray. I also added a center foot that can hold two rollers together for a dual roller. It has zero tolerance and is held in place with friction if you wish to separate them later. Side feet are recommended (but not absolutely necessary) to use with the connecting foot as otherwise the assembly will be slightly crooked on the floor.

I wasn't satisfied with the existing foot massager models so I created a new one. The rollers are printed flat for durability and the frame is assembled with nuts (cheaper than heat inserts) for easy disassembly so the rolls are easy to change if required. Depending on your print settings the spiked rolls might end up somewhat sharp so if you have delicate skin I would recommend socks. I included two kinds of rollers but you can of course easily make alternative ones. If using on hard floors I would recommend to either print the friction strips from TPU or cut out some rubber and glue it on the bottom. If you use printable bearings I recommend this one: https://www.printables.com/model/17916-printed-bearing-608-no-balls-no-assembly-print-in

Printing instructions

I printed the prototypes with ABS and PETG, 3 walls, 15% crosshatch infill, 0.2mm layer height and 0.4mm nozzle. PLA should work fine too. Increase the walls/infill if required. Supports are only needed for countersunk screw holes in the frame part or you can use the sacrificial layer option found in some slicers. The parts are made with 0.4mm tolerance so should be no problem for most modern printers.

 Required materials

• 6 x 608 bearing (printable ones are fine too)
• 4 x M4 nuts
• 4 x M4x12-25mm socket head cap screws

Printed parts

• 1 x base
• 2 x frame
• 6 x spiked roller half OR hemisphere roller half
• 6 x guide pin
• 2 x friction strip printed in TPU (if you don't have rubber)

Assembly instructions

Assembly is pretty straightforward. Just be sure to clean out the parts and possibly drill holes if you have loose threads from printing.

1. Insert guide pins into other half of the roller and glue together. I used regular superglue.
2. Insert nuts into slots in base and screw the other frame into the base. Insert bearings to frame.
3. Insert the rollers in the bearings and then place the other bearing on the top axle of the roller.
4. Insert the other 2 nuts if you haven't already done so. Guide the rollers with bearings to their holes and screw on the other piece of frame.

Done!

Glue the friction strips or better yet some rubber on the bottom if you intend to use on hard floors.