Out of the many 3D printed knife sharpeners out there, this is mine. It is mostly designed around what I already had on hand: a huge spherical bearing, some shafts, miscellaneus nuts and bolts.

Here a quick breakdown of the parts:

• 1 to 2

Adapters to reduce the diameter from the bearing size to the moving shaft. I am using a 8mm diameter shaft, the two versions only differ from the internal shape, one is smooth, the other is splined to offer less friction in case the movement is not smooth while using it;

• 3 to 4 + 13 & 17

Additional front support for long kitchen knives. I usually sharpen everything from small EDCs to long kitchen knives, so I wanted some sort of support underneath. The adjustment can be made with some M5 screws.

NOTE: File 3. has to be splitted into separate objects and requires to print 2 nut hodlers;

• 5 to 7

These 3 parts are taken from a very popular project (see below the REMIX TAB for proper credit to the OP) and work well enogh to be used. I only modified the shape to have captive M5 nuts.

NOTE: I had to import and modify the original file, Fusion360 made them larger. The correct size is the 10%, so import the .STL and print all these 3 at 10% scale;

• 8 to 12

Spherical bearing holders and related parts. The main difference between V1 and V2 is that I decided to add a captive nut and bolt lo lock the part when the height is set. The stop is enough to hold the position but does not prevent the bearing from rotating on the shaft if enogh friction is there. So I decided to add an additional positive lock. It is not required but might be preferable to have it. Everything here is M5 based hardware.

• 14

The base for the shaft. Mine is a 10mm stainless shaft I had lying around.

• 15 to 16

All the parts needed to hold my set of diamond stones. They are a cheap stone pack bought from amazon, probably they have a common shape and will adapt to other stones as well.

NOTE: One or more springs will be needed to be able to hold properly the stones on the moving shaft. I ended up using a combination of two light springs in my case;