E4P Encoder Transformation

[JChang]

I've noticed that many teams use sealed encoders with ball bearing supported input shafts (mostly Grayhill 63R and US Digital S4) [1][2][3][4][5][6]. But our team still have several E4P from AndyMark floating around.They break easily and require very specific/percise/careful mounting, so I've drawn up a part that transforms the E4P into a bearing supported shaft encoder to (hopefully) make use of the E4P sitting around.

In the attachments from left to right:

1. The assembled view
2. The cutaway view: Green = Shaft machined from 1/4'' Aluminum round stock, Pink = 250 id 375 od bearing (VexPRO 217-2788 will do), Turquoise = McMaster 97414A630 C-Clip (or the extra ones included in the Ball Shifter package), White = 3D Printed or Machined housing.
3. Comparison with S4-X-250-X-S-B (model from US Digital site) and Grayhill 63R (model from VexPRO ball shifter stp)
4. Transformed encoder mounted on the Ball Shifter (no need for the US Digital mounting kit)

Some questions to CD:

• Is this a good or terrible idea? Will it help at all?
• Was this done before by other teams?
• Will the threads print well on a 3D printer? Anyone have experience 3D printing nuts and bolts? The current thread is 1/2-32, the same as the Grayhill encoder. A simple change in variable value in the CAD file can turn it into some other pitch.

I will make some when I get a chance (which, unfortunately, would be after kickoff when school starts)

Any suggestion/criticism/feedback is greatly appreciated.

[magnets]

If this works, it would be awesome. I hate those e4p encoders with a passion, and buying new s4's for both the practice and competition bot isn't cheap.

As for 3D printing threads, I haven't had any luck printing a slightly smaller 7/16-14 thread on a 3d printer, but the printer wasn't great and I only tried it once. You may have better luck, especially if you have a fancy printer. It doesn't look like it would be too hard to make the threaded part out of a piece of aluminum on a lathe.