Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: kenh on August 02, 2009, 08:21:35 AM

Title: Metal shaft for rotary position sensor?
Post by: kenh on August 02, 2009, 08:21:35 AM
The rotary position sensors from Murata and Bourns need a 4mm D shaft. I haven't been able to find anyone who sells D shafts that small that are plastic or metal.

Does anyone know of any sources for this size D shaft? I checked McMasterCarr and Small Parts to no avail and a a few google searches didn't turn up any good results.

Ideally, I'd like a shaft that went from a 4mm D to 0.79mm so I could use it with a Didel 0.3 module gear, but I'll take what I can get.

If I have to get this made does anyone know a place that might be able to make this cost effectively?

Thanks!
Title: Re: Metal shaft for rotary position sensor?
Post by: matt liao on August 11, 2009, 03:30:18 AM
You can Diy the D shaft, find a 4mm round shaft, then file it.
Title: Re: Metal shaft for rotary position sensor?
Post by: SmAsH on August 11, 2009, 04:03:28 AM
yeah, you can... but be careful to get it right.
Title: Re: Metal shaft for rotary position sensor?
Post by: Ro-Bot-X on August 11, 2009, 05:55:44 AM
Here is a getto method for drilling a centered hole in a shaft:
- use 2 wood boards to build an L shaped structure
- use 2 identical cordless drills, in one hold the shaft and in the other hold the drilling bit
- use the L shaped wood structure as a guide for the drills to keep them aligned, place them upside down facing each other, so the drilling bit is close to the shaft that needs to be drilled
-turn on both drills at the same time and slide the one that has the drilling bit towards the other one gently, but apply presure so the drilling bit starts to drill the hole, retract when hole is deep enough

Now not all drills allow this method, since some don't align properly on the L shape guide, but you can adapt this idea to your situation.

Good Luck!