Centreing Design
Centreing Design
(OP)
I am trying to centre a gear on a co-axial drive system. The gear fits onto a shaft Ø52mm outside and a Ø48mm bore. Right now, I am screwing the gear onto an M52X0.8 thread. I am wondering how accurate this is.
How accurately can a pair of machine shops, one of whom is a gear manufacturer, cut threads concentric with the reference diameter? How accurate will the final assembly be?
Has anybody inspected something like this?
JHG
How accurately can a pair of machine shops, one of whom is a gear manufacturer, cut threads concentric with the reference diameter? How accurate will the final assembly be?
Has anybody inspected something like this?
JHG





RE: Centreing Design
My question to you is why are you depending on a thread to drive a gear. Wouldn't a spline or a keyed shaft be easier to produce accurately? What type of a tolerance is allowed on this gear? A gear can be produced to almost any accuracy you desire but the cost will go up.
RE: Centreing Design
Thanks for the response.
The gear is fabricated to AGMA 8. My gear attachment has to work with a 2mm thick wall. It is an optical system with requirements to be small, but to have a large aperture. I am considering a press-fit, but I want to be able to take everything apart. I have designed a heavy duty wrench to assemble it. Right now, the gear is bronze, but I am considering stainless steel. There is no heat treatment.
The actual problem is that we are considering the use of a resolver instead of the optical encoder we have now. The resolver has very tight centreing requirements.
JHG
RE: Centreing Design