rack and pinion

[senor J.]

hello all. Does anybody know where You can order precision rack and pinion on- line? I'm not looking for super precision, something around .oo4 would be fine. I found some in the msc big book but I dont think it is precision stuff. It doesnt even say how accurate it is. Help would be appreciated.

PS what can one expect to pay for precision rack and pinion for about a 4 foot length?

[Al_The_Man]

See this forum post, Boston gear is good, if you want higher precision you can order online from QTC Sterling products, they make a good precision rack with matched machined ends.
Al

[senor J.]

have you ever used the boston gear rack? how precise is it? Im using it for wood working ( routing ) not machining but would still like around .004 acurracy

[HuFlungDung]

I wouldn't worry too much about the accuracy of the commercial rack, its likely quite uniform. Its more a matter of "how accurately can you mount it, and how good of a fit will you make with the pinion?" The control of backlash through all the driving components is where the problems will arise.

[ger21]

Originally Posted by senor J. have you ever used the boston gear rack? how precise is it? Im using it for wood working ( routing ) not machining but would still like around .004 acurracy

Download the catalog. It says +0.000 -0.002 for racks 3/4" wide and narrower.

[dgalaxy]

can you still run a rack system on a 5ft table or is this not recommeded

[Al_The_Man]

There are alot of commercial tables that run over 20 ft with rack, I have retrofitted a 100ft gas/plasma table with a 12 pitch rack ( see some earlier links for photos).
Al.

[dgalaxy]

thanks AL