Has anyone seen anything on stopping backlash with rack and pinion drives?
Has anyone seen anything on stopping backlash with rack and pinion drives?
Salty,
I have heard of manufacturers doing 3 things,
1- using a pinion gear split in half so you can preload the 2 halves in opposite directions.
2-Using a helical pinion & Rack.
3-Using 2 pinion gears and preloading them in different directions.
Check for machine design magazine online and browse around in there, lots of goodies in there.
thanks for that I will have to look around
Shopbots use a turnbuckle to pull the pinion into the rack. The pinion being direct mounted to the motor, mounted on a pivoting plate. Other people have used springs to do the same thing.
Gerry
UCCNC 2017 Screenset
http://www.thecncwoodworker.com/2017.html
Mach3 2010 Screenset
http://www.thecncwoodworker.com/2010.html
JointCAM - CNC Dovetails & Box Joints
http://www.g-forcecnc.com/jointcam.html
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
Gerry
I was thinking of eother spring loading the rack (possibly a hard way of doing things) or more probably I will try to spring load the stepper
But I do like the idea of a mounting plate and sring adjustment
Did you see the previous post like this?
http://cnczone.com/forums/showthread...ighlight=rosta
This Rosta item is a central pivot tensioner.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.
Al, I got a round dozen of those Rosta gizmos after seeing your earlier post on eBay for cheap. They seemed like they'd be handy for a lot of tensioning tasks. Haven't used them yet, but they are slick little boogers.
Best,
BW