2691
General Mach Discussion / Re: newbie - help with solving backlash issues
« on: April 29, 2012, 09:27:00 AM »
You will have backlash no matter what you do. Yes minimize it with the adjustment but then try moving the axis along it's full
travel to check for binding. Don't know the quality of the screw thread you have. Trial and error as Hood said.
Also check the ends of the screw and as there should be some type of bearing and that should also be preloaded since you can get addtional backlash form it. Check the backlash periodicaly to see if has changed some as time goes by.
I will point out that without some type of torque measurement you don't know how much of the motor torque is being applied to just make the axis move. As an example, say 200 in oz motor, then with a tight adjustment the required torque to move the axis goes from 20 to 60 in oz, due to microstepping the actual holding torque is reduced to 100 in oz. In the end you have used up 160 in oz and that only leaves 40 in oz as some head room. Poor example but does put things into perspective.
RICH
travel to check for binding. Don't know the quality of the screw thread you have. Trial and error as Hood said.
Also check the ends of the screw and as there should be some type of bearing and that should also be preloaded since you can get addtional backlash form it. Check the backlash periodicaly to see if has changed some as time goes by.
I will point out that without some type of torque measurement you don't know how much of the motor torque is being applied to just make the axis move. As an example, say 200 in oz motor, then with a tight adjustment the required torque to move the axis goes from 20 to 60 in oz, due to microstepping the actual holding torque is reduced to 100 in oz. In the end you have used up 160 in oz and that only leaves 40 in oz as some head room. Poor example but does put things into perspective.
RICH