Denford Software & Machines

So in that case then, if you have to replace the ball nut it's better to replace the screw too as a set.

that's about the jist of it, good ballscrews come with the nuts fitted, or at least set for the screw.
You can remove a nut, but you'll need a former to slide it onto to stop the balls falling everywhere.

MMM, yeah I noticed the ball bearings as started to remove one nut, stopped before I lost only a few balls.

Sorted the motors out though, I dropped the amp to 2A and also lowered the micorsteps to 5/1( I assume the figure of 2.5/1 you gave related to the microsteps), 5/1 is obv the metric setting on the driver, wondered if an imperial setting be more acurate? the steps in mach reduced from 1000 to 500, plus the motors sound alot happier, I had managed 1200mm/m before it started losing steps in change of direction. But obv wont be running at that speed, 1000mm/m is where I wanted it. But still I had to slow down the acel in mach still to 5, even at a low speed the motors dont like the change in direction as is, may have to look at new motors in the future.

Thanks all for your help

The original setup was 1/2 steps (400 steps per revolution). The motor runs through a pulley which gives a 2.5:1 reduction, which drives the 5mm pitch ballscrew.
This should have given you around 2 m/min movement, with the drives running at 36 volt 2 amp.
There's no need to go any lower than 1/2 steps as this gives you pretty good resolution.

5 / 2.5 / 400 = 0.005mm per step

your steps per in Mach3 are 200 with this setup and I normally set the acceleration about 10% of the velocity.

Large519 wrote:MMM, yeah I noticed the ball bearings as started to remove one nut, stopped before I lost only a few balls.

Did you get the balls back in ?

I initially tried 200 steps, then 400 but the axis travel was out using a 50.8mm slip so when using the auto setup thats what they worked out at, and they were the same on all 3 axis, still managed to get within 0.02. My driver doesnt go any lower than 5/1 for metric, how does that work out for the imp settings?? Mybe the new drivers are to much for the old motors, will pos look to upgrade them too in the near future.

I lost 5 bearings, it doesnt seem to have affected the travel in anyway, and there was no play in the screw, I checked that before putting it all back together.

ok, lets get it setup correctly on 5 microsteps. If it's one fifth steps, then you're getting 1000 steps per revolution. Are you setting it up in metric or imperial ?

Setup is metric. Current steps in mach 500

So the steppers and pulleys and ballscrew are original. What do you get if you move the axis 100mm.

Yeah steppers, pulleys and ballscrew are all original.

I'll check the movement over the weekend and get back to you.

ok

Checked axis movement, moved 100mm and it measured 100mm.

Steps per setting must be correct.

sounds good