[300sniper]

i went through the manual on adjusting the z axis jib and am not sure if the manual is covering how to do it with the z axis brake. i can't get the z axis to move with the machine off but i know the jib is too loose.

does someone have the proper procedure for this?

thanks.

[keen]

Hi - I adjusted mine recently. I used a dial indicator that measured Z movement (say at the bottom of the head near the Z slide) using step movement up and then down note direction change 'lost' or non movement steps. On adjusting the gib - As the gib comes close to neat adjustment the friction ramps up and more steps are lost with direction change. I am in metric but converting I would say if you have say 0.0005" lost motion with a fairly 'loose' gib then don't tighten up the gib to produce more than 0.001" lost motion. - This is of course assuming your Z thrust bearings are adjusted correctly and your screw and ballnut were not set poorly at the factory - or worn. You should be able to manually 'rack" or twist the head to the left and right with a dial indicator measuring the movement near one end. Depending on how far out your indicator is mounted (this will magnify the movement) you should see mainly 'flex" only - movement that returns to the previous direction push position quite closely. a major permanent displacement means the gib is loose - (or not in even contact ) - with the Z slide.

[keithorr]

Is there a better term than "lost". The steps aren't lost, they just aren't apparent when the gibs are tight. Isn't this sticktion? Is that even a term?
I know what your mean, but I keep reading posts where someone is concerned with lost steps when it's not a failure of the motor to cog. Loose couplers, collets, fixtures, temp expansion, sticktion, routers made of plywood or hdpe...
I always assumed lost steps was between the driver impulse and the motor shaft output, not a catchall term for "somethings wrong".
Feedback appreciated.

[keen]

Is there a better term than "lost". The steps aren't lost, they just aren't apparent when the gibs are tight. Isn't this sticktion? Is that even a term?
I know what your mean, but I keep reading posts where someone is concerned with lost steps when it's not a failure of the motor to cog. Loose couplers, collets, fixtures, temp expansion, sticktion, routers made of plywood or hdpe...
I always assumed lost steps was between the driver impulse and the motor shaft output, not a catchall term for "somethings wrong".
Feedback appreciated.

Yes it is a confusing term. Perhaps 'lost jogging increment movement on reversal' would be better.

[philbur]

I think it would be best to contact Tormach regarding a correct procedure.

Phil

i went through the manual on adjusting the z axis jib and am not sure if the manual is covering how to do it with the z axis brake. i can't get the z axis to move with the machine off but i know the jib is too loose.

does someone have the proper procedure for this?

thanks.

[300sniper]

I think it would be best to contact Tormach regarding a correct procedure.

Phil

that is what i will do. i was hoping i was just missing it on their site and someone may have had a link.