Denford Triac VMC w/ ATC conversion

[stallone]

So I was able to get a little time with the machine this last weekend, but not much. I started to test the backlash on the Triac but I think I was doing it wrong. I am too inexperienced!! However, I did notice the end of the leadscrew (I think it is that) with the pulley, it moves back and forth approximate 2 degrees before engaging. I am not sure if this tells me anything.

Pic below of the end of x-axis pulley.



I did have time to measure the position of the stepper pulley on the shafts for the new stepper. The new steppers for x and y are much larger than the originals, but they fit!



Thanks for your help,
--mike

[andy_con]

you can easily get rid of backlash on a triac by just tightening the tab nut on the end of the table. getting the right preload on the bearings can be pretty tricky.

ive gotten he backlash on my triac down to 0.02mm, which im pretty happy with.

[stallone]

Hi Andy,
Where would I find this tab nut?

you can easily get rid of backlash on a triac by just tightening the tab nut on the end of the table.

...and what steps would I take to adjust it correctly. ...without screwing things up!
Thanks,
--mike

[andy_con]

you remove the pulley to reveal the tab nut and tab washer.

fold down the tab washer leg which stops the tab nut from rotating, then you can tighten tab washer.

only way ive found to do it, is to tighten put back together and check back lash, if still there remove everything and tighten even more. back lash should be checked using a test dial indicator

you remove the pulley by undoing the grub screw located in between the teeth

[Chaz]

you remove the pulley to reveal the tab nut and tab washer.

fold down the tab washer leg which stops the tab nut from rotating, then you can tighten tab washer.

only way ive found to do it, is to tighten put back together and check back lash, if still there remove everything and tighten even more. back lash should be checked using a test dial indicator

you remove the pulley by undoing the grub screw located in between the teeth

Ye, that's what my poor PM was trying to explain.

[andy_con]

Anywhere where there are angular contract bearings requiredpreloaded and there are two in the end green part of the table

[stallone]

Thanks guys.

This is great. I understand it now. Basically, I am adjusting the ballscrew tighter by the tab nut and tab washer!