Lathe DRO

[EdK]

Is is normal for the cross slide to move a few thousands when you engage the power feed? I was using the DRO to cut the blank for the metric thread I was cutting and noticed that the cross slide would advance a few thousands whenever I engaged the power feed.

Ed

[f350ca]

No but I was having the same problem on my Colchester, blamed it on wear. Turned out the bolt that holds the nut for the feed screw on the cross slide had become loose. You could feed by hand with no movement but as soon as you engaged the longitudinal feed the cross slide would shift, guessing it was the instant acceleration.

[Mayhem]

I have noticed that on my lathe too. Again, being over 100 years old I put it down to wear. Mind you, it is an easy way to take a light finishing cut

[EdK]

(03-05-2013, 10:09 AM)f350ca Wrote: No but I was having the same problem on my Colchester, blamed it on wear. Turned out the bolt that holds the nut for the feed screw on the cross slide had become loose. You could feed by hand with no movement but as soon as you engaged the longitudinal feed the cross slide would shift, guessing it was the instant acceleration.

I'm suspecting something like that also. Time to tear down the cross slide and do some maintenance. I lost the use of the cross slide lock when I installed the DRO. It's there but it's blocked by the scale. I plan on relocating it to the headstock side so maybe it's time to do that as long as I have it torn apart for maintenance.

Thanks for the tip on the loose nut.

Ed

[f350ca]

Can you make the dro change by pushing and pulling on the cross slide?

[PixMan]

Which axis is the one that moves when you enfgage the feed? Are you saying that the cross slide moves in (or out) when you engage the longitudinal feed? Our old (1974) Victor 1640 doesn't do that. It will, however, move the cross slide a tiny bit if you switch the lever on the apron from feeding X to feeding in Z. The clutch to engage the feed does not ever nudge the non-engaged axis.

[EdK]

(03-05-2013, 03:15 PM)f350ca Wrote: Can you make the dro change by pushing and pulling on the cross slide?

I tried moving the cross slide by hand to see if I could feel any movement but did not have the DRO turned on at the time. I'll try it with it turned on and see what happens.

Ed

[EdK]

(03-05-2013, 05:57 PM)PixMan Wrote: Which axis is the one that moves when you engage the feed? Are you saying that the cross slide moves in (or out) when you engage the longitudinal feed? Our old (1974) Victor 1640 doesn't do that. It will, however, move the cross slide a tiny bit if you switch the lever on the apron from feeding X to feeding in Z. The clutch to engage the feed does not ever nudge the non-engaged axis.

Ken,

Yes, power feeding longitudinally it nudges the cross slide a few thousands when first engaged.

Ed

[EdK]

(03-05-2013, 06:27 PM)EdK Wrote:

(03-05-2013, 03:15 PM)f350ca Wrote: Can you make the dro change by pushing and pulling on the cross slide?

I tried moving the cross slide by hand to see if I could feel any movement but did not have the DRO turned on at the time. I'll try it with it turned on and see what happens.

Ed

OK, I paid more attention to what I was doing this time and the DRO does change by about 20-30 thousands when I push/pull on the cross slide. I could even feel it moving so something definitely needs to be tweaked.

Ed

[f350ca]

It might be as simple as the lead screw moving, should be an adjustment in the bearings to take up the slack.