Kearny & Trecker 2CH Dancing Head Assembly Issue

[WakelessFoil]

We wanted to try our hand at boring on a vertical mill using one of our larger boring heads. Time after time, our results were unfavorable. Something unbeknownst to us at the time, was causing our spindle to become uncentered with the hole we were trying to bore. We have finally found our culprit.
We learned that the head assembly of the mill we were testing on (K&T 2CH) was shifting back and forth about .010" when cranking the head up and down. I tightened the single gib-screw on the head assembly to see if there was any improvement. It is now down to .003" of linear play.
Has anyone had experience with this problem on similar machines? How did you go about fixing it?
Does anyone have a copy of the manual for the 2CH? I see copies online but of course they want money for a digital copy of a machine tool manual from the 1950's.

Thanks,
Justin

 

[Cannonmn]

Hope u find the answer. I’m posting just to get notified of responses.

 

[Jim Christie]

It wasn't clear on the initial list at Vintage Machinery,

Kearney & Trecker Co. - Publication Reprints | VintageMachinery.org

but it would seem that this might be the operator's manual for your machine or close to it.

Kearney & Trecker Co. - Publication Reprints - Model CSM, CK and CH Plain, Universal & Vertical Mills - Manual | VintageMachinery.org

You can view the pdf on line with out having to download it
If you look down the long list you may find a parts or repair manual for yours too or one that would be similar enough to help you out.
Jim
P.S.
Looks like this might be it.

Kearney & Trecker Co. - Publication Reprints - Model 2CH Plain, Universal, Vertical Milling Machines - Parts Book | VintageMachinery.org

 

[Brandenberger]

http://vintagemachinery.org/pubs/2098/7023.pdf is probably a relevant parts manual. You mention tightening one gib screw. Fig 6 in the manual shows two gib screws (presumably one at bottom and one at top of gib).

 

[WakelessFoil]

http://vintagemachinery.org/pubs/2098/7023.pdf is probably a relevant parts manual. You mention tightening one gib screw. Fig 6 in the manual shows two gib screws (presumably one at bottom and one at top of gib).

I assume loosening the bottom gib-screw and tightening the top will allow the gib to further wedge itself into the ways? At least that is what I gather from the diagrams.

After attempting this the error is slightly better (.002") but the head is becoming more difficult to elevate manually. If I tighten it any more we may lose the ability to move the head all together without power.

 

[Brandenberger]

If it were mine, I would block up the head from the bottom, then remove the gib (remove tightening screw and push the gib up and out). Clean it, check it for wear and flatness. Flush out the gib area, lubricate then replace.

I’m guessing you’ll find something useful in doing this, either dirt or wear.

 

[WakelessFoil]

If it were mine, I would block up the head from the bottom, then remove the gib (remove tightening screw and push the gib up and out). Clean it, check it for wear and flatness. Flush out the gib area, lubricate then replace.

I’m guessing you’ll find something useful in doing this, either dirt or wear.

How would you recommend flushing out the gib area? Brake cleaner maybe?

 

[Brandenberger]

I would remove the gib and evaluate, likely I'd use something which isn't aggressive like WD40. Clean the gib. And see whether the gib is flat or badly worn. When reassembling, lubricate the gib liberally with the proper lubricant.

 

[WakelessFoil]

I removed the gib and cleaned it as well as the slot it lives in. Both were not extremely dirty or worn so I reassembled it with lube and tightened the gib down. As I tighten the gib more, the head elevation becomes more difficult to turn while the error becomes less pronounced. I have got it down to .0015" of play when changing feed directions on the head. Maybe I need to loosen some of the bolts on the forward gibs to allow the head to move easier, while tightening the side gib to take up the slack? I suspect some of these bolts need to be loose as some were when we obtained the machine.