Pitfalls to disabling power cross feed on a 10F?

[cdhknives]

I keep looking at my gouged and rounded off lead screw and wishing I could replace it. I could easily do the machining on a stick of acme thread stock, except for the dang slot that drives the cross feed. I have tried the power cross feed, and it is neat, but other than making a special effort to try it out I have found it to be more trouble than it is worth. So if I make a new lead screw with no slot, I lose power cross feed. Are there any hidden pitfalls to doing this other than a useless knob in the middle of my saddle?

 

[pdentrem]

No. The lathe would simply be the same as the original 10D. Without a milling machine to cut the slot it does become an issue. If possible I would still keep the power crossfeed. Needed for facing, and parting for examples.

 

[markba633csi]

If it's just a matter of getting another leadscrew, they come up on Ebay fairly regularly. You may have to wait a while to get one with low wear.
Mark

 

[wa5cab]

As Pierre said, aside from the lead screw diameter being 3/4" instead of 5/8", without power cross feed your machine would be essentially the same as the equivalent (Timken or Babbit spindle bearings) 10D except with a horizontal countershaft. Or as the equivalent 12" except for countershaft and a few other detail bits.

However, I would recommend trying to find a good replacement lead screw. If your machine has a 54" bed, then the replacement has to be from another 54" machine. If your bed is shorter, then you can use anything that's the correct length or longer by cutting off and machining the right end. The lead screw will fit through the spindle but unless your bed is a 36" one, you will have to rig up an outboard bearing to keep the left end of the new lead screw from whipping around while you are machining the right end of it.

 

[pdentrem]

I know some have cut off the two ends and flipped the threaded section and reattached the ends. The really worn part is now at the tail stock end where it will likely never be used. Just a thought.

 

[pontiac428]

I may have a lead screw for a charitable price if it works for you. I'll post the specs after I get home this evening.

 

[cdhknives]

I know some have cut off the two ends and flipped the threaded section and reattached the ends. The really worn part is now at the tail stock end where it will likely never be used. Just a thought.

This has already been done on my lathe. Most of the really bad wear is out of the normal use area but there is still significant wear at the working end.

I really want to replace the worn half nuts (they like to catch half engaged...really bad for threading!) but just can't see doing that without also replacing the leadscrew in the condition it is in.

 

[pdentrem]

I would go ahead and replace the half nuts. They are cheap and available direct from Clausings. Even with a lot of wear on the leadscrew, most threading jobs are well under an inch and the error over that distance usually will not cause problems. Obviously on long threaded sections this is not acceptable.

 

[wa5cab]

My recommendation would be to just find a replacement lead screw in good condition. I have also heard people mention cutting of both ends and flipping the center part over. But doing that with sufficient accuracy is not a trivial operation to begin with. And if it has already been done once, you obviously can't do it again, or at least not and improve things,