Wobbly lead screw gear

[veniceboo]

In going through my 618 trying to figure out the threading potential, my son noticed that the lead screw gear wobbles significantly. We've determined that the spacer, or collar, that the gear nests up against is a little wobbly. Without going into details we were unable to make a new collar and mount it in a way that fixed the issue. In short, the initial diameter of the lead screw nearest the head stock is wider than further in where it rests, making the wobble impossible to fix since we had to make the collar bore large enough to fit on the left end of the lead screw. Weird. Question: Is this gear wobble going to affect the lathe performance significantly? I'm watching it and it definitely makes noise but I can't tell if it's hurting performance.

 

[Ulma Doctor]

How much wobble are we talking about?
A few thousands is ok, but much more than that is questionable at best.

 

[veniceboo]

Very noticeable, so way more than a few thousandths. I located a new lead screw locally after a call to Clausing, so I'm trying to figure out if this is bad enough to go that route.

 

[markba633csi]

Don't buy a new leadscrew- find a good used one on Ebay and save some cash
Clausing used to refuse to sell to California directly due to some issue in the past- don't know if that's still the case

 

[benmychree]

Gear wobble would likely result in a "drunken" thread, making a good thread fit impossible.

 

[veniceboo]

Don't buy a new leadscrew- find a good used one on Ebay and save some cash
Clausing used to refuse to sell to California directly due to some issue in the past- don't know if that's still the case

I'm in the South Bay area of California and this place is in Torrance, maybe 2 miles away.

 

[wa5cab]

Therein lies the rub (determining the "goodness"). Few people understand how to do that and fewer still will do it. If the gear in question is the one on the left end of the shaft that the left end of the lead screw slips into, I would shim the bore of the gear. In this instance, paper will be satisfactory if you don't have any suitable shim stock.