Harold and Scott,
Thanks for your replies. I lean toward Scott's answer that if one did
break, it might be more serious. The one gear has me fairly worried as
the teeth are so thin. It also makes a fair bit of noise, which is annoying.

Harold, you have reassured me as to wear on the other gears. I was
expecting replies like "at the slightest bit of wear you should replace
the whole gear train". I guess this comes from my delving into a Porsche
914 transmission and replacing some gears (twice actually, but we don't
need to go into THAT).

I do use the lathe for pleasure, not a lot of hours or huge loads. I'll
either replace just the one gear or add the spindle gear too. There is
detectable wear on the other two, but much less.

Thanks again,
Steve

Harold and Susan Vordos wrote:

"Scott S. Logan" wrote in message
...
snip-----

I respectfully disagree with Harold, that if they fail, they will not
do other damage. I've seen it happen in Logan Lathes, and the tooth
that gets kicked out CAN wedge into another gear damaging it and even
the shaft or stud upon which it is mounted.


No problem with the disagreement, for I, too, have reservations about my
comment, and I bow to your expertise as a manufacturer of lathes. My
experience comes from running them, and I've never experienced such a
failure.

My reservations come not only for the circumstance you described, but one
whereby the gear is not made of cast iron, but steel, and the tooth folds
over under load and wedges, much the same as you described. I shudder to
think of the consequences. I was thinking optimistically, if not
rationally.

My logic in this matter, based on many unknowns, is that the OP uses the
machine for pleasure, likely well under capacity, so it's not stressed much,
so it's unlikely to fail, and, given a little luck, should the cast iron (?)
gear fail, it would toss the tooth, not wedge it. That would be a decision
based on economics, and, with luck, would be a good one.

Yeah, I have heard of Murphy! I know him (or his law) quite well. g

Had I been armed with more information, such as the machine is used for
gain, and must be up and running, I'd have likely suggested the replacement
of the two gears, without giving any thought to anything less. It's really
hard to know the circumstances of some folks. Could be the kids need
shoes, the doctor bill remains unpaid for the last delivery, and the
cupboards are bare. In that case, the gamble may be a rational option.

Harold