Lathe Back Gear Question

[Greg Hudgins]

Hello all!
I am very new here (as of today). I am hoping to get a little help tracking down a back gear for my newly acquired lathe. I have a LAM-350B. It runs fine. Came with some tooling, two 3 jaw chucks (self centering) and one 4 jaw chuck. I changed the tool post over to a Shars quick change tool post.
I removed the back gear yesterday to get a better look at it for measurements. I did call Boston Gear, they may have something close, but the ID for the shaft mount is only 1", and I need 1.375".
I am adding a few pictures for your viewing pleasure.
Any help or information would be great.

Thanks.

Greg

 

[4GSR]

It looks like an Asian built lathe, according to the date on the tag, 1977, that's old. There's a good chance of matching the back gear up with another lathe out there. I would check with Grizzly or Jet first, they may be able to match up parts with one of theirs. The teeth on the gear are "helical" shaped teeth, they are not going to be easy to with conventional equipment. It will require a gear hobber to cut the teeth.

EDIT: Look up Lantaine Lathe and lantaine lathe parts, lots of hits.

Here's a YouTube video I found:

 

[Greg Hudgins]

4gsr,
Thank you for the reply.
I have been searching the net for some time now looking for any info. I have seen the video, the guy did a nice job. I had called Grizzly a wile back, talked to their parts person, he stated that with out a part number there was no way for him to look for the part. I am going to try a gear puller this weekend to try to get the gear off of the shaft. I will see how that goes. I will try Jet and see what they have to say.

Thanks again for the info.

 

[Kernbigo]

check the boston gear catalog

 

[Greg Hudgins]

Hello Kernbigo,
I have looked through Boston Gear's catalog "rotary drive products", I can find nothing with the bore size that I need. I am still looking though..
Thanks.

 

[DoogieB]

Jet also imported that exact same lathe as the Jet 1024P. I watched one come and go on CL in a few hours, so I did some research on it. I ended-up buying a different lathe, but it seems that information on that lathe is sparse and the repair parts are almost non-existent. Good luck!

 

[4GSR]

..... I am going to try a gear puller this weekend to try to get the gear off of the shaft. I will see how that goes. I will try Jet and see what they have to say.
Thanks again for the info.

You can't pull that gear off. you're going to find out that back gear is all one piece. The gear is cast iron.

Boston gear or any of the other gear companies out there are not going to have anything in a helical tooth for that would match what you have there without replacing the gears on the headstock spindle also. Being foreign made, it will be a Module pitch form, not standard for use here in the States.

 

[Greg Hudgins]

Hhmm, ok. I have sent a few pictures to a tech person with Boston Gear, he thought it looked like a pressed on gear. I thought it looked like a one piece..... I will NOT try to use a gear puller then .
I am at a little bit of a loss now as far as what to do...
Thank you again 4gsr, you saved me a lot of grief I am thinking.

 

[Greg Hudgins]

Ok, have another question, after surfing the net a little, I have come across a few people talking about installing a VFD to bypass the back gears. For what I have, is this something that could work? I am still looking into this at this time.
Thanks again.

 

[JimDawson]

Ok, have another question, after surfing the net a little, I have come across a few people talking about installing a VFD to bypass the back gears. For what I have, is this something that could work? I am still looking into this at this time.
Thanks again.

In general, a VFD is installed in the home shop to convert single phase power to 3 phase power for running 3 phase machines on single phase services.

One of the things that the back gear does is to increase the torque of the spindle by the back gear ratio. When using a VFD on a lathe the change gears or belts should be used for major speed changes, and then the VFD can be used to fine tune the spindle speed. You could use the VFD to slow the machine down to back gear speeds, but you would lose the torque that back gear provides.