Jet 1340 A - Changing The Automatic Feed Gear

[quillercam]

A few weeks ago I ask about a lathe here and based on feedback I bought it. After a good cleaning I realized that the automatic feed gear was missing off the end of its shaft! I was a little surprised, but happy that I found the reason why I could not get the auto feed to move. Threading seems to be fine. I have no idea when it was removed and since I bought the lathe as is I reckon it's my bag to fix at this point. I'm sure someone ran it into the head at some point and chewed up the gear. In any event I ordered and received a new gear and attempted to install it. The issue is I cannot get my fingers never mind my hands behind the apron to install the gear/key and screw in the blot/washer.

I supered glued the key to the gear and washer to the bolt so I wouldn't have to fuss with many little parts but I cannot even get the gear onto the shaft. I tried for quite a while with a long needle nose but I keep dropping the gear! I was thinking of removing the top of the carriage but again there are bolts and pins that concern me. If you have the Jet Part List GHB-1340A / BDB-1340A look on page 28 (32 in below link) the gear in question is #31 on the end of shaft D. If you look at the part book on page 34 (38 in below link) parts 11 and 8, the inside bolts will only come out a bit and then get restricted. My assumption is if I remove bolts 47 and 85 the top portion of the carriage will come off, but taper pin 84 is also a concern. Again, I'm assuming its more for alignment and if I get the bolts out I will be able to tip up on the top and it will come off...but I'm guessing here.

I have several photo that I can upload but I can't seem to figure out how, but if you take a look at the part manual you will figure you what I need to do. Here's a link to the manual: http://content.jettools.com/assets/manuals/321357A_man_EN.pdf

Thanks all

 

[Bob Korves]

I have a Kent KLS-1340A that is quite similar to your Jet lathe. All the Chinese and Taiwan 13x40 lathes I have seen are similar in design. The feed gear and the half nuts get NO lubrication from the apron. You must reach back there and oil or grease the half nuts and feed gear when you oil the lathe. If you do not, they will wear badly and die young. Spares of both came with my lathe -- I wonder why? Having the lead screw oiled will help a little for the half nuts, but the feed gear needs lubrication regularly. While you are back there, do the half nuts as well. I use a NLGI #1 grease like Lubriplate 630-AA.

Edit: Sorry, I did not answer your question on how to get back there to work on it. I have never had my apron or saddle off but either are removable, not necessarily easily, but possible. I think you would loosen the apron from the carriage, would also need to disconnect all three feed/threading/power screws from their end mountings, and then the apron should be free. Again, no personal experience.

 

[quillercam]

Thanks for the tip on oiling. I will make sure I do that going forward. I was really hoping I could pop the top off (so to speak). Perhaps a few others will chime in on this one. Cheers, Alan

 

[quillercam]

Update on changing the gear. I managed to pop the top off the carriage by trial and error. I removed the bolts in the top of the carriage and loosened the ones on the bottom (front and back Strip bolts). Once I got enough clearance I slightly lifted the top of the carriage up and slide it out of the way (by sliding it on the way toward the tailstock). Now I have more room to work at the rear of the apron. I tried to install the new gear on the shaft but there's a burr on one side that I will need to clean up first. hopefully a file will take care of it and I'll update as things and time allows.

 

[quillercam]

I got it in. It was trial and error but it was a good way of learning the ins and out of the carriage! I now have auto feed in both directions.