9 x 20 lathe feed prolom

[MetalPlane]

Where do you get parts for a JET 9X20 lathe? Are there salvage dealers for lathes?

 

[MetalPlane]

New to hobby machinist first post. I have a Harbor Freight Central Machinery 9 x 20 lathe. But I have trouble with the feed on the lathe. I have stripped the teeth of the 42 tooth worm gears. This is the gear that mates to the gear on the lead screw. Has anyone else had this problem.? Any suggestions on how to fix it so it does not happen a third time. Is there a way to make the lead screw more rigid in the apron?

Have you found a FIX?

 

[C-Bag]

What are some of the causes and fixes for a worm gear binding up on the 9X20 lathe carriage feed?

I hit a hard stop when I couldn't stop the feed and it hit my carriage stop. Worked for a while after, but now binds up and kicks out the gears driving the lead screw.

I would pull the carriage gear box and check the split nut. It’s a funky adjustment and it could have gotten out of adjustment, or be stripped. Mine was not adjusted correctly and worn because of that. Bought a new split nut from Grizzly. The 4000 is basically the same machine with some differences.

 

[savarin]

check out this complete post as I had those problems as well.

9x20 stuffup

I'm unsure if it was my fault or the machine. I had two aluminium flanges bolted together on the faceplate with spacers so I could turn the outside dia and bore the inside dia parallel with each other and both end up exactly the same. All was going well on slow auto feed - bore, disengage the...

www.hobby-machinist.com

 

[savarin]

I forgot to add:-
When you have the leadscrew removed go from one end to the other relieving ALL the sharp edges and corners from the from the keyway groove and also from ALL the edges of the thread, not much just enough so it no longer acts as a tap gutting threads every time it travels.
Your half nuts will thank you and so will the bushes in the worm.

 

[Diecutter]

Where do you get parts for a JET 9X20 lathe? Are there salvage dealers for lathes?

Last time I ordered parts (which was a while ago) for my BD-920N Jet lathe, the toll free number was 1-800-274-6848.

 

[MetalPlane]

Last time I ordered parts (which was a while ago) for my BD-920N Jet lathe, the toll free number was 1-800-274-6848.

Thanks! I found the same number buried in the front of my manual (circa 1994). It worked and was able to order all of the parts. Unfortunately the "4012" worm gear is on backorder until March. Seems it is a regular problem and replaced often. The teeth on my old one are worn down to razor-sharp and climbing over the sliding worm gear on the lead screw. It binds and kicks out the 120T change gear.

I have the plans if there are any hobbyist that would like to make a new one.

 

[MetalPlane]

Is it a plastic gear?
Mark

No, Cast Iron

 

[Little Dave]

I found my stripped feed screw at Grizzly Industrial. Part number P4000739- $30.00 Hope this helps everyone.
now I am looking for the worm gear frame. The one with the 3 taped mounting holes made from cast iron. Grizzly dose not list it.

 

[Tony Hallo]

I have damage the worm a couple times by engaging the feed while the carriage is locked, dumb mistake. To prevent this I made an interlock for the longitudinal feed and carriage lock. The carriage lock bolt was replaced with a cam operated mechanism and the lock plate works in the same manner as the half nut interlock.