Jet 1236-ps Revisit

Gman45acp

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While cleaning up the lathe I got I noticed their is a hole where the lead screw enters the quick change gear box. It is threaded and it looks like there is a bushing between it and the lead screw. So does anyone know if there is a set screw that should be there and that set screw tightens on the lead screw on a flat or hole in the lead screw. The lead screw has to be held somehow to the gear box shaft.
Thanks for looking
 
If you can post a picture it would help to better understand exactly what you are describing. Then I’ll take a look on my 1024P and see if I can get you an answer.
 
I can move the lead screw and line up the hole. There appears to be a bushing see yellow arrow but does not show a bushing in the manual. Also does anyone know the size off the motor Pully. Manual shows it is a two step Pully but does not show whar the two diameters are
 

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There should be a pin that goes through the coupling and lead screw. You can see the same thing on the feed rod. They're meant to shear if you were to accidentally run the carriage into a steady rest or the headstock before getting the feed or half nut disengaged.
 
That’s what I thought but then why is the hole threaded and there is no hole 180 from it. If the pin sheared how would you drive the broken piece out?
 
That's odd. I don't have your machine, but I do have a Jet 1340 and the manual shows a pin, which is what I've always encountered on other lathes I've worked on. Your manual doesn't show what is used?
You said you can move the lead screw to line up the hole. Are you saying there's a hole in/through the lead screw?
 
Looks like a sheer pin or set screw should go in there to me. Does the leadscrew rotate at the same rate as the collar? There may just be gunk built up that keeps the leadscrew turning without it. Don't be afraid to take things apart, you will gain understanding and could possibly solve problems that have frustrated you in the past.

Cheers,

John
 
That's odd. I don't have your machine, but I do have a Jet 1340 and the manual shows a pin, which is what I've always encountered on other lathes I've worked on. Your manual doesn't show what is used?
You said you can move the lead screw to line up the hole. Are you saying there's a hole in/through the lead screw?
The manual does not show a pin or set screw or anything. There is a collar or bushing on the lead screw and that turns inside the black piece. The
Black piece has a threaded hole and the bushing does not Maybe the lead screw is keyed to the bushing and a set screw goes into the bushing . I will have to clamp the black gear box output and then rotate the lead screw to see if there is a hole in it. Will check tomorrow. Still wonder why there is not a hole 180 to the existing hole that is there. If pin sheared how would you drive it out.
 
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