New To Me, Jet 1336pbd - With Some "issues"

Okay, Pierre, after holding it against the seal I have to agree, but I suspect it went too far past the edge. The spacer has one edge that has a larger chamfer. Should that edge be on the seal side or against the gear?


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I had the spindle out on the Jet lathe, at work, a few years ago to replace the seals and check the bearings, so this is just by memory and may not be 100% correct.

In looking at my assembly page in the printed parts manual, to refresh my memory, that came with the lathe, #35 is the spacer you have posted the photo of. The chamfer is the side that enters the seal. It is also the side the o-ring #37 will seat against. It is to stop that pesky leak! The oil seal is 70mm ID to fit the OD of the spacer while the o-ring is 60mm to fit the shaft that the spacer rides on.

As for that HUGE amount of play that you have, #43 locking nuts push against the following items in order - #42 50T gear, #38 spacer, #6 outer bearing. The next 2 parts #37 o-ring and #35 spacer are held in place via that set screw to the spindle. They are not involved in the bearing preload that is next. The spacer #35 is actually there to fix the location of the #34 44T gear and the 3 groove pulley #30. They just sit on the spindle and run on the bearing #32. So that spacer sets their furthest left they are allowed to move and the #29 74T bull gear sets the right side. There is a shoulder that the bearing #6 is seated against on the inside of the casting so that it can not go in any further and by adjusting the #43 locking nuts you tighten them to reduce the play and set the bearing preload of the spindle itself.

I think that the above is correct but this was I believe atleast 5 years ago or more.

Pierre
 
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That's exactly what I hoped. So whoever took the spindle out and replaced the belt before me did not put that spacer up against gear #34. That's also why the spacer was so far under the seal. Also, there was no O-ring on my spindle.
Thank you!

I've got a question about removing the cones for the bearings also. Both are seated tightly in the headstock still. The bearings look like they're in great shape; no scuffing, scoring, or spalling that I can see. Do I leave then be and just clean the bearings and reassemble them, or remove the cones from the headstock first. My original thought was that since I've done this much I should put in new bearings, but I'm unsure that I can get the cones out of their seats.


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For our proposes I would leave them in and just do a clean and reassemble.

To remove the outer cones, 2 ways. Hammer and brass drift with lots of tap tap tap all around to slowly work them out and install new ones in. The second way is to make a cup or plate to be able to use a gear puller. Hammer and drift is the preferred way by most people. Obviously a good flush of the old lube to remove any debris in the casting is of benefit to the life of the bearings. I remember when we got the Jet new, I flushed out the lube first before even spinning it up and then did it another 3 times to get clean. There were still some marks on the races when I opened it up but not enough to replace at the time. The lathe is now 15 years old and still running on the original bearings. I change the oil from time to time. It only runs a few hundred hours a year as most work is done on CNC and Wire EDM in our shop. I have not opened up my clone at home as of yet, and it is much older than the Jet.
Pierre
 
Thank you again for your help. I described it wrong. The cone for the inboard end of the spindle stayed on the spindle. The cup for the outboard end stayed in the headstock. I think I will do as you say, just reassemble with a new bullgear and belt. If I discover later the need to replace the bearings I know how.


Steve Shannon, P.E.
 
How do those of you who repaint your machines remove the drive pins without marring the metal plates they hold?


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I might be stupid or I might be hard headed; I guess we'll all know soon! I'm convinced that the headstock gears and pulleys in the Taiwan built Jet 1336 PBD that I have are so nearly close enough to the mainland China built BDB-1340 that I can use the BDB parts to replace the broken bull gear and backgear in my PBD. PDentrum was kind enough to measure his backgear (as well as possible without taking his work lathe apart) and found it to be very close. I was hoping that the Jet parts store would let me return them if I'm wrong. Turns out they won't and they told my local Jet Service Center that the parts won't work. I ordered them anyway. I think I can make them work.
Wish me luck!


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Thanks for all your help and encouragement, Pierre!


Steve Shannon, P.E.
 
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