Broke my lathe PM1127

Pcmaker

Pcmaker

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I was swapping out gears to do some metric threading, did the usual insert paper in between gears before tightening everything. Turned the chuck by hand before turning it on to make sure everything's moving right

Turned on the lathe, it made some noise and before I could hit the stop button, I heard something fall apart. The gears fell off, thankfully not damaged, but found this part. It's the bolt that secures the change gears in place. It has a square head, with a button oiler on top. Snapped right off.

I emailed PM and hopefully I can get the part soon. I have a 1 week vacation coming up and I had plans that involved my lathe. If my lathe was working, I could just make one up that would work, but I can't. One of these broken means no lathe work. Period.

Does anyone know if these are common items I can order online for cheap? What are these even called. I've been having a hard time finding it on the diagram. I don't know how long for Precision Matthews to send me one and I'd rather buy a pack of these and have it arrive in time before my vacation.

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Pcmaker said:
If my lathe was working, I could just make one up that would work, but I can't. One of these broken means no lathe work. Period.
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Lathe will still work to make one without change gears. Just means that you'll have no power feed.
 
Alternatively you can cut the rest of the broken threads off. Drill & tap it & stick a threaded rod in it. Could probably even get away with just a press fit & Loctite. Can just use a bolt with the head cut off for the threaded rod. May loose the oiler function but you could add that too if you wanted. At least that will get you back up & running if Matt doesn't have the part in stock.
 
Have you done an analysis of why it broke? Your description indicates you set it up correctly, but do we think is was just old age did it in?

jack vines
 
I'm not exactly sure what I did, but I think I didn't tighten it enough and the gears moved while the lathe was turning.

As suggested, I drill and tap the broken piece with an m6x1.0 threaded rod from Amazon. My die can't start cutting into a 5.8mm rod for some reason. Probably all dulled out.

I hope I will be able to somehow get it in the lathe chuck to center drill and tap
 
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I faced the part, then center drilled

I'm using a 4 jaw independent chuck, I"m gripping it by the square head.

I'm having trouble with concentricity. I used an indicator on the end and got to .001, but the left side is off by .005. Not sure what to do to get it concentric

I need to get both sides close, I might have some issues when I start to drill and tap into it.
 
It doesn't turn in use so concentricity is not needed.

I see, you're concerned that if it isn't concentric it won't also be straight. Yeah, holding by the square you run that chance. Hold it by the shaft if you can.
 
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I'm afraid that while it's stationary, if it's not concentric, the gear won't be square to the banjo and will wobble slightly while turning
 
Pcmaker said:
I'm having trouble with concentricity. I used an indicator on the end and got to .001, but the left side is off by .005. Not sure what to do to get it concentric

I need to get both sides close, I might have some issues when I start to drill and tap into it.
Click to expand...

Instead of holding it by the square head, seat it deep enough in your chuck so the threaded section is in past the bottom edge of your chuck jaws and hold it by the round shaft. After you drill and tap it be sure and not seat your stud too deep so you don't block the oil passage.
 
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