Logan lathe - reverse feed lever broke

Hey all,

Just fyi, today I was using the Logan lathe, and trying to change gear with the reverse feed lever, the lever snapped off. The lever looks like it had fractured here previously, and had been welded. I am not sure the next course of action to take. Unfortunately, I am not skilled in welding.

@rustin.atkeisson

Pictures or it didn’t happen

It did! I forgot to take pics I swear lol

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The lever itself is ok but the release lever is broken at the spring. This was a poor design imo, as it weakens the casting right where the spring pressure is applied. It has been welded before. That is probably a good enough reason as any for it to fail again. Cast iron does not weld very well without a lot of care and I would guess this was just mig welded.

It is quite a task to remove the reverse tumbler, not something I want to do in the wee hours of the morning, so it’s left operational. There is a set of vise grips on the machine in case somebody needs to switch directions before we can fix it. I don’t know how available this part is, but I would guess it’s probably broken on a lot of machines, so the are probably not a ton of them floating around. I would suggest that the tumbler be removed so we can make a new release lever from steel, maybe even beefed up in the weak area.

You might also notice if you look closely at the weld area, there is porosity in the weld. That is a result of the machine having lots of oil on it and cast materials soaking up that oil because of their porous nature. This likely would have been better solved by brazing the part rather than attempting to weld it with improper procedures.

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For anybody looking to buy some parts, here is the reverse lever assembly (I think this is the right one) on ebay for $150. Actually I don’t think it’s right, but you can see these parts aren’t cheap.

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I finally looked at it first hand today.

Since it’s a portion of the mechanism, I’m tempted to try machining it from steel bar stock… Problem is it might be a week before I can get to it, if I’m lucky. Sorry guys.

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Something even I’m guilty of… we all need to remember.

WE ARE ALL VOLUNTEERS

It takes time to get to things, a week is pretty fast. No need to apologize.

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Is there anytime we can come in and work on it together? I would attempt to start trying to fix it, but I’m very limited on lathe knowledge. I could probably disassemble it and reassemble, but I may run into some problems. I could get a piece of steel round stock and try to machine that. I would need to disassemble the lever to get some measurements though. I also have little experience machining steel, and I know it’s much harder to cut than Aluminum.

I was going to make it a weldment. The working end looks to be near 0.250" thick, so that could be machined as one piece then the fat end could be welded on and shaped with a grinder. That makes work holding easier for the holes that need to be drilled and such.

If you want to make it, go for it. If using hss tools, limit your spindle speed, use some sort of coolant if you can even if it’s just squirting it with some WD-40, and feed fast enough to make a chip and not rub. If you can use carbide, it will be much less stressful but I know the tooling is limited at the space.

I wanted to take the machine apart so I could model the handle but was afraid it would be down for a couple days if I do so. I sure wish we had another so it would just be a r&r operation. If possible, I would still like to model the old part before it’s discarded, even if somebody else makes the replacement part. I have to go to KC today but was kind of hoping I could work on it this evening. I don’t know what Rustin’s thoughts are on it being down for a couple days though.

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Does the entire tumbler/mechanism need to be removed? Or could we just tap out the pin holding the reversing lever in place, and replace it that way?

Looked to me like there wasn’t a lot of room to get in there with a pin punch but maybe with some creativity…

I also do not know how the lever engages the locking pin for the tumbler.

I believe we removed the pin last time. Here’s the related thread for reference: Lathe Repairs Needed

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Thanks for that link. Looks like I was incorrect about how it was repaired last time.

I am still in favor of making a new level from steel. That doesn’t mean it won’t stop break, and it will likely wear faster as cast iron Isa great bearing surface, but I think it would be better in the long run for a machine used in this environment.

Fyi… David beat me to it.

He is going to try machining a new one that has a bit more meat around the failure point. I hope he’s going the KC Strip route.

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I don’t like strip steaks. Filet or ribeye for me

Lathe is back to operating correctly. The lever in place now is temporary. I wanted to make sure the dimensions I got were correct before making a nice one.

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Nice job, looks like it will work well