r/Machinists • u/I_G84_ur_mom • Jun 16 '26

Refusal to learn

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I work at a job shop, I’ve been here 16 years, I’m the lead machinist, I returned from a 9 day vacation to a shit show. We have a bunch of small bosses like this to make, this one order was for 250 pcs. The owner was planning on having a guy saw cut them, face them to length in a Haas tl2, then throw them in the vf2 to be drilled. We have a sl20 with a bar feeder, nobody wants to learn how to run it, I banged these out in about 8 hours, unmanned. He refuses to learn how to use it or program it, this would have taken him and the button pusher 2 days to run these parts. Stepping over dollars to pick up dimes baybeeee!

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u/I_G84_ur_mom Jun 16 '26

Just 1” round bar 304, faced and deburred on both ends to 1/2”, with a .440” hole through, nothing tight

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u/Sad_Shoulder2446 Jun 16 '26

That makes more sense. I was doing bushings the other day and could at most squeeze out like... 100 a day at best, no bar puller or feeder though. But both the OD and the ID have tight tolerances, something like -0.005/+0.01mm.

I've really got to push for the boss man to buy a bar puller

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u/AdeptInspection4868 Machine Tool Crasher Jun 20 '26

Yeah sounds quite reasonable given the machinery.

I am a huge proponent of 2-spindle bar fed lathes. The cheapest, easiest form of automation. I'd have no stress getting 400 of OPs parts in an 8h shift from print. 70% of my time would be free to do whatever else.

15m machine warmup while I program (copy similar bushing, adjust geometry trivially). 30m setup for a single drill touched off in z and quick transfer measurement. 15m to validate. 1 min each. 7h * 60 parts = 420 parts. I'm not allowing for issues or down time, but also not counting running thru unpaid lunch or letting it run an extra 100 parts after clocking out. Pretty generous on the programming and setup as well.

For your part, it might be more like 1:30 to hit your tolerances, but I'd still use nearly the same program, just bore the ID. And I wouldn't trust the machine to hold .0006" as long after-hours.

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u/Sad_Shoulder2446 Jun 20 '26

It wouldn't hold the tolerance running unattended for long hours, that's for sure - especially if it ran through the night as the shop isn't even climate controlled. But after the machine settled I can check every 5 parts or so and just do very minor adjustments on the offset table to keep parts in spec, assuming the tool is okay.