# Things I Make And Cut On At Work



## Wreck™Wreck (Nov 25, 2016)

Nasty turning job on Wed., 10 1/2" Dia. plastic bead impeller for a large scale injection molder, 304 stainless weldment.

Turning the bearing journals at 350 rpm's turned it into an excellent fan, facing the vane ends was a testament to the Sandvik SS interrupted cut inserts which worked flawlessly considering the conditions, I faced it at 90 Rpm's and it still sounded like a train wreck.

Safety First, I stood 5 feet away when it was running.




Some .001" shim material was required in the center to reduce the run out, this can be a maddening process at best.


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## Tony Wells (Nov 25, 2016)

I would have recut that center. Obviously the shaft is bent or distorted from the welding. Next guy would thank you.


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## Ulma Doctor (Nov 25, 2016)

Wreck™Wreck said:


> Nasty turning job on Wed., 10 1/2" Dia. plastic bead impeller for a large scale injection molder, 304 stainless weldment.
> Turning the bearing journals at 350 rpm's turned it into an excellent fan, facing the vane ends was a testament to the Sandvik SS interrupted cut inserts which worked flawlessly considering the conditions, I faced it at 90 Rpm's and it still sounded like a train wreck.
> Safety First, I stood 5 feet away when it was running.
> Some .001" shim material was required in the center to reduce the run out, this can be a maddening process at best.



Hi Wreck!
i don't envy your task above!
everytime i gotta work 304, i say the old mantra- 304 is a ....(explative)

i'm curious how you came up with the shim placement and thickness?
at the risk of sounding dense, i think i am i overthinking this,
was it just indicateing poorly and you found the low?
or what it the PITA i thought it may be?
i have not had the pleasure to try, or had the real need, to work from a poor center like that.
it is nice to know that out of the box doing, accomplishes things that thinking , never will
nice job, good save Wreck!


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## Wreck™Wreck (Nov 25, 2016)

Tony Wells said:


> I would have recut that center. Obviously the shaft is bent or distorted from the welding. Next guy would thank you.


Not bent nor distorted (machine after welding) simply the normal difference between machines, it had a TIR of .003" as is, which I find excellent on a used part 20" long, I do not pursue the .0001 hobbyist penchant for accuracy only what is required for the job at hand. 

As far a drilling a new center this would require setting up a steady rest to do so, also the next person will put this part in a different machine. For all I know the .003" was in the live center  that I used.


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## Tony Wells (Nov 25, 2016)

I know what it would have required, Wreck. And re-drilling is not it. Yes it would require a steady rest, but that's no biggie. I never suggested that a tenth runout would be needed. Remember, I'm not a hobbyist. But obviously you thought the 0.003 was unacceptable. It would have taken about 2 minutes to check the center. Was runout spec'd on the print? Are you going to discard that center if it proves to consistently run 0.003 out? It seems either that center or the one previously used to turn the part, at least where you were indicating, is at fault.

Just curious.


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## Wreck™Wreck (Nov 25, 2016)

Ulma Doctor said:


> Hi Wreck!
> i don't envy your task above!
> everytime i gotta work 304, i say the old mantra- 304 is a ....(explative)
> 
> ...


Common practice in a job shop, put the shim on the high spot, common paper works well for small parts, this may take considerable time to get right however. This part only ran out .003" total which would be more then adequate for what it does, I tucked a piece of .001 steel shim into the center and it then ran out .001 the first time, pure luck, if it had not corrected after the first try I would have just turned the part anyway.


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## Wreck™Wreck (Nov 25, 2016)

Tony Wells said:


> I know what it would have required, Wreck. And re-drilling is not it. Yes it would require a steady rest, but that's no biggie. I never suggested that a tenth runout would be needed. Remember, I'm not a hobbyist. But obviously you thought the 0.003 was unacceptable. It would have taken about 2 minutes to check the center. Was runout spec'd on the print? Are you going to discard that center if it proves to consistently run 0.003 out? It seems either that center or the one previously used to turn the part, at least where you were indicating, is at fault.
> 
> Just curious.


You do not often use a 500 LB steady do you? I also know how to indicate a live center however buying a new 7MT live center is not something that makes my employer smile.


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## Tony Wells (Nov 25, 2016)

Not in my shop, but I have more times than I can count, and larger ones as well. If your shop is properly tooled up for that kind of work, there's nothing to it.
I have yet to meet a business owner who smiles at the thought of spending money, but I have seen one literally bounce a handful of mics out the door because they needed to be replaced and no one said anything. He wasn't smiling then either. Spending money when it keeps from making scrap is an accepted business practice, smile or not. That smile is immaterial.


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## Wreck™Wreck (Nov 25, 2016)

Ulma Doctor said:


> Hi Wreck!
> i don't envy your task above!
> everytime i gotta work 304, i say the old mantra- 304 is a ....(explative)
> 
> ...


303 and 304 are excellent materials for turning, I have never had a poor finish in 304 until the tool fails, this might be after hundreds of parts, 17-4 is a bit harder on tooling,


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## Wreck™Wreck (Nov 25, 2016)

Tony Wells said:


> Not in my shop, but I have more times than I can count, and larger ones as well. If your shop is properly tooled up for that kind of work, there's nothing to it.
> I have yet to meet a business owner who smiles at the thought of spending money, but I have seen one literally bounce a handful of mics out the door because they needed to be replaced and no one said anything. He wasn't smiling then either. Spending money when it keeps from making scrap is an accepted business practice, smile or not. That smile is immaterial.


We are on the same page here, try and give a bit of guidance to people that request it, that is one of the reasons that I like this forum, I work in a shop with 7 other old guy machinists, all of which  know everything.


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## Tony Wells (Nov 25, 2016)

I found that when I was 15 and started working in a shop, everyone was idiots.....except me. Then after a few years they all got pretty smart. 

And you're right. Our job here as experienced hands is to give back what we were given (except all the hard times). There's not enough of us left, IMO, so let's make the best of this place. It seems to be working pretty good, judging from some of the projects we are seeing, and realizing that these are people who haven't had the opportunity to work side by side 8-10-12 hours a day with old wise guys.  They just have the desire and time to dedicate to learning. And the smarts to ask when they don't know something. I think it's great, myself.

And someday, Wreck....you're going to be one of the "7 other old guy machinists, all of which know everything". lol So hang in there. Everything I hear for our area leads me to believe we are picking back up and there will be a shortage of machinists. Hope that's true for your area too. I've already been offered another managerial position (50 man shop), but it's in Singapore. Pass. And several have called locally wanting me. Pass again. I have what I want in my own shop, just as soon as this broken leg heals enough to let me get back to a regular work schedule. This "taking it easy" is getting pretty old. I've re-written my QA manual, drafted all my hand sketches for my prototypes I am developing.....getting tired of sitting around.

Sorry for going OT


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## Tony Wells (Nov 25, 2016)

17-4 PH (AISI 630) is just about my all around favorite material, as stainless goes. I don't care so much for tapping tiny holes in it when it's already aged to H-900, but at H-1025 (most common in downhole tools) or H-1100, it's great stuff. And very strong. Doesn't cut quite as easy as 303, but infinitely better than 316 or 316L. Never cared for 304 all that much either. There are better materials for mechanical components. It's great for fabrication and ornamental work though. Those (304, 316, 316L) I can live without, even though there are much worse "stainless" materials out there.


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## 09kevin (Nov 26, 2016)

Tony,
If I or anyone else I work with intentionally tried to hide defective parts we would be fired.

Kevin


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## dulltool17 (Nov 26, 2016)

09kevin said:


> Tony,
> If I or anyone else I work with intentionally tried to hide defective parts we would be fired.
> 
> Kevin



As it should be!


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## Tony Wells (Nov 26, 2016)

Agreed, but it does happen. And unfortunately it doesn't all get caught. And I have terminated people for it more than once. Never the same people twice though. Those don't get rehired.


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