I had to machine some 3/4 304 stainless round rod last week, and it performed a little oddly. I first noticed it on the band saw when I cut the slugs to machine. They would cut with a kind of eye shape on the end. Then when I cross drilled it I noticed I got beaughtiful continuous curls about a
1/4 of the way in, then through the middle it gave me kinda nasty looking munched up looking chips, and as it approached the other side nice pretty curled continuous chips would start coming out of the hole again. I drilled them on the KMB1, so feed was consistant.
It was like the surface 1/8-3/16 was what I was expecting, and then the middle was something totally different.
When I milled the hex half way through to engage the pins I didn't notice anything odd, but that was planned to be a pretty light fast cut.
I have no idea what it means. It was just seemed odd to observe. They are just cross handles for a core pull pin so the alloy is really not all that important. Just needed to be stainless.
'Don't know the answer to your dilemma, but a clue might be the fact that a cold-rolled stainless bar generally is harder on the outside than in the core. This is true of most steel grades, but moreso with stainless, and the effect is greater as the bar gets thicker.
I think you're right on the 'eye' thing, have seen that too, and sometimes on other materials.
I've spec'd a couple items I've sourced out here in 303 for easier machining. Nobody seems to know what it is in rural AU. Everyone out here uses 304 or 316 in the abattoir industry.
Interestingly I made the pins with 303. My plan was to just bend an L bend on them, but I decided I needed to make a bending jig to do that well, and it was faster to machine the ends and put cross handles on. My local metal yard (the one I like) only had 304 on hand.
I am aware of stainless work hardening, and took a fairly agressive feed I thought. I got beaughtiful continuous chips to start each cross drill. Maybe I should drill more agressively? Maybe even program stuff like that with a particular familiar stock with three drill operations?
What do you know about Inconel 600 for food, specifically for a thermocouple probe in simmering tomato sauce or acidic meat marinade? The applications tech at Omega knew even less about it than I do.
The probe I bought from them reads 212.1F in boiling water.
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"The main limitation with thermocouples is accuracy; system errors of
Yeah, anything in food production areas has to be food safe. And since nobody seems know even know what it is, certainly won't be an issue! People don't seem to get it when I sorta whinge about not being able to find things I want, tooling, hardware, etc. So have shown McMaster Carr's website to a few. Blew them away...
I've had fun collecting MSDS for everything we use in the plant, and sorting out what's food safe and what's not.
Regarding 303, my recollection is that there is no toxicity issue. It's the pitting that's a problem -- maybe from the sulfur content, but I don't remember the detail. Anything that pits or corrodes, whether the material itself is safe or not, is a harbor for bacteria.
Sometimes one doesn't appreciate what one has until one doesn't have it... Wish I could get MSC to open a branch here, but not sure there's enough manufacturing to support maintaining the inventory.
For the most part, available on the web here. Some items I've had to track down the mfg and request, and one outfit mailed them in. Even most Aussies admit the country is a decade or two behind the States in some respects.
Have had a lot to learn in this area. As if AU standards weren't enough, we're after export contracts in the States. Boy, has that raised the bar. It's not big issues, but a thousand tiny details that have to be attended to... The majority of work order requests I've processed lately relate to coming up to export standards.
The push for raising the bar has benefited me. Got another promotion, now maintenance planner. Being flown to Sydney Monday for 3 days training on MEX. I'm stoked. Place was mostly reactive when I hired in. Was my stated goal from the start to implement some sort of structure and system, even if only in the one area I was initially responsible for, rendering.
Now I'll be setting up PM schedules for entire plant. Stock yards, 2 slaughter floors, 4 boning rooms, 2 offal rooms, refrigeration plant, chillers and freezers, rendering, skins, bio remediation, waste water and irrigation as well as spares stores and inventory/requisition. As we have at least 18 months expansion to come, probably take 2 years to fully document all assets and set everything up.
Now that you've been there for a while, what do you think of the regulatory regime in the US versus Australia? I'm referring to such things as safety regulations at work and the food-safety issues you're dealing with.
Holy crap Ed, you almost gave me a heart attack! I wasn't paying close attention and I thought for a moment that you were replying to Jon Banquer. If Banquer had a job then what next? Flying pigs crapping all over my yard? Some poor employer being slowly driven insane? Fortunately reality returned quickly and I realized that Banquer was still safely hunched over his keyboard trying to influence the election the same way Wieber pretends he's a taxpayer. Whew!
Ha! No, Australia is no longer a penal colony. They closed Cockatoo Island a long time ago. Banquer is not likely to be shipped there when they finally catch him.
Hey, BTW, if you don't watch Bill Maher's show, "Real Time," try to catch tonight's show on HBO's later cable feeds or whatever. (It's being re-run as I speak.) He ran the funniest "commercial" I've seen in a long time -- a mock Bernie Sanders political commercial.
Well, worked 3 years at NASA Ames, high school and college work exp, almost 2 years at Spectra Physics, and almost 2 years at Varian. All the rest of my work was for small shops where safety was, shall we say, up to us, and insisting on it could cost one promotions, if not one's job (under some other pretext). Yeah, a few shit job shops.
Obviously, the three mentioned above had well established safety programs, and that was about the extent of my exposure to regulations. Then there was 20 years working out of my garage. I did more than a few things I would never have let an employee do. Paperwork was held to the absolute minimum.
So, I hired in the same week the sale to our corporate owners was finalized. Outgoing fitter, in one of the few bits of serious advice I got from him, told me to "watch my back because nobody else will, and there are things here that'll kill ya quick".
That had a lot to do with my joining the safety committee, were I got a
2 day class in WHS. And that really didn't come near fully touching all the regulations. We're implementing programs and controls fast as we can, but still have a ways to go. Some of it I think is over the top nanny statism. But it's all geared to keeping us safe. Because getting hurt costs the corporation money, and lost productivity. Hey, might as well be up front about it. They do care about us, but the class weighed in heavily on the long term costs to the company for injuries. And they are substantial! We're still working on issues of small town people that have never been expose to anything like the corporate world, and seem more concerned about getting pissed on the weekend (drunk) than worrying about things like safety. But making progress, finally went a month with no lost time injuries, something not seen in a long long time.
I've heard tales of companies with controls so strict, one had to fill out paperwork to change a friggin light bulb. Heaven help you if you gotta go weld on something. And an accident on the railroad apparently earns one a day or two of paperwork.
Since my exposure to regulations in the States is decades old, hard to compare. Things are different now I'm sure. But I'd say while AU is something of a nanny state, a lot of things Americans take as normal, are less common here.
On food safety, well, no training in that, and not needed for my work. I do see the issues QA raises, some of them seem annoyingly minor. But, when Safeway comes through to inspect, if things aren't up to their standards, you don't get the contract. So we're having to come up to US standards in that area. Seems to be less issues with food safety in terms of contamination, etc here compared to the states, so that seems a bit odd. but then, the whole dang country has a smaller population than California, so I'd expect less total incidents.
My attitude is, I'm getting paid by the hour, and paid well. They want me to fill out paperwork, I'll fill out paperwork!
As for the promotion, I'm 59 in a few months. Spent today replacing wear plates, screen and hammers in a hammer mill. Big heavy stuff. A desk job in a heated/cooled office is looking real good these days!
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