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Admiral Bosch posted:Alright, I finished my CNC machinist certification and I've been job hunting for about a month and a half now. Still nothing concrete, but it's become abundantly clear that my education was really lacking in the GD&T department. We studied it for all of one week in my quality control class instead of in the blueprint reading class for some loving reason. So, in order to better myself and not gently caress up on a potential job, I'm looking for a GD&T for dummies guide. I have my textbook, and I'm gonna go through that too, but if there are some online resources that aren't really dense that someone knows about, I'd appreciate it. And yes, I am googling as well. Just thought I'd ask here. For less than $10 you can get this on Amazon : https://www.amazon.com/Ultimate-GD-Pocket-Guide-Y14-5-2009/dp/092452023X/ I don't have that exact one, but an older one that CAT put out that's nearly the same. Where are you located at? What sort of shop are you looking to get into?
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Jun 25, 2016 01:12
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Admiral Bosch posted:I moved to the Boulder area and have interviewed at a few local machine shops and companies. Ideally I'd like to be in a small shop where I can get better at not only the trade, but see how a shop functions overall. Unfortunately I don't know any shops out that a ways. A lot of Rocky states shops, especially the smaller ones, have been hit hard by the low oil prices. That sweet sweet oil field work took a serious dump. I'd keep knocking on doors, and keep knocking, and if you find a good door just keep returning. We had a great hire who'd come in once a week, check in, not be a nuisance, then take off. Like a year later we hired him.
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Jun 25, 2016 13:24
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Admiral Bosch posted:Whee, got employed at a local machine shop today, they seem to do mostly aerospace, medical and other precision contracts. gently caress an oil contract. Now I just have to make it through the 2 week evaluation period and make them realize how great I am. Awesome dude. The one thing I really like in a new guy is cleanliness. If you keep your machine and work area just as clean as the cleanest dude in the shop you'll be well liked. Do this even when they move you onto a dirtball Morey from 1954 that no one has cleaned since then. Maintenance will like you. The engineers will like you. Management will like you. edit : Strive to get onto the most precision equipment they have too. Come layoff time you'll look more attractive if you're the only dude that can run the Jones and Shipman ID grinder.
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Jul 7, 2016 21:59
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Admiral Bosch posted:Was having a discussion with my boss the other day; we were playing around with one of the proven programs trying to get a countersinking op to stop building up chips on the tool. I suggested using a fluteless countersink, as I always had good results with that when I was in school, but he says the way they're designed, they essentially cut out a radius, instead of a flat angle countersink. But if that's the case, how do they market them as being 82 deg, 90 deg, etc? Like these: http://www.kaufmanco.com/itemdetail/WLD%20CS-8S We almost exclusively use the style you linked to. The multi-fluted cutters always seem to do a shittier job.
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Jul 15, 2016 16:06
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Cakefool posted:Suggestions? We maintain some ancient equipment and see variants of this often. What was proper at date of manufacture was revised at some point in history. Someone like Hardinge is pretty good about tracking those changes. Smaller manufacturers... not so much. When it comes to stuff like that we apply something like Torlon or Glacier DX to the worn out gib and scrape it in. A Biax scraper would be overkill for this, you'd be fine with a hand scraper.
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Jul 28, 2016 17:18
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Cakefool posted:Ran out of adjustment on the current ones (not enough meat left to drive further in and take up the slack) You could take heavier amounts, but we'd usually do that on the surface grinder first. For some of the bigger dovetails and such we've got special cutters and stones to get into the corners. Our equipment is almost entirely centerless and OD grinders, so they don't see anywhere near the wear a high use lathe would. That and they tended to protect the ways and design it to shed grit better.
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Jul 29, 2016 12:01
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Bring out the monster magnetic sine plate! You know, the one someone bought at an auction that was certain to get used once every 27 years. Is it a hardened gib? Do you have the fixturing to to do it on the mill?
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Jul 29, 2016 12:24
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Pagan posted:Can anyone talk about files, in detail? I'm talking about bastard files, mill files, hand files, etc. I know the basics of how they work, but where do I find good ones? How do I maintain them, aside from "don't drop them"? I purchase exclusively Nicholson files, usually in a 10 inch bastard mill. MSC carries them for like $13. Be sure to order a handle, they normally don't come with one. Don't be that guy with a wicked scar in the center of his palm that starts the story with, "So I was deburring a nasty casting on the lathe..." I have a pretty massive selection of files and rarely use any but the bastard. The precision swiss are neat, but if I need something that nice we just stick it on a surface grinder. It's too hard to remain parallel and flat with a file to any precision. Nicholson has a guide as well with a ton of info - http://www.nicholsontool.com/MagentoShare/media/documents/nicholson-guide-to-filing-2014.pdf
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Aug 19, 2016 18:48
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Slung Blade posted:Man they've come a long way with that tech in a year or so. This is the future. What are they going for now? If that thing can clean inconel... oh boy.
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Sep 5, 2016 01:31
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Get good with a quality micrometer and you'll feel dips and bulges on a shaft in the .00005 range. It'll be beyond what your mic can read, but you'll feel the tight spots-loose spots. Then to verify stick it into a laser mic, and whammo, there it is.
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Sep 28, 2016 15:37
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Gray Stormy posted:Im in the process of finishing my coal forge build and I realized that I still dont have an anvil. If you are where I think you are, head down to Coplans on Saturday morning and browse through the steel pile. You're likely to find a chunk of steel that meets your needs. You'll get it for scrap price which is some ridiculously low value right now. Just beware you might get an alloy of steel that you can't touch without carbide tooling. Barring all of that PM me and I'll try and track you down a cut off.
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Nov 7, 2016 01:04
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Gray Stormy posted:You seem to know EXACTLY where I'm at If you need a "nicer" barrel let me know. I just got a shipment in that are European sizing with locking lids. They're cool looking barrels, at least as far as barrels go. I lurk in TFR and saw you mention our area a few times before.
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Nov 7, 2016 14:36
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I've slid small machines (bridgeport, surface grinder, OD grinder) off of forklift forks and even that felt sketchy. I couldn't imagine doing anything of any size. We purchased a brand new grinder, had a massive forklift unload it, spent a week setting it up, leveling it, vibe damping all of the pads, basically making it a big beautiful cell. The sales rep, and the grinder rep both showed for the initial fire up. We hit the power. Boom. Blew the fuses on the rail. We put in new fuses. Boom blow those too. It was at that point we realized that the spindle was seized in the housing. It was the first of a very long string of terrible design discoveries. Had we been sharp we'd have had the forklift come back and load it onto another truck. After that I had to design and program a new CNC system, then the dressing system went to hell, then the angular slides seized up as there was no oiling, etc. etc. To top it all off the service and parts department is so terrible that I can't even get replacement parts for it. So now we machine them all ourselves, scrape them in, and hope the machine base doesn't crack. Long story, short, if a machine costs 50% less than the cheapest competitor, run. Fast.
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Nov 16, 2016 16:25
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shame on an IGA posted:Place I work rented a 70 ton Liebherr boom crane and operators for twelve hours just to unload a centerless grinder off the truck. Hello there fellow centerless grinder dude. What kind of machine did you buy? It's rare I run into someone who knows what they are, let alone buys one.
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Dec 1, 2016 00:35
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shame on an IGA posted:I'm an ex-lathe guy who somehow got turned into a controls electrician, they just put me on this to unwire the control cabinets on the two old rear end Cincinattis that had to move out of the way and osmose as much millwright knowledge as possible from the contractors. New baby is a Mikrosa M400, from what I've seen of the other one they already have it is a 95% uptime through-feeding 24/7 beast. That's one hell of a Swiss machine. The only one nicer would be a custom Junkers. We run a fleet of cinci's that do nothing but infeed. We've never even attempted through-feed. Have fun with it!
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Dec 1, 2016 01:37
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Brekelefuw posted:Cheapest set on ebay.ca is $1600.... McMaster Carr has them as well for $9. https://www.mcmaster.com/#chucks/=15ak5n2 No idea if Mcmaster ships to the US though.
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Dec 2, 2016 14:24
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Super Waffle posted:I thought they didn't ship outside the US Derp, I meant Canada.
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Dec 2, 2016 18:24
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biracial bear for uncut posted:How do you go about vetting that a particular lathe is any good if you find one locally, anyway? I'm not a fan of repainted / "reworked" ebay machines. We picked up a Bridgeport two years ago that was repainted and rescraped, though whoever did it had the talent of an orangutan. A few hours into running the machine and the quill feed broke then the power feed went. The table was out of square and had a funny sweep to it from where whoever flaked it didn't actually scrape it flat. I much prefer a well cared for, original machine. All the painting and scraping does is hide defects. I'd look at spindle runout, true flatness of the running surfaces, the crankcase oil condition, and peek into the nook and crannies. If I saw any evidence of a toolpost grinder being used I'd run. Beyond that look for a reputable brand and see what parts are available. I also check the electrical system too, a lot of machine tool coolant degrade the plastics. Nothing like a three phase contactor shattering apart.
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Dec 15, 2016 17:59
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I thought he was skiing, like a holiday themed dickbutt.
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Dec 22, 2016 14:25
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CrazyLittle posted:well, you can't break the dial on one... We still use vernier calipers and mics on ops where the parts are acidic. IP67 only lasts so long against corrosive liquids. The R&R's are surprisingly good with a skilled operator.
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Dec 22, 2016 20:52
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Rapulum_Dei posted:And then this morning I see this https://youtu.be/nNEcoBdIsnc I love poo poo like that. I gently caress around on my mill, some time in the backyard, and I have some cool looking gun sight or resin cast thingie. That dude makes a pot that totally enriches someones life in the most basic way. Now they can cook. Kinds of put things in perspective.
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Dec 28, 2016 13:28
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Ambrose Burnside posted:cleaning up in the garage and found lots of artifacts i forgot about making at some point, including this lovely h.r. giger-inspired foldformed cockring from a couple years back. iirc it was a "I like your work, surprise me with something for a dick" commission where payment never materialized. freakin, salud So, uh, how does one go about getting a Level 4 PPAP for a cock ring?
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Jan 10, 2017 02:27
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mekilljoydammit posted:Muhuhahahaha... I think I've secured permission to sell cast versions of that Fury Road skull shifter. I have no idea how to price something like this though, so... uh, thing like that TBA? Or should I kick that over to an SA-MART thread, I'm really a newb at selling poo poo on forums or otherwise. I'd get an interest check, figure out your order volumes, and give a price range. From there you could do a few ways. Cost method : ((materials $ + labor $ + IP $) * (1+Profit Margin % ))/finished parts Rules of Thirds : 1/3 for Labor, 1/3 for Materials, 1/3 for Profit Or just look at comparable items on Amazon/Etsy and fall in the middle. You could also just pull a number out of your rear end and run with it. You'd be surprised how many fairly large businesses go with that. Edit : Count me in for one too, as long as the price isn't ridiculous. Yooper fucked around with this message at 17:14 on Jan 11, 2017 |
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Jan 11, 2017 17:12
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Someone came into our shop today and sold us some sheet metal tools. Usually people bring in junk they find from when their grandpa was a tool and die maker. Old swaging blocks, a starret mic so old Jesus used it, or a box of "expensive" HSS lathe bits. Once we got a 12 foot long boring bar, another time a hand made dividing head that is a work of art. I noticed some stamping on the tools, and saw this...  All of the blocks and bits all were originally for doing sheet metal on B17 bombers. How loving cool is that? They look ground on and such now, but it's a pretty sweet little collection.
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Jan 14, 2017 01:50
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Lemme look into it. Our maintenance supervisor bought them, if he'll part with one I'll snag it. This was the best looking of the tools, all of the others we're cut or notched or beat up in some odd way.
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Jan 14, 2017 12:48
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Pagan posted:I have some quenching questions. I've been working pretty steady these past few weeks on knifemaking, and this weekend I had three knives all break during the quench process somehow. What looks easy from the outside suddenly has a million details when you're doing it in person. I've not done blades, but I've hardened dressing masters which are a bit thicker. Did you normalize it? Is it a spring steel that may have retained memory? Keep it in the quenchant until it's normalized temps with the quenchant. This is probably overkill but time was never an issue for me. When it warps, temper, rest, temper-soak, and try to straighten it while still hot. Found this on bladeforums : quote:Learning simple straightening practices will help you remove warp. Learning basic HT metallurgy will help you know when you can remove it. There are times when you can easily straighten warp, times when it will laugh at you for trying, and times when it will make you cry.
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Jan 16, 2017 13:29
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I use peanut oil myself for oil or water quench steels. We don't do much work of that sort so I've never bought any of the fancy tempering oils. Even the water hardening steels in oil gives us more consistent results than using water.
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Jan 16, 2017 18:44
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Some big ole diesel exhaust pipe with a cap welded on one end maybe? If all you need it a long vertical container I think it'd work OK.
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Jan 17, 2017 02:59
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BlankIsBeautiful posted:That.. is interesting. I figured the OA would be quicker since finish is not a final criteria. I'm just going to stick an outboard in it. If I was fabricating a smoker, I'd definitely do cleaner work. Regardless, I'll have a look a the drum, and see if that will do the job. Thanks! Definitely do the angle grinder with cutting disk. You'll be done much quicker, have a better result, and no worries about the volatiles boiling off in the oil and exploding.
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Jan 24, 2017 13:22
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Mudfly posted:How do you make a long surface (1-3m), such as the top of a bar or beam, or the bits a lathe moves across, really really flat? If it'll fit (our scrapings range from 30cm up to 2 meters) we start on a surface grinder or blanchard grinder. Then we break out the Biax scraper and finish with a Biax flaker. We have some 2m long whaleback straightedges along with a pretty massive granite plate. On our machines, grinders and such, the carriage assembly is typically long enough that it has an averaging effect so any dips or rises get cancelled out. How it's done on something like a massive gantry mill is beyond me, but when your machine bed is 20 feet long your thermal expansion is going to be larger than whatever your scraping tolerance is. I know what you're asking, say you had a fifty foot long iron beam, it'll be drat near flat using a six foot straight edge, but from one end to the next could vary in height significantly. I'd be very curious to know, especially in regards to a linear rail guide.
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Jan 26, 2017 04:33
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It's really cool to watch the leap frog of fabrication to materials to design. At first they couldn't make it, then when they could the materials couldn't handle it, and then when the materials could they could iterate on the design. Which brings you back to step 1 and needing tighter tolerances or novel manufacturing methods. In the 1830's Whitworth came up with the three point scraping method which really allowed machine tools to go from a one off artisan tool into something that could be mass produced and mass produce. Follow a generation later and you see HSS emerge as the dominant force and change everything once again. A generation after that was carbide, and shortly after indexable tooling, all following the same pattern of fabrication to materials to design.
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Jan 28, 2017 04:00
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Normally you use a mill or surface grinder to do the heavy work and finish it with scraping. You really don't want to scrape much as it's very time intensive and really a pain in the rear end.  The picture above is a Biax flaker, which makes those cool looking J patterns. That's done after you've scraped it with a very similar but altogether different Biax scraper. How accurate are you looking to make it? I've designed and built a few machine tools and can offer a bit of guidance. The latest one we're looking at will use a composite concrete base with Rexroth or SKF rails. The days of scraped ways and dovetails gibs are going the way of the dinosaur. The rigidity given by the crossed ball linear rollers is really amazing. Thermally things get interesting too, that's one reason a good machine tool is big and beefy. Your rail system can be really big and strong but if whatever its mounted to can flex than you'll get weird dips and rises on your parts. Definitely post some pics, I'd love to see how it progresses for you.
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Jan 28, 2017 14:55
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Pagan posted:Put that one right next to my imaginary copy of "The Knight and The Blast Furnace." quote:The three plates are marked 1, 2, 3, for tracking in the process and scraping operation commences. High spots are seen when bluing from one plate is transferred to the surface of the other plate. Six steps are involved in scraping these three plates. We use Biax scrapers and tubular hand scrapers. Camelback castings and straight edges are on eBay alot but be aware that most will come machined, and not scraped. If they are scraped consider them suspect until you've hit them with some bluing. We've had good luck buying from Suburban Tool, but again, you need to scrape them in yourself.
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Jan 28, 2017 20:18
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That Foundations of Mechanical Accuracy is pretty awesome. Moore Tool sells it for $150, but like the third Google result is some universities online version. Where I found this gem :  And this :  Oh dear.  Where have you been FOMA. This book is awesome. 
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Jan 29, 2017 00:51
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Brekelefuw posted:EDIT: Derp. just found this. Seems perfect. http://www.starrett.com/metrology/p...#Specifications Those work very well, you just need a very gentle touch when setting and measuring them. For the best accuracy don't use the clicker on the micrometer and calibrate the mic just prior to measuring.
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Jan 30, 2017 00:33
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Got a cool phone call yesterday in regards to machining some parts for a mega yacht. Not just any mega yacht, but a mega yacht built by Krupp in 1928. If it goes through I'll post some pics as this is a pretty cool looking project. About once a year we get a call like this. Last year it was for a 1904 French Firetruck. The year before that was parts for a P-51 Mustang. Usually it's some old guy looking for parts for his 1934 Ford Tractor.
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Feb 10, 2017 13:07
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A Proper Uppercut posted:'Sup fellow (what sounds like) machine shop employee guy. Hi Dude. Northern Michigan. We've got a fleet of centerless grinders, one CNC lathe, a pack of angry surface grinders, a handful of OD grinders, and a bunch of custom designed grinders. We pretty much do nothing but round parts, the surface grinders are just for us to rebuild our own equipment. There's also one lonely Bridgeport knock-off. We're probably the only machine shop around that spends less than a $100 on carbide per year.
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Feb 13, 2017 19:38
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Volkerball posted:I'm guessing you guys do pretty much nothing but grinding then? That's interesting. I didn't know there were shops that specialized in that. I run mills at a weapons manufacturer. We've got mostly mills and a few lathes, all Mazak. Then a handful of saws and manuals for various small applications. We probably spend $100 a day on carbide. Inserts add up quick. All our parts pretty much come in as forgings and we machine them into finished product from there. Grinding, and pretty much only one part in different sizes. We also have a hard chrome plating operation that is our niche. (No, we don't chrome bumpers, gun slides, ornamental poo poo, or dildos.) The big specialty for a centerless is roundness and tolerance on a small diameter part. Sure you can turn a 2 inch shaft to a few tenths tolerance, but try it on a 6 inch long shaft that's only 1/4" diameter. The centerless also removes out of round so you get really perfectly round shafts, compared to a lathe or OD grinder that makes lobed parts. We've managed to find a good niche, that's hard to replicate, become very good at it, and avoided the race to the bottom that have killed so many machine shops. I like Mazak stuff. We were going to buy one of those instead of a Haas but the Haas guys threw in a bar feeder. In hindsight I wish we'd have bought the Mazak. Weapons like handguns and AR's and such? That always looked like an interesting, but ultimately low profit, niche.
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Feb 14, 2017 13:44
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Volkerball posted:I started off on Mazak's so I've always been more comfortable with them. The programming is just so much more straightforward. Haas' aren't bad little machines but I've seen some pretty chintzy ones. We had a bunch of their mills and it always seemed like at least one of them was broken down at any given time. That your issue with yours? Our Haas gets about 10 hours of use a month for one particular part. It's still in immaculate shape. There's a shop down the road that has a ton of them, they never exceed 85% feed and have no issues. Like you said, can be chintzy, but as long as you don't push them like a machine that costs 5 times as much you'll be fine. I'm actually an EE but spend most of my time doing Manufacturing Engineering. It would behoove you to learn R, especially in relation to SPC. You'll blow people out of the water that are using just Excel. Minitab isn't bad, but if you've got your R groove on you'll do damned good work.
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Feb 14, 2017 16:25
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Volkerball posted:And thanks for the tip, I'd never heard of R before. I'll have to dig into that. If you're in any sort of modern shop you'll do a lot of data driven poo poo. Gone are the days of hunches and wild rear end guesses. Profits can be so slim and volumes so high that trending is critical. Being able to present your data visually goes very far to state your case. Excel really sucks too.
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Feb 15, 2017 20:48
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