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Kind of surprised how easy it is to keep a hole within a .0002" window with a honer. Those things are cool.
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Sep 28, 2016 13:50
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Pagan posted:What's the best eye protection for those who need glasses? I'm willing to spend decent money to keep my eyes safe, but so far I've been disappointed. First I tried these Side shields are fine for most applications.
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Oct 6, 2016 23:34
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Pop-o-Matic Trouble posted:I cant speak for blacksmithing, but at work they have palm coated gloves, and they're great. They're thick enough for tacking, torch cutting or light welding, and protect you from burrs and sharp edges, but also thin enough that you can use a soapstone or handle small screws. I put them on at the start of shift and dont take them off until break. You're not around any spinning machine tools like a drill press are you? It's pretty loving cool when someone gets some fingers ripped off by one because it zips the tendon out with the fingers like a piece of spaghetti, but it's probably not the funnest experience.
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Oct 18, 2016 13:27
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armorer posted:Thanks for that, but I really need this thing to be black. I might end up having to go with a baked on enamel finish or cerakote or something like that I guess. I work at a weapons manufacturer and I asked some guys in assembly about it. They recommended a cheap air brush, with two coats of cerakote. Then one coat of clear coat if you want it. Sounded like it's kind of hard to gently caress up.
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Oct 22, 2016 08:15
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Rotten Cookies posted:I love hearing about someone else's monumental fuckups. Two retired machinists came in today to set up our new (to us) shear and giant bandsaw. Someone tried unloading a big ol' CNC laser cutter by sliding it down a ramp into position. It tumbled. Then they tried flipping it over with a couple forklifts. It was apparently, uh.... unusuable. Lol. Did it break the floor?
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Nov 16, 2016 16:32
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walking through the parking lot to start my shift and i realize i'm standing in a fuckton of coolant. interesting.
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Dec 1, 2016 01:19
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i'm the guy at 17:01 using vernier calipers in 2016.
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Dec 22, 2016 17:22
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Ambrose Burnside posted:Verniers are "fine" and will be more precise + more durable than anything near their price range, so if it's fine for the tolerances you're working with, why not? TBH most of the pushback against Vernier-scale stuff I've heard comes down to "it's hard to read", which is a fair criticism but one that kind of goes away if you don't have crazy employee turnover and actually have to use the thing with any regularity. It's a bit like saying engine lathes are fine. Like yeah, they'll get the job done, but they're a bit dated is all. Feels like you're measuring parts with an antique. The vernier mics are still everywhere though.
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Dec 23, 2016 05:31
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Ambrose Burnside posted:I can't tell why they THREAD THE BONE in two steps. The first tap has a smooth section, maybe it guarantees the thread starts straight and even for the second tap to finish? Certain types of threads, like ACME, need a rougher tap to go through first. But roughers look nothing like that tool they use in the gif. They are chamfered at the end, and the threads gradually become more prominent down the length of the flute.  So either they're only making a general approximation of what the actual tools look like, or that rougher is something they engineered specifically for that application. I've never seen anything like it, and it looks like it's not something anyone would use for anything, so my vote is for the former.
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Jan 6, 2017 00:33
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Slung Blade posted:Anyone have a feed rate chart for bone tissue? evidently you need coolant. 
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Jan 6, 2017 01:17
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Magres posted:As best I can tell, you need coolant because the material you're drilling into (ie living tissue) is super, super sensitive to heat. You don't want to cook the person's bones as you're drilling. Why not? It should heat treat them and make them stronger. You could have a bionic mouth.
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Jan 7, 2017 00:41
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BlankIsBeautiful posted:Long time reader, rare poster here with a quick question. I'm building an outboard motor (9.9 hp) "test tank" from a 55 gallon lubricating oil drum, and various and sundry scrap that I have handy. I need to cut the top off the drum, and not having any access to a de-heading tool, plan to use the my OA torch to do the job. The question I have is, since it originally contained lubricating oil (which isn't particularly volatile), can I just fill it half full with water, and then proceed with the cutting? Or, should I try somehow to get the last remaining quart of oil out of the bottom, and clean it out? Signed: trying not to kill myself. Clean it and vent it. Even if that particular lubricant isn't volatile, the fumes from it could be when exposed to the heat. And even if they aren't explosive, they could be noxious. Volkerball fucked around with this message at 00:02 on Jan 24, 2017 |
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Jan 24, 2017 00:00
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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? With a big rear end press and a dial indicator. I never ran one, but at my last shop we ran a lot of big bars for combines and other large equipment. We had quite a bit of leeway with straightness, but we had an in house heat treat department, and that op would warp the parts pretty bad. So they would set up the press for the width of the part, and have a dial indicator checking the straightness as it came out. Then you just slide the part through and make sure it's coming out at 0 for the whole length. They'd do that right after they pulled the parts out of the oven. Generally we'd save heat treat for last that way the parts would go out the door as straight as possible. There were also some lathe parts we ran that would do it for you. Like if you have a 2" diameter shaft and you're turning it down to 1.969, it doesn't matter if the 2" shaft is a little bent. It's going to cut a perfectly straight 1.969 shaft out of it. Then it's just a matter of not bending it.
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Jan 26, 2017 09:03
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Yooper posted: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. 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.
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Feb 14, 2017 09:59
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Yooper posted: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.) We had some centerless grinds at my first job, but I never even went in that department. That was all outsourced parts from John Deere and Caterpillar, so they had a ton of different shafts. Deere hit a rough patch though, and now that shop is about on its last legs. It's too bad. That place has a couple hundred employees in my hometown of 3,000 people, so if they go under the city is pretty much screwed. Good to hear you guys have work. 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? And yeah, specifically AR's. This company started off as a boutique selling weapons in the $3,000+ range to rich enthusiasts, but within the last year they got a contract with New Zealand to replace their army's service rifle. So they've expanded a bunch since then to try and fulfill our contract, which is over 10,000 rifles. It's interesting work. We get all kinds of cool grenade launchers and machine guns through here from contracts with different militaries around the world. But the pay isn't top of the industry for sure. I'm going to school for manufacturing engineering right now, and once I've finished that up, I don't intend on sticking around for long.
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Feb 14, 2017 15:02
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Yooper posted: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. We used a lot of 2 and 3 inch insert mills that would hog through parts, so those machines were definitely dealing with a lot of tool pressure. It would feel like it was vibrating apart lol. The big Mazaks definitely could handle it better. And thanks for the tip, I'd never heard of R before. I'll have to dig into that.
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Feb 15, 2017 04:48
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Yooper posted:Leaving the chuck key in and starting the lathe.  My worst is probably the time I fed a 3" disk mill cutter into a 60" by 2" shaft without so much as a clamp in place because I got distracted during a set up. That's a big piece of steel to be bouncing around like a dropped pencil.  But my favorite story is the time I crashed a machine because I forgot a period. My Z wasn't high enough to clear the fixture when it returned to home, so I changed it from Z4. to "Z6". Since there was no period, it didn't read the 6, and it defaulted to Z0. So the cutter pulled up to the top of the part, and broke the bottom row of inserts on it as it went 100% rapid into the clamp.
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Feb 19, 2017 20:48
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Pagan posted:I now have access to a proper mill. Any good links or tips on beginner machining projects? Have you ever used one before? Is it a Bridgeport? What kinds of tools and material do you have available? If you just want to play around on the cheap, and you have a saw, I'd get a little bar of aluminum rectangle stock to practice milling parts square, and touching off x and y so that you can locate holes properly.
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Feb 26, 2017 15:45
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Wandering Orange posted:rotor's CNC thread What's this? Like a general CNC thread?
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Mar 8, 2017 12:39
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80k rpm? Jesus Christ. I don't think I've run anything above 15-20 Edit: Doing the math a .010 end mill going through steel would ideally have a spindle speed of 120k lol.
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Mar 10, 2017 08:12
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Mudfly posted:Thanks, looks like I need a dial indicator as priority no. 1 then? I am looking at buying a fairly cheap model (internet says not a big difference), and taking it to the shop tomorrow just to measure the difference from end to end on the x and y axis. Nah, you don't need to get too fancy with it unless you're going to be dealing with extremely tight tolerances and the table has to be absolutely perfect. The one indicator should be good, but you'll need either an edgefinder or a wobbler as well. Anyways, something cool happened at work tonight.  RIP tool pocket #17. Cheap machines always find the funnest way to break.
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Mar 10, 2017 15:36
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One thing with drilling is that if you're going through thin material, there's not a lot of room for variance in the table to affect the work piece. Like if you drill through a quarter inch piece of stock, and it's slightly raised on one end, the hole is still going to measure pretty center on the top and the bottom, as well as side to side. If you measure the top of the part to the diameter of the hole, and flip it over and measure it the exact same way, .005 is a massive amount of variance. That is a hosed up table/fixture. But if you're talking about a hole location that is +/- .020 with an allowable .015 centerline, who gives a poo poo? It's going to measure in tolerance everywhere, and be fairly straight. It just depends on your application. If all you are doing is punching holes through soft material and they aren't critical, you might be able to cut costs there. The spindle needs to be stable as hell regardless though.
Volkerball fucked around with this message at 20:01 on Mar 21, 2017 |
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Mar 21, 2017 17:23
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Leperflesh posted:The most important thing when moving extremely heavy things is fully internalizing that no matter how much money you spent on it, if it starts to go, you just loving let it go, you do not try to catch it. 100% this. When the point of no return has hit, get the gently caress away.
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Apr 5, 2017 22:46
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Try going a little deeper and a little faster feed. Aluminum finishes usually leave that chippy finish if you aren't engaging enough of the tool. That's why you'll get a pretty finish when you do a slot or drill a hole where the tool is completely engaged, but not when you just mill a bit off the side. You're also supposed to have the tool pressure going against the hard jaw but I don't know all the maths for that, so I'll just say you can also try feeding the opposite direction to see how that affects your finish. And if all else fails, there's always files for that sort of thing. Aluminum can be kind of goofy sometimes because it's so soft.
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Apr 9, 2017 21:25
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Mudfly posted:That's pretty cool, since there's no way I know of to add cast iron selectively to a base. I stopped by some other forums recently and got reading about epoxy granite DIY cncs - it's amazing what people are doing with new compounds. How stable is your fixture? That's not very much tool pressure so either the machine is really, really light, in which case you're poo poo out of luck, or your method for clamping the workpiece isn't doing the job. If you're using a vice try clamping it a bit tighter. Can't hurt to verify that the tool is tight in the collet as well. As far as feeds, .005 - .008 should be fine. Are you using a 3/8 end mill or an actual cutter like a Woodruff?
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Apr 13, 2017 13:29
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Mudfly posted:I had a small aluminium TIG wire piece in the vice on the back jaw as I'd seen in a video on the net when squaring up a block. I had the piece _very_ tight in the vice, but I did notice one parallel fall over like a domino after I was done. I remembered afterwards I saw the video guy lightly hammer the piece in the vice down onto the parallel. Maybe clamping is my issue. Yeah, you definitely want to tap the part down with a rubber mallet. Before you start the spindle up, reach down inside the vice and give the parallels a little push. They don't need to be rock solid, but you do want them to both be snug before you run it. I'd bet that will fix your issue.
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Apr 13, 2017 14:25
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Mudfly posted:Cheers I tried this, but the parallels just wouldn't stay put. I went ahead and milled anyway, after leaning like a gorilla on the vice. It can be a little touchy trying to get the part to sit flat on the parallels. If the vice is too tight, the part won't move when you hit it. So you kind of snug the vice up, tap the part until the parallels are flat with the part, and then tighten it the rest of the way. You can also have issues where the part can bounce back up off the parallels if you hit it too hard, so it can take some playing with. And you shouldn't have to crank the part down that hard, since you're not dealing with much tool pressure. Just so long as it isn't loose. That said, your finish is god awful and something is hosed up bad. Here's some things you can investigate. Is the table level and square? Is the vice itself level and square? Is the vice tightened properly to the table? Are the jaws in the vice tightened? When the part is tightened, do the jaws sit flush against the part on both sides, or is there a gap? Are the jaws all chewed up and not making good contact with the part? Are the parts bent, crooked, or not square? Does the end mill have corners broken off? Is it deep enough in that collet? Is it tight? Is the spindle hosed up? Do you hear any nasty noises when it's running? Does a tool spin perfectly around itself, or does it look like it might be wobbling side to side a bit? Volkerball fucked around with this message at 09:34 on Apr 14, 2017 |
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Apr 14, 2017 09:27
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Lmao. It happens.
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Apr 14, 2017 10:24
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Sagebrush posted:Good Lord. No, that particular error doesn't really "just happen," that's...next level loving up. I'm amazed it "cut" at all -- you were basically just friction-heating the material and shoving it aside. He learned something today didn't he? Lol. Playing with cheap tools and soft aluminum isn't going to irreparably gently caress anything up. But yeah, you're climbing a steep hill if you don't have someone you can work with to help you out, and this is but the first of many big no-no's you're going to learn about the hard way.
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Apr 14, 2017 13:26
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Rapulum_Dei posted:I wonder has anyone done repeatability tests on the cheap electronic calipers. I know AvE calls them out for being unreliable when the battery gets low but otherwise is it possible they're just as accurate in normal use? Fowlers are the absolute lowest I would go for digitals. I'd prefer starrett dial calipers over that though.
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Apr 21, 2017 09:17
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A Proper Uppercut posted:You really can't go wrong with Mitutoyo, we use these ones in the shop and they are solid, and under $100 https://www.amazon.com/Mitutoyo-Advanced-Absolute-Digital-Caliper/dp/B00WMKUUAQ These are great so long as you keep in mind that they are not coolant proof.
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Apr 21, 2017 11:40
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Rapulum_Dei posted:A friend who was a factory fitter told me about a trip he took to Japan when his company wanted to see if they could adopt the more efficient Japanese working practices to up unit output. More than that, it's lean manufacturing implemented correctly. Every machine shop I've ever been in has glaring, horrible flaws that cost the company god knows how much, and they simply don't have the skillset to identify and fix those problems. So poo poo just sits around and rots. It boils down to supply chain logistics and communication for the most part. American manufacturing is horrible at it, and I've watched companies throw way more money away over that than whatever you can gain from a couple seconds of cycle time by removing guards.
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May 8, 2017 20:16
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SwitchbladeKult posted:It isn't just manufacturing. Bad implementation due to poor planning and lack of communication basically describes all areas of American business. Even when a company has the people with the skills to identify and fix problems management usually tells them to blow. I don't doubt it.
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May 8, 2017 21:03
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CarForumPoster posted:I learned cam programming (CAM Works for Solidwoks 2007) on a VM1 in 2007 so they definitely do g code. Of course, probes aren't a magic bullet. They can be a bitch to deal with when the battery is getting low or they aren't functioning properly, they're expensive as gently caress and people will crash them, and there's all sorts of quirks with the spindle since it has to remain oriented through the whole probe process. It's still really nice, especially for having the ability to write programs that probe parts 100% to comp for variance in your parts and in loading. And it's generally quicker than using an edge finder. But it does introduce a lot of other problems, and there's been more than one occasion where I've gotten through with it and been like man I should've just touched a tool off on the part for Z instead of loving with all this for a half hour. One thing worth mentioning is that the haimer 3d sensor functions as a ghetto probe, and I've heard good things about it. So that might be more in your budget.
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May 28, 2017 07:04
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Fairly obvious, and I'm not trying to insult your intelligence, but one thing with through coolant to keep in mind is that depending on the layout of your coolant vat, you can have a lot of issues with pressure alarms that have nothing to do with programming. There's a screen in front of the pump that prevents chips from getting in, and it can get clogged with very fine chips pretty frequently. Depending on the machine and what you're running, that can need cleaning as much as once a day. It's also best to keep coolant levels as high as you can without it foaming over. We have one machine that will start alarming out with TSC when the coolant level drops below 3/4 of a tank, because otherwise, the pump will drink coolant significantly faster than it can being replaced. Also chip buildup anywhere in the tank can affect the flow of coolant from one side of the vat to the other, which can mean one side of the vat is full, and the side where the pump draws from can be inches lower when the pump has been on for a bit. So that's another culprit to look out for.
Volkerball fucked around with this message at 11:38 on Jun 10, 2017 |
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Jun 10, 2017 11:35
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Mudfly posted:I need to increase the size of a 17mm pulley ID to 19mm to mount on a motor. Can I just put the cylindrical pulley in my regular vice and drill/bore it out with the mill? I don't have any special fixtures for grabbing circular parts but I figure the forces if I go slow will be small. All you'd need is a V block between one jaw and the part so that you have 3 points of contact. You don't need to mill a set of jaws or anything for it if you're just running the one. If you just try to clamp it in normal parallel jaws, something bad is gonna happen. Volkerball fucked around with this message at 13:56 on Jun 13, 2017 |
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Jun 13, 2017 13:13
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You can toy around with using a slightly smaller drill that can spin freely inside the hole, or the 17, but you're right about the concept. Indicator works too. I'm not familiar with mm, but you'd generally use a reamer for this application, so I'd just be careful with feeding. Especially if it's steel.
Volkerball fucked around with this message at 14:12 on Jun 13, 2017 |
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Jun 13, 2017 14:10
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honda whisperer posted:Anyone recommend a good resource for learning nc programming? I got thrown in the deep end at work and I'm really feeling my lack of knowledge in this area. Check their catalogue and see. It'll tell you if they have prerequisites for the classes you want. There's also usually a one year program for a CNC programming certificate, so you could also look at getting one of those to have something to show for your schooling. What are you running? Mills? Lathes? And what brand of machine?
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Jun 29, 2017 01:03
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Can you fixture it at the angle the spiral is on so that cut will be parallel to the tool path?
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Jun 29, 2017 03:42
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| # ¿ May 12, 2024 12:30 |
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If the machine won't run with the "door" open, then you're good. The bigger issue would be people plugging in a -10. offset on Z instead of -.010, and non industrial machines can't usually shrug that off.
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Jul 6, 2017 07:09
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