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Holy fuckin fast replies batman!! Thanks for all the info, my "plan" was to grind and file the pointy bits and then heat with an oxy-acetylene torch till it's "red-hot" for an indeterminate length of time and then......... Probably just dump it in a 5 gallon bucket of water at whatever ambient temperature it (the water) happens to be at the time until it's cool to the touch. Glad to know about the temperatures, I forgot I have an ir thermometer. Hopefully it will read high enough temps.
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Aug 30, 2023 15:04
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An easy check is to have a magnet handy. Steel loses magnetism around ~1420F and will also usually gain (some) hardness if you quench after that point. If you let it slowly cool instead of quenching, the steel will anneal and become softer and relieve alot of stresses and work hardening from cold working. In theory, you could heat the pipe to nonmagnetic and slow cool it to soften it a bit and heat your toothed thing and quench it to harden it. Not sure how much basic iron pipe will really soften tho as I think it's formed hot and probably doesn't have much work hardening. Similarly, even mild, low carbon steel will be hardened somewhat by heating and quenching, but not nearly as much as a high carbon steel.
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Aug 30, 2023 15:15
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All of this is cool and interesting butAmbassadorofsodomy posted:Item is going to get dropped in to some SCH40 pvc pipe and will hopefully (via the teeth) wedge itself in there so the pipe can be pulled from the ground. you don't have to harden the teeth to have them bite into plastic. I'd just cut them and send it
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Aug 30, 2023 15:55
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Oh yah I saw schedule 40 and missed the pvc part. Yeah just send it, none of what we said is worth your time. E: also is it possible to just bolt a bar into the pipe? Seems way easier to hook it out with a fixture than hoping something will cut into the pipe body enough to gain traction. threelemmings fucked around with this message at 15:59 on Aug 30, 2023 |
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Aug 30, 2023 15:56
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Sagebrush posted:All of this is cool and interesting but
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Aug 30, 2023 16:08
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pvc pipe is already non-magnetic. 
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Aug 30, 2023 16:11
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Sagebrush posted:pvc pipe is already non-magnetic. 
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Aug 30, 2023 16:14
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yeah sorry in retrospect i recognize the joke but i'm still waking up and groggy
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Aug 30, 2023 16:28
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While we're joking about it, real talk about pipe: be extremely cautious when quenching hot sections. It will launch blobs of steaming water with a sound like a potato cannon. If youre in oil the oil will shoot out on fire.
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Aug 30, 2023 16:37
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threelemmings posted:Oh yah I saw schedule 40 and missed the pvc part. Yeah just send it, none of what we said is worth your time. Its for pulling test wells out of the ground, Sometimes they have threads on the top in which case I have short sections of the same threaded pipe with a hole drilled in to it that I can spin on there and use a metal hook to pull it, but most of the time thats not the case. We've tried various contraptions and methods over the years with varying amounts of success but I want to try something different. Theres lots of commercially available pullers for larger size (4+ inch) but I have yet to find anything available and good for 2 inch pipe. And don't get me started on that for 1 inch pipe.
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Aug 30, 2023 17:23
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Maybe cut some discs out of thin 1075 spring steel. Shape the disc like the flower petals on a daisy, with a slightly larger OD than the ID of the plastic pipe. The discs have a central hole to attach them to a length of threaded rod. So you have this threaded rod with a half-dozen of these discs on the end, maybe spaced out a little with washers. When you shove it into the plastic pipe, the 'petals' of the discs bend back, letting them slide into the pipe ID. When you pull back on the threaded rod, the edges of the petals will dig in to the walls of the pipe and lock in place. Downsides are the laser-cut discs will cost $2.50/ea for 1.5" ID pipe, and you will need to cut/destroy the pipe to get your tool out. Also this might turn out to be a lovely idea that doesn't actually work, dunno.
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Aug 30, 2023 18:09
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ryanrs posted:, and you will need to cut/destroy the pipe to get your tool out. Also this might turn out to be a lovely idea that doesn't actually work, dunno. I didn't read the rest of the conversation in great detail, but this reads to me as, "stick weld the anchor/pull device to the well pipe"
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Aug 30, 2023 18:48
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Hadlock posted:I didn't read the rest of the conversation in great detail it's pvc pipe
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Aug 30, 2023 19:02
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replace "stick weld" with "jb weld SteelStik" I'd be tempted to just tap it and then screws something into the threads. Three inches of threads ought to be approaching the tensile strength of the main pipe Hadlock fucked around with this message at 19:15 on Aug 30, 2023 |
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Aug 30, 2023 19:13
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here's what i picture maybe also cut some splines on the pipe before splitting it so the teeth are interrupted, which should increase their bite pressure
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Aug 30, 2023 19:36
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threelemmings posted:Oh yah I saw schedule 40 and missed the pvc part. Yeah just send it, none of what we said is worth your time. obsolete bicycle technology seems like the perfect tool for this job, cut a spacer and a threaded wedge at an angle and tighten a bolt through it like an old school handle bar stem 
shame on an IGA fucked around with this message at 19:40 on Aug 30, 2023 |
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Aug 30, 2023 19:37
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Thanks for the ideas, I'm trying to do this without having to resort to a machine shop (like the threaded wedge device). The pipe doesn't matter, its not *supposed* to be re used afterwards, though some cheap fucks do.
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Aug 30, 2023 19:58
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Can you just buy a tap that would thread into it and weld a ring on the end? Use a pipe through the ring as a tap handle.
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Aug 30, 2023 22:27
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I am late to the heat treatment party but one thing kind of glossed over which I think is good to understand because it puts all the rest into context, is why heat treating can harden steel. Steel is an alloy of iron plus other chemicals. Even "wrought iron" which in modern times is also called "mild steel" has some impurities in it which makes it an alloy, but modern steels are typically very carefully controlled and exactly how much of what is in them is very consistent and well understood. When you heat the steel there is a critical temperature above which the atoms and molecules of alloying substances within the steel matrix can migrate around. Yes, this happens within the still solid metal, which is kind of cool to think about. If you let the steel then gradually cool, crystals begin to grow and form within the matrix. The slower it cools, the longer those crystals have to form. The shape of the iron crystals and the matrix of crystals of different alloying compounds within the steel - grain size, amount, arrangement, etc - determines the physical properties, where hardness and toughness are kind of opposites. That is, the harder the metal, the more brittle, vs. the tougher the metal, the softer. Exactly how tough/brittle/ductile/soft etc. you want your final product determines both what alloy you ought to pick and what heat treatment you want. You can get basic carbon steel - that is, iron alloyed with something between at least like .25% and no more than 2% carbon - to achieve a very hard (but quite brittle) structure by heating it to that critical temperature (called "austenitic" because the iron at that temp changes from a cubic to a face-centered crystalline form called austenite) and then freezing the steel to keep the crystals from growing larger than desired or from changing back to cubical "ferritic" steel via slow cooling, by quenching it. The quenching material can be water, oil, or even just cool air; each results in a different speed of cooling. However, quenching "too quickly" can cause (especially thicker) pieces of steel to crack, because the surface in contact with the quench cools faster and contracts while the interior is still very hot. This is why there's all kinds of lore, going back literally thousands of years to the dawn of the iron age, about what is the right thing to quench what into to get the right result. Another factor is post-quench heat treating, most typically tempering. You "temper" to actually reduce the hardness of your result, typically because after quenching the metal is so brittle that it will spall, chip, or break upon use. In knifemaking, for example, quenching a carbon steel in water or oil will leave you with a "glass hard" edge that is hard as gently caress but will chip with any use. So you bring the metal up to a well below austenitic temperature, allowing a little bit of crystalline growth and relief of pressure, and then quench it again, to avoid over-tempering it. OK. So why do you want to harden your tool? You should do so only if it's necessary, because part of the deal is you are getting sharp bits that are more brittle and fragile in exchange for your hardness. Secondarily, will it harden at all? The less carbon, the less result. Another reason to do a heat treatment is to anneal, which some folks mentioned, but unless you know you need to relieve some work-hardening stresses with an anneal, if you don't need hardening you shouldn't do a quench. And thirdly, if you do quench, and if there's any significant amount of carbon, you may need to temper as well. Leperflesh fucked around with this message at 22:42 on Aug 30, 2023 |
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Aug 30, 2023 22:38
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Ambassadorofsodomy posted:Thanks for the ideas, I'm trying to do this without having to resort to a machine shop (like the threaded wedge device). What about a speargun tip? 
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Aug 31, 2023 15:09
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fins posted:What about a speargun tip? wow they make unthreaded toggle bolts?
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Aug 31, 2023 17:04
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Is 6061 aluminum or O1 tool steel (for example), going to be the exact same composition regardless of where you order it from, or do some foundries produce higher/lower qualities of material?
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Aug 31, 2023 18:59
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Skunkduster posted:Is 6061 aluminum or O1 tool steel (for example), going to be the exact same composition regardless of where you order it from, or do some foundries produce higher/lower qualities of material? Any reputable retailer (Not AliExpress/BangGood for example) is going to have the same poo poo. You can also request material certs. The only time I've ever seen a material related issue is when it comes from a 3rd world source, without certs, or traceability.
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Aug 31, 2023 19:03
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Like, if you are working in a scientific lab and want 6061 that is certified to be precisely and exactly the right thing down to parts per million you will need to get certs and they will only guarantee a certain narrow range of percentages of alloying metals etc. For any other purpose, any US-based metal retailer is going to be offering functionally identical metal.
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Aug 31, 2023 19:09
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Oh hello, may as well jump on the alloy and tempering chat. I've been tirekicking a project that needs a flexspline for a few years. My best understanding is that SS 304 is the material to use. Additionally, my understanding is that it will be nonmagnetic, and then when I machine it, it will probably work harden, and then become magnetic. And then I need it slightly springy still, so I will need to temper it, in which case it will be nonmagnetic again. Metal Supermarkets lists SS304, and then when I requested it, this is what's listed on the invoice:  It's a huge pain to lathe. And it's magnetic afterwards.  For tempering, my understanding is that I need to get it to 1850-2050F in a hydrogen oven. And then air cooling slowly. Which, lol, I don't have, I'm not doing that. I do have a regular heat treating oven, though. So what's the worst that can happen.  It's this:  I've never seen stainless steel oxidize before. So anyway, I tried it again, this time with wrapping the pieces up in steel foil, with a little bit of wood to try and pull all the oxygen out. This was a bit of a hail mary, and it didn't work. It's possible it could have maybe worked, but I hosed it up? Idk the foil was sharp as hell and I bled all over it too  This is a pretty meandering journey over about two years and it's pretty clear I have no idea what I'm doing. If there are any suggestions, I'm open to it.
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Aug 31, 2023 21:28
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The exact composition is going to vary, but as long as it's within the ranges in the specification it shouldn't be functionally different. Like A2 tool steel might have between 0.4 and 0.8 %mass manganese and 4.8 and 5.5 %mass chrome.
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Aug 31, 2023 21:30
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A513 is a normal rear end carbon steel usually used for low-load tube structures, and is not 304 stainless. They shipped or you ordered the wrong thing, sorry.
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Aug 31, 2023 21:46
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meowmeowmeowmeow posted:A513 is a normal rear end carbon steel usually used for low-load tube structures, and is not 304 stainless. That was one of the many thoughts I had. I certainly know what I told them, but they also are extremely casual about the poo poo they actually write down, I've noticed.
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Aug 31, 2023 22:06
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Yooper posted:Any reputable retailer (Not AliExpress/BangGood for example) is going to have the same poo poo. You can also request material certs. The only time I've ever seen a material related issue is when it comes from a 3rd world source, without certs, or traceability. Okay thanks. I don't do enough metalworking at this point for it to be an issue, but I was curious for future reference.
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Sep 1, 2023 02:26
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ante posted:That was one of the many thoughts I had. It's kinda a pain with them at times, the website often doesn't show stock correctly or pricing will be funny but depending on who you get on the phone they may make weird substitutions and stuff. 304 to 513 is a big one though, I've at least always had them double check something is ok if they're trying to sub something on hand for something they'd have to order.
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Sep 1, 2023 20:15
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So, brakes for bending metal - which names correspond to which type? I see the terms getting thrown around interchangeably (finger, press, box, pan) and nobody I've talked to agrees on which type is which. Is a finger brake just any kind that uses finger-shaped mandrels? Box or pan just refers to any variety that can make these shapes, right? Is a bending brake a specific type, or just any type that can perform bending? Is press specifically hydraulic press or any kind of actuation?
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Sep 5, 2023 19:11
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HolHorsejob posted:So, brakes for bending metal - which names correspond to which type? I see the terms getting thrown around interchangeably (finger, press, box, pan) and nobody I've talked to agrees on which type is which. Press brake means that a mandrel presses the metal into a die, usually hydraulically but also servo controlled. Pan-Box-finger means it's being bent over the fingers / tool edge. Watching a skilled CNC press brake is like magic. But watching some retired sheet metal dude work a manual brake is also amazing.
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Sep 5, 2023 19:22
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Yooper posted:Press brake means that a mandrel presses the metal into a die, usually hydraulically but also servo controlled. Pan-Box-finger means it's being bent over the fingers / tool edge. I am a not retired sheet metal dude, and watching me work the break is so not amazing. That's why I work out in the field.
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Sep 5, 2023 23:24
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Yooper posted:Press brake means that a mandrel presses the metal into a die, usually hydraulically but also servo controlled. Pan-Box-finger means it's being bent over the fingers / tool edge. I believe you, and yet...  e: I need real advice. I want to make a flange-mount to foot-mount adapter for a motor. I've got a design worked up in solidworks, most of it's pretty straightforward, but the hard part is cutting a roughly 4.5" hole in hot-rolled steel to center on the motor's flange. How would you do this in a home shop? I don't have a torch or plasma cutter. Was considering this circle cutter in my drill press, though reviews are mixed.  HolHorsejob fucked around with this message at 05:20 on Sep 6, 2023 |
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Sep 6, 2023 04:45
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https://www.homedepot.ca/product/milwaukee-tool-4-1-2-inch-hole-dozer-bi-metal-hole-saw/1001179615
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Sep 6, 2023 11:49
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HolHorsejob posted:I believe you, and yet... I stand corrected! I guess it's any brake with fingers.
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Sep 6, 2023 12:08
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HolHorsejob posted:e: I need real advice. I want to make a flange-mount to foot-mount adapter for a motor. I've got a design worked up in solidworks, most of it's pretty straightforward, but the hard part is cutting a roughly 4.5" hole in hot-rolled steel to center on the motor's flange. How would you do this in a home shop? I don't have a torch or plasma cutter. Was considering this circle cutter in my drill press, though reviews are mixed. Before I had a plasma cutter, I would have done that using a jig saw with a metal blade. Lay it out, drill a hole close to one edge to start in, and go to town. Wear ear plugs. One thing is that, as drawn, that motor bracket will be pretty floppy. (at least for any steel thin enough to bend in a home shop) I would weld or bolt some braces to triangulate it.
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Sep 6, 2023 17:17
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just clamp the sheet metal to your rotary table and mill it out imo
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Sep 6, 2023 19:59
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That hole saw I suggested a few posts ago is a pretty awful idea.
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Sep 6, 2023 21:51
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Ambassadorofsodomy posted:That hole saw I suggested a few posts ago is a pretty awful idea. You clamp that hole saw to your workpiece as a guide for your plasma cutter. 
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Sep 6, 2023 22:04
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