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Mudfly posted:How can you make your own pulleys (small, like GT2 printer pulleys) at home? I have a rotary table & mill and I understand how to cut them like a spur gear but I don't know where to get the cutting bits. Spur gear cutters are readily available on ebay but I can't find pulley cutters. I realise you can make your own from HSS and attach it to a fly cutter but I don't know how to grind the HSS accurately - some of the radii in the GT2 pulley profile are really small, like 1mm or less. If you don't already have the kit to make something this persnickety, just buy it, or buy the closest equivalent and modify the project to accommodate it. Assuming you're a glutton for punishment and/or value ~the experience~ more than expediency- This gets really kludgy without a lathe, says the guy who's tried to make lathe tasks work on a mill with no rotary table. If you can set your rotary table on its side, you can cut the pulley groove with a really small ball mill, but if that's out you gotta get weird with it. Making a rotary cutter that'll cut that profile on that scale into the side of a part is probably beyond your means if you're not already zippy on the grinder. I've turned small things on my Taig mill in a pinch by sticking the stock in the spindle collet and putting an HSS bit in the vise and moving the table to engage the cutter but it's far from ideal and is definitely bad for the spindle- and you still have the cutter to work out. You can assumably buy radiused lathe bits of the radii you need commercially, but it'll be way more expensive than just buying the pulleys so why bother. What I'd do, if I were hellbent on making it work myself, would be to: -get a small HSS drill bit of the appropriate diameter; -stick it in the mill chuck upside-down, so only a bit of the HSS solid shank is sticking out of the chuck; -put some newspaper over the table to protect it and start the mill up; -use a Dremel with abrasive tool, diamond file/hone or beater bench stone to shape the end of the shank into as tidy a hemisphere as I could; -take the drill out of the chuck and, using that same abrasive tool, remove half of the ground sphere end to produce a flat radiused face with a crisp edge; -put my new mini radius cutter in the vise with as little stickout and as much support as is reasonably possible, and put the almost-finished pulley in the chuck with a purpose-made arbor or with the shank I left on it; -very carefully 'turn' the pulley groove as needed, maybe do a very light finishing pass with a general-purpose bit while I'm at it because single-setup concentricity is always nice I suppose you could also put that cutting bit in a crude 90-degree 'flycutter' made from some drilled-through round stock with a set screw installed and cut the groove with the flycutter in the spindle and the pulley set up conventionally on the rotary table. Would be easier than making a mandrel from scratch to hold the pulley stock, at any rate. ...even odds are that you'll just break the drill 'cutter' and waste a few hours of your life, but what's that thing they say about the journey being more important than the destination Ambrose Burnside fucked around with this message at 23:39 on Sep 24, 2017 |
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Sep 24, 2017 21:01
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shame on an IGA posted:Marry it to a hydraulic pump and become the envy of your log-splitting friends That does seem ideal
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Sep 24, 2017 22:37
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A Proper Uppercut posted:Theres a shop near me, my boss is friends with the owner. They have two of those Index machines. They are insane. I think they were like 2 million each? That sounds about right. They are fully sick, when I was running one 2015-16 we had a ± 12 ųm tolerance on a backworked feature and could hold that all day. Also fun this week was hearing about the maintenance guys at that shop broke one in such new and exciting ways the factory tech didn't believe them without pics. With enough effort, it is possible to trick the spindle carrier into winding itself and the hydraulics, and coolant lines, and cables two full revs instead of just one. shame on an IGA fucked around with this message at 23:54 on Sep 24, 2017 |
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Sep 24, 2017 23:51
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The Canadian dollar is up p high right now so i'm considering ordering a lathe to my Niagara Falls mailbox and driving it over the border home. Anybody have anything good/bad to say about the LMS mini lathes? I think the Sieg 7x14 is the only one I have the budget for atm, is there a cheaper/better source for that caliber of generic import mini lathe? Harbour Freight's options seem uncharacteristically pricey in comparison. Worth spending almost twice as much for the longer bed and brushless DC spindle motor of LMS' hi torque offerings? Any other good sources for mini lathes in the US that I've disregarded til now?
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Sep 25, 2017 18:38
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edit: i'm sure someone will be along to ban you presently (USER WAS PUT ON PROBATION FOR THIS POST)
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Sep 26, 2017 06:05
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Little fruity in here....
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Sep 26, 2017 06:09
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So I have a couple coils of very thick solid uninsulated copper wire, something like 1/4in thick, that I think is meant for gardening somehow. I'd like to use it to construct an antenna, but I'm not really sure how to straighten it out. It's pretty tough and hard to work with by hand, and the best I've been able to do manually is still kinda wavy and warped. Are there any secret tricks to getting wire like this decently straightened without special dedicated equipment?
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Sep 28, 2017 15:26
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Get two bricks and a propane torch, if it's work hardened from being coiled/bent you will need to anneal it to make it soft again. You could probably do it in a campfire if it's big enough. You don't need to work copper at heat, just heat it up, let it cool, then work it again until it gets too hard to bend again. If you want to pound out little dings or bends, a light-ish hammer with a flat/round face will do fine. Hell, a rock would work ok too. Use some sacrificial flat lumber (preferably something dense) to work against. E: if you can find some metal rollers with a v groove just build a little jig and run the wire between the rollers, that'll straighten it out too. Double edit:. VVV poo poo sorry, I was editing my reply to add this just as you did Slung Blade fucked around with this message at 15:53 on Sep 28, 2017 |
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Sep 28, 2017 15:50
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I don't know of any other way besides using a series of grooved roller dies that you feed the copper through. You might also need to anneal it first.
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Sep 28, 2017 15:50
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Ah didn't even think to anneal it, thanks! I do have a wide, flat hammer with heads coated in plastic / rubber stuff (it's not quite a rubber mallet but like it's cheap cousin I guess?) that I figure I could use to tap on it a bunch. As far as rollers go I don't have anything like that, though I suppose I could look around to see if there's anything I can use like that or get for cheap... Though I think I'll start with just the anneal + mallet approach and see if I can get it fairly straight with that. I'm not going to be making tons of them and It doesn't really need to be exact down to the millimeter or anything, just better than the absolutely terrible job I did by hand 
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Sep 28, 2017 16:03
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Copper is soft enough that you don't have to anneal it at all, it'll just make your job easier. I never anneal copper unless it's work-hardened enough that I can feel it getting "gritty" when deformed, I don't know how to describe it but there's a change in its ductility when it reaches the limits of its workability but before it starts cracking and shorting. If you've got a torch and don't mind the copper ending up darkened and oxidized, go for it. You may not even be able to anneal it without a good insulating setup or an oxyfuel-scale torch, though- copper is so heat-conductive that the whole body of the stock sucks all the heat from the work site. I need two propane torches working in tandem, plus patience, to anneal large sections of copper sheet properly- 20 ga. stock that would heat through in seconds if it were steel- because it draws away and radiates into the air so much heat. Anyways, you need an anvil or ersatz anvil (any level steel surface with some weight and backbone will do), ideally you'll have at least ~8+" of anvil working face running in at least one direction. You'll need that soft mallet and you'll also want a steel hammer with a slightly-rounded face and softened corners to avoid unwanted dings. Straighten as much of the rod as you can by hand or in the covered jaws of a vise. The vise can't do all the work because of springback but it's handy at this stage. Put the rod on the anvil and locate the biggest deviation from the bar's desired central axis- the biggest single bend. You can find it by rolling and moving the stock over the anvil and seeing the point it's highest off the plate at. Knock that point down with the soft hammer. Continue that process along the bar, knocking down smaller and smaller bends. The rod will start looking pretty straight, but if you roll it between your fingers you'll see the remaining eccentricities stand out. At some point the soft hammer will stop working because soft hammers don't deform and displace metal, which is what you need for the smallest or sharpest bends. Switch to the hammer and do as before- deform the copper as little as necessary ot get it down flush with the plate. Eventually you'll be to the point where you're rolling the bar in your fingers and striking the rod gently all along its faces- fining-up blows that even everything up. Congrats, now you've got a straight bar with tight enough concentricity that you can turn it on a lathe pretty readily and which registers as perfectly straight to the eye.
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Sep 28, 2017 16:29
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Ambrose Burnside posted:Copper is soft enough that you don't have to anneal it at all, it'll just make your job easier. I never anneal copper unless it's work-hardened enough that I can feel it getting "gritty" when deformed, I don't know how to describe it but there's a change in its ductility when it reaches the limits of its workability but before it starts cracking and shorting. If you've got a torch and don't mind the copper ending up darkened and oxidized, go for it. Thanks for the details, I guess I'll see if hammering works without annealing and go from there. I think I should be able to anneal it anyway if I have to, it's not going to be more than a meter or two long and pretty thin so I don't think it can radiate away heat as fast as a sheet would. The spool I opened is already pretty oxidized since I opened it a while ago, so I don't think blackening it more will make much of a difference either.
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Sep 28, 2017 17:01
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Once it's straight you can scrub it to get most of the oxidation off. Depending on how long the antenna is going to be and if you want it shiny then you can pickle it. For short elements a Pyrex glass pan or a croc pot works. For longer stuff you can seal up the end of a pipe, I think pvc is fine but I haven't ever done it myself, fill it and use something to keep the solution warm. Pickle can be made at home, it's mostly just hydrochloric acid and some additives, Pool chemicals. If it's going to be outside plating it would be ideal, but a light coat of clearcoat or epoxy will also do to reduce corrosion for hobby purposes. Paint or clearcoat might have some dielectric impact that will change your gains.
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Sep 28, 2017 17:34
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I've watched all of AvE, Abomb79, This Old Tony, Clickspring. I've watched a good amount of Ox tool and Tubalcain. What other channels do you all watch? Anything close to AvE and ThisOldTony?
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Sep 29, 2017 20:27
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Applied Science is pretty cool,
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Sep 29, 2017 21:21
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I got my lincoln weld pak 100 working, and drew a handful of beads! Fluxcore is very smoky. How bad is it to breathe in burnt flux smoke? I'm gonna set up a fan, and I've been wearing a filter mask, but should I switch to my full respirator?
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Sep 30, 2017 01:14
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rawrr posted:Applied Science is pretty cool, Second. Even his 5+ year old poo poo is still really cool and well done. Tubalcain can be stuck up his own rear end a lot of the time.
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Sep 30, 2017 05:35
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Leperflesh posted:I got my lincoln weld pak 100 working, and drew a handful of beads! Fluxcore is very smoky. How bad is it to breathe in burnt flux smoke? I'm gonna set up a fan, and I've been wearing a filter mask, but should I switch to my full respirator? It's not great for you -- but it's more irritating than toxic. Welding in a well-ventilated area (garage with the door open) should be plenty. Use a P100/OV respirator cartridge if that's not enough.
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Sep 30, 2017 06:48
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Who wants to watch a 9-hour NASA training seminar about bolt selection!!??! http://www.fastenerjournalstore.com/store/videos.htm Haha "Split lockworshers have been demonstrated in every test we've ever run to provide exactly the same resistance to loosening as plain flat worshers at full fastener torque, with the bonus of damaging the underlying surface. I got in a lot of trouble once for writing that split worshers are useless in a fastener trade magazine and the fellow that wrote in the month after owned a split lockworsher factory and wasn't too happy about me calling his product worthless. His product is worthless." shame on an IGA fucked around with this message at 16:09 on Sep 30, 2017 |
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Sep 30, 2017 15:49
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shame on an IGA posted:Who wants to watch a 9-hour NASA training seminar about bolt selection!!??! Unironicly yes. Will be a nice break from electrical connector selection. Ask me about mil-std circular connectors
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Sep 30, 2017 15:50
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Field wireable M8 3-conductor for life. The little bitty terminal blocks are jewelry
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Sep 30, 2017 16:00
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M_Gargantua posted:Unironicly yes. Is there anything significantly better bang for the buck than MIL-DTL-38999 for applications where I don't have to meet any cert but want durability, lightweight, and weatherproof-ness?
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Sep 30, 2017 16:58
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Metal Geir Skogul posted:Second. Even his 5+ year old poo poo is still really cool and well done. Tubalcain can be stuck up his own rear end a lot of the time. For sure, Tubalcain has his moments where I feel like my eyes are gonna roll themselves out of my skull. But he's got some Old Man Knowlege which is what I like to watch for. Definitely will be checking out the recommendation, thanks
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Sep 30, 2017 17:11
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For more machining oriented stuff Stefan Gotteswinter is also pretty good. Also, https://www.youtube.com/user/dgelbart/videos is a treasure trove
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Sep 30, 2017 17:28
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Yeah, the old man knowledge is the creamy nougat of Tubalcain. Just a shame it's wrapped up in him. Still good watching, especially for certain projects he does.
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Sep 30, 2017 21:29
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mekilljoydammit posted:Is there anything significantly better bang for the buck than MIL-DTL-38999 for applications where I don't have to meet any cert but want durability, lightweight, and weatherproof-ness? Not really. 28840s are the other common one and they tend to be a step up in price and accessory selection. Anphenol (Tuchel, LTW and PCD branches, stupid mergers), TE (Under Deutsch label), and Glenair all make solid non-certified circular connectors that tend be to about half the price, but are effectively the same thing. The benefit of ordering 38999's is how modular they are, and how theoretically you can salvage old ones from any brand and they should fit together, more or less.
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Sep 30, 2017 22:27
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rawrr posted:For more machining oriented stuff Stefan Gotteswinter is also pretty good. I have one question - I have access to a large surface plate - can I use scraping to true up surfaces for mounting cnc rails? And other projects requiring long flat sections? I can mill but I can't afford / have no access to a surface grinder, I was hoping scraping could be used in lieu of it. Milling then scraping ~500mm long sections.
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Oct 1, 2017 12:07
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If you're mounting rails I think you can get away with just face milling the surface: https://www.youtube.com/watch?v=K9UA9ZRFwWU&t=1003s Otherwise, he also has a 3 part video on exactly what you're thinking of doing. Looks really time consuming and involved: https://www.youtube.com/watch?v=RjwKQCiDgBQ&t=260s rawrr fucked around with this message at 15:43 on Oct 1, 2017 |
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Oct 1, 2017 15:41
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b/c frustration over a lack of small indexable end mill options has come up in here before- ive never seen anything with 2+ inserts in Imperial sizes with a shank dia. <.5", which is an issue for smaller mills n particularly anything using ER16 collets, but looking at import aliexpress/banggood et al options you can get double-insert face mills down to 10mm dia. pick up a 10mm collet on the cheap while you're at it and you're off to the races. I'm looking at a 10mm end mill + collet + inserts for, like, ~$35 CAD with tracked shipping from AliExpress. Might be a piece of poo poo waste of money, but... what if it isn't???
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Oct 1, 2017 18:30
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I do love me Ave. Spent some time getting caught up and thought his call out of tool reviews was pretty well done. Particularly when he had the video of that wrangler dude slobbering over a Milwaukee case. Ave is like the Consumer Reports of YouTube vids. 
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Oct 1, 2017 20:15
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I'm designing a drill jig that has to allow drilling and then reaming holes without moving the part. Any clever or faster alternatives to just rolling with swapped-out SF bushings?
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Oct 1, 2017 21:30
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Multiple holes in the same plane? Put all the bushings in a plate with some locating pins and make two, swap all the bushings at once instead of one by one
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Oct 1, 2017 21:42
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shame on an IGA posted:Multiple holes in the same plane? Put all the bushings in a plate with some locating pins and make two, swap all the bushings at once instead of one by one Yep- that's a little more straightforward than what I was thinking, and can also deal with the bushings needing different clearances from the part in a marginally-more-interesting way than just using different-length stock bushings. Thanks~ Ambrose Burnside fucked around with this message at 22:16 on Oct 1, 2017 |
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Oct 1, 2017 22:14
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Speaking of scraping, this would be really interesting if a Japanese speaker could provide a translation - https://www.youtube.com/watch?v=t0gg9z4gG3A .
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Oct 2, 2017 02:41
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Mudfly posted:Speaking of scraping, this would be really interesting if a Japanese speaker could provide a translation - https://www.youtube.com/watch?v=t0gg9z4gG3A . I don't know what they're saying but they are some talented fuckers. Anyone know how granite surface plates are made to tolerance? Since you can't scrape it (or can you?) how do they get them flat?
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Oct 2, 2017 20:41
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Ambrose Burnside posted:I'm designing a drill jig that has to allow drilling and then reaming holes without moving the part. Any clever or faster alternatives to just rolling with swapped-out SF bushings? Do you actually need the bushing on the reamer, or do you just need the bushings out of the way to ream? A couple weird ideas spring to mind. Get reamers and drills with the same shank size, and then get the flute length and bushing length sized so the shank engages the bushing before the flutes touch the part. Essentially pilot the shank rather than the flutes. Whether that's acceptable depends on the required flute length and tolerances. If the flute length is long enough that it can flex independent of the shank then no good. May also require custom tools, depending on the sizes you can get. Alternatively, the reamer and drill both have a bushing that floats on their flutes. I'll leave retaining that as an exercise for the reader. Then the bushings in the drill jig guide that bushing. It does also hurt tolerances, since now you've got two clearances rather than one.
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Oct 2, 2017 22:48
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M_Gargantua posted:Not really. 28840s are the other common one and they tend to be a step up in price and accessory selection. Anphenol (Tuchel, LTW and PCD branches, stupid mergers), TE (Under Deutsch label), and Glenair all make solid non-certified circular connectors that tend be to about half the price, but are effectively the same thing. Modular THIS https://cdn.glenair.com/superseal/pdf/c/233_340.pdf
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Oct 3, 2017 02:54
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Just joined the Chesapeake Forge guild in Maryland. Went to my first open forge night and everyone seemed really cool. People were friendly and chill, saw a lot of cool stuff get made. Plus where I'm an ~ experienced smith~ I don't have to take the intro class, although I offered. Seemed like everyone was willing to help out and offer suggestions, so it looks like I finally get to work with other smiths!
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Oct 3, 2017 04:38
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One of the guys at the residential school I went to grabbed a surface plate to do his folded edges on the sheet metal project we had to complete. Thankfully the tutor noticed before any harm was done to the plate. I've always used cast steel slabs for that sort of work but you normally need to salvage them from the wood workshops where they get used as weights.
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Oct 3, 2017 09:24
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Pshaw. Only two keyway options.
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Oct 3, 2017 12:07
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