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Solder it in.
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Feb 1, 2020 18:28
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e: misread
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Feb 1, 2020 18:29
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Here in the northeast, there are always mills for sale for astonishingly cheap. Heck, often free. Once you realize that you will have to pay a rigging company $500 just to move the thing to the side of the road, lots of people suddenly start to negotiate on price. I've found mills for sale that come ready to go, often with chucks, tooling, and working DROs. Also, look for a makerspace. My makerspace has two mills, multiple metal and wood lathes, a CNC plasma, and a 5 axis CNC mill, along with so much tooling that the intern is still going through all of it. I was able to teach myself the basics of machining by asking some of the more experienced members, and I've made a few bucks making one off parts or small projects.
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Feb 2, 2020 14:33
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As it turns out, it's always easy for me to talk myself into new tools, so ordered a wobble broach.
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Feb 5, 2020 04:24
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mekilljoydammit posted:As it turns out, it's always easy for me to talk myself into new tools, so ordered a wobble broach. Funnily I have this same problem I'm changing jobs in a few weeks and have about a month's annual leave accrued (in Australia any leave entitlement except sick leave gets paid out when you leave or are fired), so when I leave it's at the end of the pay cycle and I'm looking at a looming ~9k payday and wondering what I can get (within reason of course) as I know my new job is fortnightly pay so within 2 weeks I'd start being paid full salary again My mind is on either a Tormek sharpener or an 84 engineering 2x48" belt grinder. Also it does vary as I am moving into my own place after share housing for 10 years so I'll need to buy a few things, but overall I think I'm a little overexcited for the prospect of having a ton of extra money for nothing
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Feb 5, 2020 05:17
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Been looking at the gear meshing in my milling machine, the vertical spindle is too loud and it's not the spindle itself. It's likely the meshing of the gears. When I had everything apart I noted two shim washers of .5mm behind the gear in the picture below, previous owner or factory setup I do not know. I took a pattern:   Not a good pattern. Attempted to remove one .5mm shim and got a better pattern. But too high on the teeth and the noise was unchanged.   I ordered a bunch of shim washers of 0.2mm and I tried a bunch of setups, 0.8mm seemed to pattern the best but still high, still loud and the spindle also felt sloppy. I decided I needed to see what it looks like inside and stop guessing. I removed the spindle from the vertical head casting and looked inside. This is with the gear shimmed 0.8mm, look at that backlash. https://www.youtube.com/watch?v=joV7tnDG9Qc And 1.8mm of shims, I tried 2mm but that would not turn. A lot less backlash but still not a good setup. https://www.youtube.com/watch?v=lAaF0oVXIHk The clicking noise that I hear when rotating by hand, which becomes a loud noise at high speed is still there. To me this looks like the gear to the left, which sits over the vertical spindle and drives it, is too high. it needs to come down, and as it comes down the other gear needs to move away as well. but it's clear that both gears need to be adjusted at the same time in order to get them to mesh correctly.  I think the bottom of the ring gears lower edges are impacting on the bevel gear teeth. And I think these marks (red arrows) are an indication of that. So I have ordered more shim washers for this gear and I will be bringing it down, it looks like it could need to go down quite a bit. The grease pattern above also tells a story of the gear not making optimal contact. I wonder if the gear was shimmed from factory and was lost by the previous owners because this was quite a bad setup, no way Deckel let it out in the world like that.
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Feb 11, 2020 08:48
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His Divine Shadow posted:Words. Can you explain what you mean by patterning the gears? It's not a term I've heard used before or a process that I'm aware of
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Feb 13, 2020 02:33
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McSpergin posted:Can you explain what you mean by patterning the gears? It's not a term I've heard used before or a process that I'm aware of You spread some yellow lead on the gear faces and spin them around; the areas where the lead gets smudged off are where the gear teeth are contacting. You ideally want the contact patch to be centered around the middle of the gear tooth because that's how they're designed to mate, and if they're not ideally you need to shim stuff to get there.
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Feb 13, 2020 02:48
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You put some bright colorful grease on the opposing gear, mate everything up, spin it, and then disassemble to see where contact is and isn't being made between the teeth.
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Feb 13, 2020 02:48
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I thought that may have been the answer, but just wasn't 100% certain. Cheers!
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Feb 13, 2020 03:51
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I did it when I put a limited slip diff into my car and changed the final drive ratio. It's tedious and takes forever but it's pretty cool once you've done it and understand how gears mesh.
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Feb 13, 2020 06:09
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I see the question was answered pretty well already so I will just link to a youtube video showing it. https://www.youtube.com/watch?v=dAqAqODmcj4&t=1461s
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Feb 13, 2020 10:23
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I grabbed this off the side of the road (our neighbor puts out things for free and I'm their best customer) I was thinking of making an arc furnace in the same vein as this https://www.youtube.com/watch?v=VTzKIs19eZE&t=366s and I'm comfortable with my fabrication skills but I'm not as confident with the electrical part. Ideally I'd like to just buy a "module" so to speak that can power the device and I come up with a way to load/unload the chamber and remove/replace the carbon electrodes. Is there something I can buy like maybe a cheap 240v welder from Harbor Freight that could power this with minimal rewiring? Like this https://www.harborfreight.com/225-amp-ac-240-volt-stick-welder-69029.html LegoMan fucked around with this message at 05:40 on Feb 18, 2020 |
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Feb 18, 2020 05:21
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Hey y'all, I was over in the DIY random question thread and had a question, but was suggested I bring it here:black.lion posted:Aye y'all, got married recently and bought my groomsmen pewter flasks from the UK (living in the US) as gifts. Apparently they got dropped in shipping, as two of them have tiny tiny holes in the corner that leak when filled. The holes are so small you can't see them, you have to put liquid in and let a tiny droplet pop out to locate the holes. But they exist. There was some discussion in the thread but no definitive answer. How should I go about repairing these tiny holes in these pewter flasks? TIA!
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Feb 20, 2020 14:14
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black.lion posted:Hey y'all, I was over in the DIY random question thread and had a question, but was suggested I bring it here: There's at least one dude here who works in pewter (I think...) so I'll let him chime in on the solder part. If you know exactly where the hole is you could just use your soldering iron to fuse the surface. You won't get any penetration with pewter solder anyhow. The difficult part will be knowing where the crack starts-stops. YouTube returned an interesting hit.   https://www.youtube.com/watch?v=OgAJcSzg6Vs&t=334s If ever I was going to trust random internet dude, this would be the one. At the 5:30 mark or so he busts out a soldering iron and glides it along the surface, that is what I'd do. Probably just a pin hole. I wouldn't use epoxy but I also wouldn't worry about it. It's already inside of virtually every aluminum can that holds beer. So if you drink beer, your drinking beer in contact with a harmless and inert plastic.
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Feb 20, 2020 14:31
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Aye thanks for the vids! I'll take a look when I'm home and I can listen with sound.Yooper posted:If you know exactly where the hole is you could just use your soldering iron to fuse the surface. You won't get any penetration with pewter solder anyhow. The difficult part will be knowing where the crack starts-stops. As for this bit, my plan was to put a little water in the flasks, shake 'em around a bit til a drop or two starts to come out, and then place a little circular sticker around the area to mark it (like the little sticker circles you use to repair holes on a 3-hole piece of notebook paper) for repair. But I've never soldered anything in my life so maybe there's a better way or that's a dumb idea? I'm comfortable using torches (use them in the kitchen and in other applications) just my first time soldering.
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Feb 20, 2020 14:45
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Can you actually drink out of pewter stuff? Dumb question, obviously you can, but I'm talking, like without health risks? Isn't pewter a mix of tin and lead?
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Feb 20, 2020 19:51
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Pewter USED to be mixed with lead, but nowadays it is safe to drink out of! For flasks its nice vs. titanium or steel bc it doesn't leave a metallic taste in the spirit, so you can put nice scotch etc in there and wont' ruin it or change the flavor at all. But pewter being p soft the flasks get dinged and scratched easily (which makes them look cooler imo) and, apparently, sometimes you have to patch a tiny hole bc international shipping 
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Feb 20, 2020 19:54
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How long ago is USED TO? Curious because I've got a few Tankards from My parent's wedding, circa 1968. Wouldn't mine drinking some ale from them if I'm not going to get me some lead poisoning.
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Feb 20, 2020 19:59
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According to Wikipedia, 1974, sorry bud  : but that's English pewter so if yours isn't English (is there another kind?) then I have no idea.
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Feb 20, 2020 20:09
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wesleywillis posted:How long ago is USED TO? black.lion posted:According to Wikipedia, 1974, sorry bud That's only regarding lay pewter, which you wouldn't make a tankard out of. Short version: your tankards are fine to drink out of. Long version: Any pewter made in the past century is unlikely to contain much if any lead, because lead has been undesirable for food service pewter items for much longer than you'd expect. Lead hasn't ever really been considered an acceptable major alloy component for the finer grades of pewter used for holloware/tableware, at least in the particularly well-documented world of English whitesmithing, which was represented by guilds going back to the medieval period. Lead is a cheap bulking agent with good working properties and was commonly used in large proportions in 'lay pewter', the cheapest and softest alloys favoured for cheap castings like votive objects. It's still used for that today. To improve the hardness and food-safeness + reduce the ease of tarnishing of a pewter alloy, you must limit or eliminate the lead component, and servingware must be quite hard to limit crushing/denting etc in use, so even without the toxicity of lead in mind, there has always been a strong impetus towards high-tin/low-lead pewters for functional food-contact goods That being said, if a tankard alloy isn't outright lead-free it may contain a few percentage points of lead to improve its casting/mechanical qualities. This is basically a non-issue for occasional use. Alcoholic drinks aren't typically acidic and aren't prone to leaching stuff from the vessel, and the length of contact for a simple tankard makes the leaching over time negligible. Recall that crystal wine glasses/decanters also contain a non-negligible amount of lead, and people rarely worry about that. My only concern with drinking from pewter comes with flasks, specifically because that may involve weeks or months of storage with minor leaching accumulating to a non-negligible level. And even then, my main thing would be "just drain it in between outings and you're golden". (also fwiw i collect pewter and have + regularly drink out sth like two dozen different tankards, no apparent heavy metal poisoning yet) Ambrose Burnside fucked around with this message at 00:58 on Feb 21, 2020 |
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Feb 21, 2020 00:52
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How would the amount of lead in pewter compare to the amount in lead crystalware?
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Feb 21, 2020 22:00
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The only lead-bearing pewter alloy in circulation likely to be formed into a food-contact vessel is trifling pewter, a historical alloy used for vessels and holloware b/c of its excellent forming and soldering characteristics; it had less than 5% lead content. You'd need to be drinking out of a very old hand-made antique to end up with trifling pewter, though. Honestly, pewter has been food safety-mindful for literal centuries, that 1974 date refers to when the EU established a standard for pewter across the entire trade zone, but- so far as I know- leaded alloys were already voluntarily excluded from stein/goblet-type goods by the western pewter-casting industry and/or guilds. if your pewter vessel was made in a Western factory of some sort and not your cousin ricky's cat-litter garage smelter or a Shenzhen pot-metal manufactorum, and it's less than 200 or so years old, i'd be comfortable assuming it's lead-free. Other servingware is gonna be britannia metal (92% tin, copper/antimony balance), fine pewter (molten tin stirred with a copper rod until the melt is saturated w ~1-2% max copper), or a modern lead-free alloy that uses bismuth as an alloying substitute for lead. Very cheap bulk casting 'pewters' can have up to 75% lead but those alloys absolutely are not used for tankards/vessels/flasks for a couple of good reasons beyond safety, their mechanical properties are very poor + they're heavy as poo poo In comparison, lead crystal has a composition including ~10-30% lead oxide by weight, and leaching is very much a known issue there, albeit only with prolonged storage- Items made of lead glass may leach lead into the food and beverages contained.[21][22] In a study performed at North Carolina State University,[23][verification needed] the amount of lead migration was measured for port wine stored in lead crystal decanters. After two days, lead levels were 89 µg/L (micrograms per liter). After four months, lead levels were between 2,000 and 5,000 µg/L. White wine doubled its lead content within an hour of storage and tripled it within four hours. Some brandy stored in lead crystal for over five years had lead levels around 20,000 µg/L. An ordinary diet contains about 70 µg of lead per day. Ambrose Burnside fucked around with this message at 23:23 on Feb 21, 2020 |
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Feb 21, 2020 23:11
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Hey so I'm wondering, why are almost all grinder wheels aluminum, or some other light material like plastic? Why not steel, it's cheap and wears better than aluminum for instance. Is it because they have more mass to spin up and so it robs the motor of power that could be used to drive the belt? I am assuming that is the reason, but I am wondering the logic holds up, because more mass = more momentum and that will help you when grinding, the wheels take more power to get up to speed but once there I don't think there would be much difference to keep it going and the increased mass of the wheels ought to help keep them rotating. I guess one thing that's easier to work around with light wheels though is vibration issues. Less rotating mass, less vibration. Just something I'm pondering since I've started drawing up 2d plans for this metric copy of Jeremy Schmidts 2x72 grinder. I got a lot of the material already, 10mm plate material, aluminum rounds for wheels (tho nothing suitable for the main drive wheel) and a 3hp motor. Still need the square bar which will be 40x40 mm. 
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Feb 22, 2020 13:00
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Ambrose Burnside posted:That's only regarding lay pewter, which you wouldn't make a tankard out of. Hell yeah, now I can enjoy me some ale, while still being able to see if I'm about the be attacked.
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Feb 22, 2020 16:01
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I need to put a ~100º bend in some 6mm zinc-plated steel threaded rod. Probs going to use a butane torch to heat it up and then just bend with pliers. Doesn't have to be super precise, and the threads at the bent part won't be used. Just forming a hook, basically. Is there anything I should be taking into account when doing so? Other than not setting myself on fire, obviously.
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Feb 22, 2020 19:53
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Use soft jaws in whatever vise you use to hold the piece so that you don't damage the threads. spin a couple of nuts on first so that if you do damage the threads, you can reform them a bit by screwing the nuts back off.
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Feb 22, 2020 19:59
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His Divine Shadow posted:Hey so I'm wondering, why are almost all grinder wheels aluminum, or some other light material like plastic? Why not steel, it's cheap and wears better than aluminum for instance. Is it because they have more mass to spin up and so it robs the motor of power that could be used to drive the belt? I am assuming that is the reason, but I am wondering the logic holds up, because more mass = more momentum and that will help you when grinding, the wheels take more power to get up to speed but once there I don't think there would be much difference to keep it going and the increased mass of the wheels ought to help keep them rotating. I think it's just ease of manufacturing. We purchase one type of very large belt grinder that has a bunch of aluminum drive wheels that go to poo poo in no time. After they do they are either replaced with steel or a heavily anodized aluminum. No real difference in performance that we can see. For something like the grinder you are building I doubt if using steel or aluminum or even cast would really change anything you could notice. Maybe because of rust too? Dunno. Some of our big grinders have aluminum bases, others cast iron, again no real difference.
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Feb 22, 2020 20:06
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Sagebrush posted:Use soft jaws in whatever vise you use to hold the piece so that you don't damage the threads. The only vice I have has softwood jaws, so should be alright there.
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Feb 22, 2020 20:09
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Jaded Burnout posted:I need to put a ~100º bend in some 6mm zinc-plated steel threaded rod. Probs going to use a butane torch to heat it up and then just bend with pliers. Doesn't have to be super precise, and the threads at the bent part won't be used. Just forming a hook, basically. Depending on the plating don't breathe the bright yellow smoke. If you're just using a mapp torch maybe you're ok, not sure at what temp it starts burning off. Edit for the non-ironworkers: fume fever comes from breathing in certain metals off the forge or when welding, the most notorious being galvanized. If you read forums people freak out that if you breathe in the littlest bit you will die which is untrue, but it definitely does suck and will take you out of action for a day if you get a strong dose. Double e: and just to be clear I'm not saying don't do it, just have good ventilation and don't stick your face in it you'll be fine. threelemmings fucked around with this message at 21:16 on Feb 22, 2020 |
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Feb 22, 2020 20:56
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I would bend that cold, tbh. If the rod is long you should have no problem getting enough leverage, you can slip some tubing over the unclamped tail end of the rod, acting as a handle of sorts, to help control where the bend happens + keep everything else machine-straight. As long as you're of baseline adult physical ability and your vise is beefy + well-bolted to a heavy workbench, 6mm soft galvy shouldnt be much of a problem. If you want a controlled radius/arc on the bend and not a relatively uncontrollable 'sharpish point', clamp the rod in the vise and have it pinch a stub of thick steel round bar between it and the jaw, near the edge of the vise. Bend the rod around the steel round, it'll take the profile and then spring back a little extra. But yeah, def avoid heating up galvanized steel where possible, and this sounds like one of those Possible tasks. You'll also usually get more consistent results bending cold if you're not a blacksmith, when steel gets soft it tends to move too much and in unwanted ways when you're inexperienced, and getting stuff machine-straight again can be hard without proper hotworking tools like an anvil. Ambrose Burnside fucked around with this message at 01:44 on Feb 23, 2020 |
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Feb 23, 2020 00:32
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His Divine Shadow posted:Hey so I'm wondering, why are almost all grinder wheels aluminum, or some other light material like plastic? Why not steel, it's cheap and wears better than aluminum for instance. Is it because they have more mass to spin up and so it robs the motor of power that could be used to drive the belt? I am assuming that is the reason, but I am wondering the logic holds up, because more mass = more momentum and that will help you when grinding, the wheels take more power to get up to speed but once there I don't think there would be much difference to keep it going and the increased mass of the wheels ought to help keep them rotating. I'm guessing but some factors I can think of: Steel, being more mass, would put more wear on bearings, which would therefore need to be more robust To deal with vibration of more mass, steel wheels would probably have to be balanced at the factory, which is costly With more rotational mass, during start and stop operations there's a lot more momentum as you said. But that means slower to start up and slower to stop. The latter could even be a safety issue: hit the emergency stop button and it keeps going for longer? All that said, the pulley wheels on car engines that I've seen are usually either stamped steel or some kind of plastic or resin, and sometimes aluminum, it seems like it's all over the place but I bet you could make lightweight stamped-steel pulley wheels out of steel that would perform very similarly to aluminum. So ultimately I dunno it feels like an odd thing to only ever see aluminum or plastic, you're right.
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Feb 23, 2020 01:10
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Yeah that's a good point ref. experience. Also when making mirror frames or very large things with long gentle curves we do it all cold with forks for that reason, consistent slow curves are easier to do cold so you don't have to deal with flat spots or kinks. Guess it depends on your use case here. Also I didn't do the math in my first post. You can definitely make that turn cold by hand as long as it's longer than a foot or so or if you make a monkey tool like Ambrose suggests. Hell you could just find a metal fence or rail and use that as a bending fork, 1/4" is pretty whippy if it has any length at all. threelemmings fucked around with this message at 01:21 on Feb 23, 2020 |
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Feb 23, 2020 01:17
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IRT the grinder wheel question: a flywheel component does store energy, which would provide some benefit on a grinder, but you have to weigh that against all the disadvantages + costs a bunch of flywheel mass comes with in design terms, a couple off the top of my head: - needs a stronger motor to compensate for the added system mass - motor, bearings, shafts and the tool base/frame must all be heavier-duty to account for the added operational stresses (vibration, torque on motor start/stop, etc) a heavy flywheel adds, or otherwise the tool is apt to wear out or fail much quicker - a bunch of safety considerations that didn't exist previously must now be considered, if a shaft/key/bearing fails at speed and the flywheel gets loose, it turns all its stored rotational energy into linear kinetic impulse and takes off, probably putting a hole in the wall. when i was younger i was almost seriously injured by a heavy stone grinding wheel that came loose due to being improperly assembled by the last person who'd hosed with it (and my fault for not double-checking); it left a friction burn strip from chin to cheekbone, just grazed me on its trajectory into the shop's dusty back 40, but if it'd been an inch lower it would have hit and broken bone instead. compare all those to the only real benefit a flywheel offers, a couple moments' extra working time at the grinder's unloaded RPM as compared to its reduced RPM under load. It's still gonna slow down, it'll just take slightly longer. And then take longer to spin back up, of course. Is there any benefit at all there, once you factor in the added spin-up time? Doubtful, imo. And given the extra design considerations, it just seems like a bad idea all around. Reduced wear isn't a serious consideration, I don't think; pulley wheels don't need the strength of steel for the application of a belt grinder, don't experience significant wear on their working faces, and anywhere that IS high-wear will have replaceable bearings to account for that. the appropriate solution to a bench grinder that bogs down in use is to size the motor up, not add extra load to an already-overtaxed motor Ambrose Burnside fucked around with this message at 02:02 on Feb 23, 2020 |
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Feb 23, 2020 01:59
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RE: grinding wheels. My bet is that cost also plays a significant factor. You presumably want to machine the OD and ID pretty drat concentric. Machining it out of aluminum is going to be a lot faster and cheaper than steel. I'd also wonder if corrosion resistance is a concern, since unlike the frame you can't really paint the wheels. That just doubles the cost factor, since now you're comparing to machining stainless (very expensive.) Also, I'm a little doubtful that steel would add too much to the spin-up/down time, since they're pretty small in diameter, but I haven't done the math. If it is significant, then that's probably a disadvantage for steel. You're probably going to be changing belts a lot more than a big belt sander, so a slight difference in acc/dec could add up.
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Feb 23, 2020 02:27
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Karia posted:Also, I'm a little doubtful that steel would add too much to the spin-up/down time, since they're pretty small in diameter, but I haven't done the math. If it is significant, then that's probably a disadvantage for steel. You're probably going to be changing belts a lot more than a big belt sander, so a slight difference in acc/dec could add up. i'm not 100% on this 'cause it's been quite a few years since a dynamics course, so i might eat poo poo on this, but: i'm p sure the system would categorically break even before considering inefficiency losses. the same conditions apply to both speeding up and slowing down, in terms of flywheel size/mass, available motor torque, baseline frictional losses, and the same delta-V (difference in velocity between state 1 (max unloaded grinder RPM) and state 2 (acceptable reduced RPM while under load). the only known variable that changes is the total frictional loss, which will be higher under load (the work performed just adds to the overall system friction, as far as we're concerned, so we don't need a new variable). the variable we solve for is time. the actual numbers don't matter, though, we care about the relationship between t1 (time from state 1 -> state 2) and t2 (time from 2 <- 1 ). it will be something like a fixed ratio, with the unloaded spin-up time being quicker. 1:2 spin-up to slow-down, 1: 1.5, who knows, something like that. the only way to change this without altering the equipment is to do less work, which is counter-productive. so if you go and change another one of the variables for both equations, in this case the density and therefore total mass of the flywheel, you change both numbers, and the change is fixed proportionally. if the wheel takes twice as long to slow down, it will also take twice as long to spin back up. no net benefit. you would get the same result if you made the flywheel bigger in any dimension but kept the density the same, or changed the disc to a flywheel geometry with a different inertial constant (a pulley will have a better constant than a simple cylinder because it puts more mass at the edge, for example). but as long as it's the same wheel that's doing both the slowing down adn the speeding up, and the same motor doing the turning, the fundamental relationship between slowing and accelerating won't change in a useful way. Ambrose Burnside fucked around with this message at 05:09 on Feb 23, 2020 |
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Feb 23, 2020 03:29
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Ambrose Burnside posted:i'm not 100% on this 'cause it's been quite a few years since a dynamics course, so i might eat poo poo on this, but: Two points: 1. First, your memory from dynamics is absolutely correct: a heavier flywheel will take longer both to spin up and to spin down. Moment of inertia doesn't care whether your Δω (capital delta is change, lowercase omega is rotational velocity) is clockwise or counterclockwise. So your general point is right! I'd also add air friction to that list, I haven't done the math to check but it might actually be significant at 2000+ feet/minute. But I'd also bet that the motor is used to speed it up, but probably isn't used to brake. So the actual time difference will be heavily asymmetric. I don't have a belt grinder, but checking some videos shows that's correct. Very fast startup, but a couple of seconds of wind-down. 2. But that's not what I'm trying to argue. If, say, you're using your belt grinder to sharpen knives, you're going to be swapping between belts pretty often as you go through the grits then the polishing belts. That means that you want to waste as little time changing belts as possible. Both acceleration and deceleration time are wasted since you can't be grinding and you can't be changing the belt. So if the aluminum is significantly faster for starting/stopping, then that saves time waiting for the system to stop when you want to change a belt and when you're waiting for it to spin back up after you've changed the belt. There's only one way to settle this: Shadow, please make both steel and aluminum wheels for your belt grinder, and report the following:
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Feb 23, 2020 04:37
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Karia posted:
Whoops, I missed that. And yeah, complete agreement if we're talking knife-grinding, I didn't think of that aspect because Ive used my own belt grinder almost exclusively for refining the shape of double-digit-quantity batches of little titanium utensils. Only one belt change per 45 minutes or so, and I was only using two belt grits for that work because I wasn't putting a fine edge on anything. in any case we're in agreement that more wheel mass =/= better than (also yeah i forgot that the motor doesn't brake on load being applied, that's still one of those fixed-variable things but it makes my made-up ratios particularly made-up and wrong) Ambrose Burnside fucked around with this message at 05:11 on Feb 23, 2020 |
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Feb 23, 2020 05:07
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So what I'm making is effectively a J-bolt to replace one that broke in my car's battery holder. The hook end doesn't need to be precise at all, just hook-like, and the main body of the bar doesn't need to remain machined-straight so long as a decent section at the top is straight and threaded enough to put a nut on. I'll give it a try cold first, through I don't have a metalworking vice, just a woodworking one, but I'm sure I can jury rig something.
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Feb 23, 2020 07:09
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| # ? May 27, 2024 21:07 |
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Re: the wheels so okay it's best to keep them as light as possible. I don't think rust is really an issue in my shop. But I realized too that a steel wheel can be turned to a lighter profile than an aluminum wheel could so the difference might not be that great depending on design. I'm mostly thinking about this since I don't have suitable aluminum for the main drive wheel and I want it to be big, like 6" in order to get as high an SFPM as possible from my motor which is a 1420rpm 3 phase motor. I wasn't planning on using a VFD with it. And yeah this machine will be heavy, 40x40mm solid square bar in the center for holding the table and platen attachments, the majority of the parts are made from 10 mm steel. Everything is just a little thicker than Jeremys design since I decided to round up instead of down when converting from inch to metric.
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Feb 23, 2020 08:59
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