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420chan is Getting Overhauled - Changelog/Bug Report/Request Thread (Updated April 10)

/a/ - Anime & Manga Discussion Now Available
Flying Ignore Report View Thread Reply
2017-01 - Fri, 06 Jan 2017 19:50:34 EST ID:cbS5u/gp No.7037
File: 1483750234304.jpg -(360613B / 352.16KB, 2000x1333) Thumbnail displayed, click image for full size. 360613
Anyone here likes jets? Helicopters?
Samuel Hemmercocke - Wed, 01 Mar 2017 15:06:37 EST ID:El6x3uF1 No.7111 Ignore Report Reply
they should get rid of the cockpit and dumb down the f16 since it is going to be disposable

Newclear Womb Ignore Report View Thread Reply
Skit Pwn - Mon, 30 Jan 2017 20:27:23 EST ID:xYshtut8 No.7041
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Does anyone have a copy of Multiphase Flow Dynamics 2: Mechanical Interactions by Nikolay Kolev? If not, where would be a good place to download it? I can't find any torrents.

If not, than hey here's a guy who says things...
Cyril Pittbanks - Fri, 03 Feb 2017 13:22:40 EST ID:LMSWX1C6 No.7042 Ignore Report Reply
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Simon Crumbledetch - Wed, 22 Feb 2017 16:50:34 EST ID:E/liXdBm No.7044 Ignore Report Reply
1487800234237.jpg -(205235B / 200.42KB, 1083x1351) Thumbnail displayed, click image for full size.

SUPERLOOOOOOP Ignore Report View Thread Reply
Nigger Pivingwidge - Tue, 13 Aug 2013 16:36:10 EST ID:NBJ0w/MW No.5836
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Musk finally put out some information on his hyperloop public transportation idea. It looks amazing, but I'm not really /tesla/ enough to know if it's really viable. Anyone here want to take a look? The attached link is the full text of the proposal.

7 posts and 1 images omitted. Click View Thread to read.
2017-01 - Fri, 06 Jan 2017 20:53:35 EST ID:cbS5u/gp No.7038 Ignore Report Reply
What's wrong with trains or light rail?
Henry Drallykog - Thu, 19 Jan 2017 10:22:22 EST ID:JLlZ+fjU No.7040 Ignore Report Reply
The Hyperloop: BUSTED!
Simon Crumbledetch - Wed, 22 Feb 2017 16:51:55 EST ID:E/liXdBm No.7045 Ignore Report Reply
1487800315237.jpg -(40324B / 39.38KB, 640x422) Thumbnail displayed, click image for full size.

copying old parts Ignore Report View Thread Reply
Wesley Clunnermodging - Thu, 26 May 2016 00:35:47 EST ID://p8h2A8 No.6963
File: 1464237347308.jpg -(23612B / 23.06KB, 400x296) Thumbnail displayed, click image for full size. 23612
hey /tesla/

I'm an eletrical engineer that likes to work on old cars. While bidding on a nos battery bracket for my current project, it dawns on me, wouldn't this shit be cheaper if the people that had the parts, scanned them and got new stuff made, instead of us all bidding the few remaining parts up?

Does anyone know how I can get into making copies of the parts I have so others can use them? 3d scanning?

Some of these parts are pretty simple. Just various bent bits of metal with bolt holes and you assemble them into brackets for mounting this and that. I would think I could draw that up in autocad or solidworks. But finishing it is a bit beyond me. I have like 2 years of autocad but I was never trained on how to select metals or what I've always called "fit"

Like, how do I even draw the bold holes and the botls just right that when they build it for me, all the shit goes together just right and isn't too tight?

Can anyone help me with this?
3 posts omitted. Click View Thread to read.
Jack Honeyspear - Thu, 09 Jun 2016 11:45:51 EST ID:LMSWX1C6 No.6971 Ignore Report Reply
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Go watch Dan Gelbart's series on prototyping and get a feel of how to become independent and less reliant on premade solutions for parts that you can belt out in minutes with some elbow grease. Some shears/tin snips/wire cutter/cut off wheel to cut the rough shape out. A drill press to drill and hand shape the rest(or hand drill and rotary hand tool). Brake bend with a few pieces of scrap board and c clamps, heat the radius with blow torch if it's really thick and use some harbor freight welding gloves to handle. If it can't be simply bolted and locktighted together, or glued, than consider making a spot welder from some microwave parts at some point.
As far as material. 10-14 ga. is probably fine for most project brackets. If things are under load then the housing, struts, bearings, and suspension systems take care of that, not mounting brackets.
Old appliances like computer panels and such are free source of thick sheet. Old tins from holiday containers are another source of thinner material.

Obviously he has hundreds of thousands of dollars of machinery at his disposal, but with the suggestions I made above you have alternatives for pennies on the dollar.


Some other things if you like having a layed out plan that helps are: dykem, paint pen, calipers, scribe, scale or carpenter square, radius gauges, and a compass.

CAD experience is kind of pointless if you don't have real world field experience. Don't turn into one of those guys that have twenty different true position tables and +/- .0001" on every dimension for a part that only needs saw and drill hole tolerances.
Get your hands dirty and make yourself a valuable go to designer.
Ian Denkinkatch - Fri, 05 Aug 2016 06:56:19 EST ID:/GtFGFci No.6979 Ignore Report Reply

Some top quality advice from this guy. I agree with this so much it makes me wonder if I got drunk, posted this and then forgot about it.
2017-01 - Fri, 06 Jan 2017 19:40:43 EST ID:cbS5u/gp No.7036 Ignore Report Reply
Borrow/rent some usage time from the local uni or science facility

Anyone built a free energy device ? Ignore Report View Thread Reply
Rebecca Packlepure - Wed, 23 Jul 2014 12:30:50 EST ID:fTAGL71n No.6417
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I did and it sort of works.
15 posts and 4 images omitted. Click View Thread to read.
Betsy Turveyfield - Sun, 11 Dec 2016 20:47:08 EST ID:GWmaubj1 No.7032 Ignore Report Reply

I've never seen these before but by the looks of it you can increase the power generated by using a bigger antenna. As something to translate reported voltages in to something relatable, the amount of energy stored in a capacitor is determined by the size of the capacitor and the voltage.

energy in joules = capacitance in farads * voltage^2 / 2
energy in joules = power in watts * time in seconds

So a 1000uF cap charged to 100 V has 5 joules of energy stored. If you could convert it to whatever kind of power you need with 100% efficiency it could run a 1 watt load for 5 seconds.
Lillian Womblehedging - Mon, 19 Dec 2016 03:08:43 EST ID:WiAbb/Pm No.7033 Ignore Report Reply
Maybe we can get some slav to buy a bunch of car batteries and raid the local Radioshacks and hook this shit up to the Duga's over in Ukraine.
Nigel Nirrybure - Tue, 03 Jan 2017 20:37:26 EST ID:KdBRMlw9 No.7035 Ignore Report Reply
theoretically would the circuit, if there is more length on the connected diodes , produce more voltage?

Cheap/free Mechanical Engineering 101 resources? Ignore Report View Thread Reply
Cedric Passlefoot - Sat, 24 Oct 2015 21:36:21 EST ID:gQzPZ5om No.6824
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Basically what the title says. I have an intense interest in Mechanical Engineering. I want to pursue a career as an Auto Mechanic and will be attempting to get into a decent college that has both automotive and mechanical engineering programs. But while I'm waiting on that I figured it best to educate myself outside of school I suppose. So I'm looking for a place to get really cheap introductory textbooks on the matter, maybe free or cheap online PDF's as well. Does anybody have any suggestions?

I know that taking courses in Mechanical Engineering isn't exactly a requirement to be an automotive mechanic but I want to create, design, and fabricate as well as do repairs. I seem to have at least a little bit of a latent talent when it comes to machines as I managed to partially disassemble an old motorcycle engine to replace a bad valve and gasket as well as adjust the timing chain after only watching a short instructional video. Sure I had to take apart and put the engine back together a few more times before it fired up but, hey, I got it. And this was with no prior experience with that sort of thing.

I also seem to really enjoy the work, I found it intensely fun. Anyway, I digressed quite a bit there. I was looking for books/resources on things like learning how to do C.A.D. and/or how to draw up design plans on a drafting table (do people still do that?). The math needed behind the subject (math comes naturally to me, especially things like geometry and calculating ratios which I think has at least a little to do with all of this?) As well as general education on the matter. I can't really give any specific examples but, I figured I'd start broad and work my way into more of a specialized area. I want to design everything from internal combustion engines (new and exciting configurations!) to glider planes. In essence I suppose I want to focus on vehicles and transport in general.

Anyway TL;DR - Cheap and/or free mechanical engineering resources, anyone? please?
4 posts and 1 images omitted. Click View Thread to read.
Graham Bliddlestadge - Sat, 28 May 2016 23:45:03 EST ID:Zl+5ngCO No.6964 Ignore Report Reply
>implying mechanics in America are highly trained and qualified
Most of them are white trash. Go be a helper at a shop and they'll teach you what you need to know. Most places care about experience unless it's in the plants or government work.
Sophie Clayspear - Sun, 21 Aug 2016 04:46:03 EST ID:7YnJeYuF No.6988 Ignore Report Reply
Machinist's Handbook. Anything you could ever need will be in there. Mechanical Engineers are all pencil pushing know-it-alls cunts. I hate Mechanical Engineers. I left the field behind because of those shallow pedantic fucks. Engineer school teaches you a bunch of shit when a Machinist's Handbook would cover everything you'd use in the real world.

Pirate some ansys software, solidworks, Mastercam and blender. Learn them in that order, backwards. Ansys will be great, way way way down the road for you. Blender is good right now and it has input values so you can test designs to make sure you won't run into costly errors. It is going to take a ton of dedication but you can do it if you want it enough of course.

Machinist's math textbooks are aight. The rest are a waste of time or far too overly complicated to make engineer school more of a pain.

>Seriously though, Machinist's Handbook. Outside of design and that sort of shit, anything you need fabwise will be in there. And millions more.
Hugh Dronningman - Mon, 28 Nov 2016 07:38:48 EST ID:IjPN+/1M No.7019 Ignore Report Reply
MIT has literally all the resources(lecture recordings, textbooks, software ect) necessary to get a complete undergraduate education in mechanical engineering available to download for free


tool Ignore Report View Thread Reply
Betsy Tootlock - Fri, 25 Nov 2016 07:29:05 EST ID:LcB05FSQ No.7018
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What's the tool called he uses to remove the bolts at 1:10?

Rebecca Ginnerstare - Wed, 07 Dec 2016 22:01:19 EST ID:dLNwpFpO No.7030 Ignore Report Reply
I would call that a ratchet driver.

Tesla Stuffs Ignore Report View Thread Reply
Reuben Bubberbotch - Thu, 14 Feb 2013 21:10:41 EST ID:7rz8obbR No.5412
File: 1360894241017.jpg -(10341B / 10.10KB, 220x295) Thumbnail displayed, click image for full size. 10341
First year computer engineering student here, with failed subjects.

Well, what drag me into the waters of engineering is all about Tesla and his stuffs. Skeptical, as always, why his stuffs and other stuffs of aspiring people when it comes to Free Energy isn't wholly, or eventually, seriously taken by people.

It's quite mind-boggling for me, I don't even get how much 'value' it is for one to pursue this stuff. I mean, other people already did, no one gave a fuck and here am I just sitting here trying to conclude on a pessimistic matter on what could fucking happen on the next fucking years, or even decades.

I was literally keeping a library of all of stuffs related to free energy, like almost 40gb of it stored on my HDD. Just.. just irritating on why am I thinking this way.
11 posts and 3 images omitted. Click View Thread to read.
Oh Niner - Thu, 15 Sep 2016 07:42:54 EST ID:m4ZDEG1O No.6989 Ignore Report Reply
Tesla makes nice EV cars. Wait.. it's Elon Musk?
Eugene Sondlefoot - Fri, 11 Nov 2016 07:12:16 EST ID:v644jtd6 No.7014 Ignore Report Reply
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Lydia Curringnatch - Sun, 13 Nov 2016 09:00:06 EST ID:4M/IZJux No.7015 Ignore Report Reply
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FFFF Ignore Report View Thread Reply
Emma Daffingdock - Sun, 06 Nov 2016 00:32:25 EST ID:PXawepa+ No.7013
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Damn, no wonder military technology is still in the 70's.

Electrical engineering Ignore Report View Thread Reply
Nell Hecklebury - Mon, 17 Oct 2016 08:20:05 EST ID:JoiHGtE7 No.7008
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Hi i am at the 2nd year of computer engineering however i must study a bit of electrical engineering but from my book i don't understand a single word
anyone can suggest me a book or a site where everything is explained well?
Alice Duckstone - Tue, 18 Oct 2016 13:03:13 EST ID:LMSWX1C6 No.7009 Ignore Report Reply
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Like what sort of stuff don't you understand, what book do you have, and what's the outline of the course?
I'm guessing you're also ESL, which is going to be detrimental if you lack communication skills.

Chinesium Ignore Report View Thread Reply
Basil Suddlewell - Thu, 22 Sep 2016 04:22:38 EST ID:+tz+iBph No.6991
File: 1474532558416.jpg -(85221B / 83.22KB, 720x960) Thumbnail displayed, click image for full size. 85221
So, what is this magical, and presumably very cheap substance that Chinese $2 shop crap is made out of? Is it metal or plastic, or some combination of the two?
Has anyone tried analysing this crud, or how they make things out of it? It seems too brittle to be machined, maybe it's moulded and sets like that play-dough stuff you bake in an oven. But put it under mechanical stress and it deforms, tears and crumbles like cake. Sometimes it has sparkles!
3 posts omitted. Click View Thread to read.
Samuel Bubbertadge - Tue, 27 Sep 2016 22:50:53 EST ID:LMSWX1C6 No.7002 Ignore Report Reply
They're just made from pop steel you'd use for bottom barrel part fabrication. They're not even case hardened for the full length, as far as I'm aware.

Yeah, don't fuck around with garbage cutting tools. They'll bite you more than the material. If the manufacture isn't willing to provide you a name of the material it's tool is made from, I'd be hesitant. You know something telling you it's a M42, M2, C2, C12, etc.
Isabella Dregglestone - Wed, 28 Sep 2016 05:55:39 EST ID:2R1lBWwz No.7003 Ignore Report Reply
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I love the drill-bit where the threads have straightened out like spaghetti.
You Google image search for Chinesium and it's like a mechanical hall of shame.
George Nuckleworth - Wed, 05 Oct 2016 23:23:52 EST ID:ZMpXliD1 No.7007 Ignore Report Reply
industrial supply places are the best for stuff like this. The bits I get at my shop are pretty solid.

WHAT HAS SCIENCE DONE Ignore Report View Thread Reply
Basil Suddlewell - Thu, 22 Sep 2016 05:02:20 EST ID:+tz+iBph No.6992
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Edward Brobblewill - Fri, 23 Sep 2016 02:05:48 EST ID:gO+6q97s No.6994 Ignore Report Reply
test post please ignore

Pulley ratio calculation Ignore Report View Thread Reply
Cornelius Blackcocke - Thu, 04 Aug 2016 13:53:21 EST ID:0ltnlAdQ No.6978
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Hi, I hope this is the right board for this. After a few hours of looking online..I just don't have the math skills to sort this out.

I have this electric motor that spins at 1725 rpm. I need to reduce that to 25-30 rpm. I have an old 74 1/4" bicycle wheel that I hope to be able to use but need to know the size of pulley to attach to the motor, or even if it is possible with what I have. I want to use this motor because it is designed for extended use and has a sufficient amount of torque for my project.
5 posts omitted. Click View Thread to read.
Jack Baffingshit - Fri, 12 Aug 2016 23:36:36 EST ID:LMSWX1C6 No.6985 Ignore Report Reply

Oh yeah, you really don't have to clean up the faces of the pulley either, an uneven cast surface is fine. As long as the surface the belt sits on isn't severely out of round(not enough even, constant pressure on the cut, or not not cutting far enough past the rough cast surface).
If you decide to clean the faces up, and want to do it with some speed. I know a lot of people often have something like an angle grinder laying around, so if you put the drill with the pulley to a low RPM, you can hit it with light passes of the angle grinder to speed up cleaning the faces up. If it's glued in, don't go to hard, or you could heat it up and melt it out.

Alternatively to a glue on mandrel is to take a rod, drill and tap the face. This goes in the chuck and the part is bolted to it, with a little touch of locktight. Just make sure the part spins in a direction that pushes the bolt tighter, rather than looser as you put pressure on it.
Sophie Clayspear - Sun, 21 Aug 2016 03:51:28 EST ID:7YnJeYuF No.6986 Ignore Report Reply
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Not sure why you are building a directly driven rock tumbler. Most are a 1:1 drive to one support rod that the drum rotates on. Usually with something rubber to prevent slippage. Pic related.

By Direct Drive I assume your design is a gang of linked 5 gallon buckets with one attached to a bicycle wheel as a driven gear?

This may be necessary given you are talking 6 feet long and 5 gallon buckets. Not sure what loads you will have. If you are turning 5-6 5 Gallon buckets with rocks, internal blades/mixer shelves and water, you could be moving a good bit of weight.

This is what I would do if you are attaching the wheel to one of the drums with all the other drums connected to the driven one. I assume by 74.25 you are talking about the circumference. So the diameter is 23.5 inches? This is going to make the design pretty... shitty. To gear it right. You'd need a .5" pulley. You'd also be going through belts fast with such a sharp angle unless you put the motor very close to make the belt's tangency less sharp. If you want to use the wheel and the motor you'd do best with a VFD device but those are about 110 dollars for a tiny one.

The math behind this is:

>5/8" Drive
>23.5" Driven
>1725 input.
>15" between centers and a ~3" gap between pulleys. A little over 3"
>Belt length should be roughly 75.5 inches. Of course you should be able to tension it by moving the motor. Or an idle I guess.
>55 RPMs at the driven. Still kinda fast. .5 inch would be optimal.
Sophie Clayspear - Sun, 21 Aug 2016 04:38:59 EST ID:7YnJeYuF No.6987 Ignore Report Reply
1471768739822.png -(19879B / 19.41KB, 1024x768) Thumbnail displayed, click image for full size.
This is the optimal way of doing it unless you expect to be turning 60-100 lbs or more.

>Green is Drum. It rides on the two 6 foot bars. Wrap these in electrical Tape or something rubber. This won't work if these are tiny as shit. If they are over .5" in diameter, it should work.
>Black rectangle is the mounting for the bearings and shit.
>Red crossed circles are your pulleys.
>Yellow Cross circle is your motor pulley.
>Light blue around the circles is the belt.
>The blue lines in the black long rectangles is your 6ft pipe.
>Motor is self explanatory. Mount it in a way you can tension the belt. Threaded rod could work. You could put nuts on the threaded rod and tighten the nuts til the belt is tight. Then run a second nut under it and tighten them against each other so it doesn't vibrate down.

This is where things get complicated. This design is far superior, cheaper, durable and easier. But the math is more involved.

Firstly, I need to know the diameter or the circumference of the outside diameter of the pipe the drum will rest on. Then I will need to know the diameter or the circumference of the drums. Nothing too precise but I'll show you so you can work it yourself.
Comment too long. Click here to view the full text.

Ground Needed\Stray Voltage? Ignore Report View Thread Reply
James Pillyhood - Wed, 13 Jul 2016 23:38:51 EST ID:LMSWX1C6 No.6975
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So I got a new attic fan and lighting wired up and there is no ground available on the circuit coming from the breaker. Option one I'm seeing is to run a wire out the wall, tucked under the siding all the way to the ground rod, bloating this "simple" project even more; or just say fuck it and not run a true ground to it, even though I spent the time tying all the ground wires together; third option bite the bullet and buy a GFCI breaker.

Problem 2, when I put the voltmeter to the case of the fan, after flipping the breaker on, I get 1 volt on the case. Should I be concerned with this, is this excessive stray current?
Cedric Cunkinferk - Thu, 14 Jul 2016 21:15:26 EST ID:3ODb0gls No.6976 Ignore Report Reply
I would probably just install a fuse on the power wire to the fan.
Lillian Brookbanks - Thu, 14 Jul 2016 23:37:17 EST ID:LMSWX1C6 No.6977 Ignore Report Reply
Suppose that could work. Haven't seen a fuse outside of a car circuit in a long time. Don't think any stores even carry holders around here. Have to order one.

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