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Tin Can Predicament by Cyril Honeyridge - Sun, 20 Apr 2014 13:51:37 EST ID:5gD9lQi4 No.6264 Ignore Report Reply Quick Reply
File: 1398016297652.png -(45544B / 44.48KB, 1103x1305) Thumbnail displayed, click image for full size. 45544
Heyo, /tesla/

I got a quick problem that needs solving.

I have a tin can I need overlapped onto the end of the other, such that 2 holes line up. I did my best to show this in sketchup (see picture).
I'm thinking I should cut about an inch at 8 points equidistant from each other around the rim of the upper can and fold the tabs alternating in and out, but I need a second opinion from some legit engineers.

Lemme know what you think.
5 posts omitted. Click Reply to view.
Fuck Crubbertadge - Tue, 22 Apr 2014 09:57:40 EST ID:RVngPBEo No.6270 Ignore Report Quick Reply
For a few minutes, until the aluminum starts to overheat, expand and cause catastrophic failure.

The trick is to get the shaft turning at a high enough speed so that the air flow is maximized before adding any fuel to burn. That way, the exhaust turbines won't seize up and melt everything.
Jack Turveyspear - Tue, 22 Apr 2014 10:09:36 EST ID:LNG8f7Rs No.6271 Ignore Report Quick Reply
I imagined this is in soda cans. I just thought the suction from the intake would be enough to warp it along with the heat and force coming from the back
Priscilla Grandlock - Wed, 23 Apr 2014 14:48:00 EST ID:RVngPBEo No.6275 Ignore Report Quick Reply
1398278880724.png -(386384B / 377.33KB, 481x420) Thumbnail displayed, click image for full size.
Molly Bubbernedge - Wed, 23 Apr 2014 19:04:54 EST ID:LNG8f7Rs No.6276 Ignore Report Quick Reply
1398294294169.gif -(593564B / 579.65KB, 480x360) Thumbnail displayed, click image for full size.
I told you I was a dip shit
Eugene Nengerdin - Sat, 26 Apr 2014 22:02:57 EST ID:RVngPBEo No.6284 Ignore Report Quick Reply
OK, scratch that.

I need one can to fit ENTIRELY over the other. None of that alternating in/out tab nonsense. Short of cutting down the entire length of the outer can to fit around the inner can, what can I do to make this happen?

3d Printing by Nicholas Shittingfield - Tue, 04 Mar 2014 18:06:15 EST ID:kWAgYbio No.6184 Ignore Report Reply Quick Reply
File: 1393974375035.jpg -(2230224B / 2.13MB, 3845x2889) Thumbnail displayed, click image for full size. 2230224
Hey /TESLA/, I recently came across an invention that involves reinventing the basic metal screw.
I've been looking into 3d printers so I don't have to take my idea to China. Though I am filing a patent soon and I may be forced to outsource it.
I'm just looking for experts on the subject, maybe direct me to the cheapest, most practical personal-use 3d printer that only produces small stuff.
I'm searching, but so far all I'm finding are these massive rigs for making guns and engines lol
5 posts omitted. Click Reply to view.
Archie Clockleshit - Thu, 13 Mar 2014 19:26:06 EST ID:bgxxcMnM No.6214 Ignore Report Quick Reply
1394753166066.jpg -(579688B / 566.10KB, 1280x1280) Thumbnail displayed, click image for full size.
Well this will depend on the type of material you intend to use, as each material has a benefit. In my experience, solid models of parts are best presented by FDM (Fused deposition modeling). It melts a small filament of plasting as it prints in 3D, thus creating a model that is basically solid plastic. In this case, Fortus makes fantastic 3D printers for FDM processes.

Another great part modeling material is with Objet printers. They utilize a light cure resin that is somewhat brittle, but comes in many specific variations. The limitation with this is that the model material is encased in a gel of support material that needs to be thoroughly (see painstakingly) removed.

Regardless of choice, it will run you a couple grand for a good machine with which to to solid model prototyping.

Pic is of powder modeling. It uses a sugar based liquid through an inkjet head to solidify a baking soda like powder. It suck don't use it ever, weak parts and a huge mess.
Fanny Pindertut - Sun, 16 Mar 2014 02:28:51 EST ID:kWAgYbio No.6220 Ignore Report Quick Reply
Ya that looks like a bunch of preserved sandcastles lol. I believe the technique for my first permanent prototype will be of stainless steel by means of FDM.
Charlotte Sunkinpack - Mon, 24 Mar 2014 04:48:18 EST ID:nSYRePSf No.6228 Ignore Report Quick Reply
>reinventing the basic metal screw.

Self Sealing Stembolts?
dave !N5MvbCntdE - Sat, 19 Apr 2014 14:50:17 EST ID:WCjzl674 No.6263 Ignore Report Quick Reply
I'm thinking of getting a reprap kit to make my own plastic parts, and maybe consumer goods. they're getting cheaper than photo printers which is cool.
Anybody have advice for a 3D printing n00b?
Oliver Tillingworth - Fri, 25 Apr 2014 04:13:12 EST ID:kWAgYbio No.6282 Ignore Report Quick Reply
Nope, it has more has to do with solving a long dismissed problem on guitars.

Stairclimber wheels by Samuel Hunderwidge - Sun, 19 May 2013 11:31:09 EST ID:t6Yu9g/A No.5663 Ignore Report Reply Quick Reply
File: 1368977469052.jpg -(110736B / 108.14KB, 1000x598) Thumbnail displayed, click image for full size. 110736
So how come these never caught on?
2 posts omitted. Click Reply to view.
Isabella Pickshit - Fri, 24 May 2013 08:18:08 EST ID:61FQy/W4 No.5692 Ignore Report Quick Reply
why dont i just get a bigger wheer that will climb over it either way?
Charles Benderchit - Sat, 25 May 2013 09:20:35 EST ID:Hp4T43CN No.5694 Ignore Report Quick Reply
The triwheel has a few good tricks unique to itself.
It absobs an impact by rotating, even though the Landmaster had no suspension the ride was smooth even at high speed over rough terrain, check the videos, they were really moving, but every time they hit a rock or hole the triplet just swings over.
It can climb by locking the wheels and running power to the triple wheel brace. Like that it moves like it has legs and will clear obstacles that would stop even a wheel that size.
If a tyre blows, you can just roll it over and lock the frame.
You can run the wheels AND triframe, and use it as a paddlewheel.
John Brookspear - Thu, 03 Apr 2014 16:03:14 EST ID:MOd48Kn3 No.6239 Ignore Report Quick Reply
It looks like it would feel rough to have the triwheel rotate while riding in it.
Barnaby Blenkinchitch - Sat, 05 Apr 2014 12:44:10 EST ID:8GdYYP4I No.6240 Ignore Report Quick Reply
fewer moving parts?
Nathaniel Buncocke - Fri, 18 Apr 2014 17:50:39 EST ID:xZgv+GY1 No.6258 Ignore Report Quick Reply
ur mom feels rough when im riding her

dumb and bad device idea by Oliver Fallermork - Mon, 14 Apr 2014 10:31:01 EST ID:7zEswIka No.6251 Ignore Report Reply Quick Reply
File: 1397485861729.jpg -(61737B / 60.29KB, 700x465) Thumbnail displayed, click image for full size. 61737
DRM to the ears. earbuds that take an encrypted digital signal to a digital circuit in each earbud, which then decrypts it, and then energizes a driver - with almost no wire - attached directly to the center of the IC. securely give audio to humans only.

:x i think it would be pretty cool though. perhaps if music generated more revenue, the music released would be much better. none of this good faith enough people are buying it bullshit
Oliver Fallermork - Mon, 14 Apr 2014 10:32:22 EST ID:7zEswIka No.6252 Ignore Report Quick Reply
plus you could radio tracks before the album comes out

Pilot Plant Real Book by Edward Disslefuck - Wed, 09 Apr 2014 00:53:09 EST ID:UC+qXdSi No.6241 Ignore Report Reply Quick Reply
File: 1397019189094.png -(234926B / 229.42KB, 1680x1050) Thumbnail displayed, click image for full size. 234926
Does anybody have a pdf of it?

Mimic a Remote's IR Code by Faggy Febberput - Thu, 27 Mar 2014 01:47:11 EST ID:FABnkK5n No.6232 Ignore Report Reply Quick Reply
File: 1395899231735.jpg -(144845B / 141.45KB, 720x540) Thumbnail displayed, click image for full size. 144845
My goal is to make a little circuit with an IR LED that can function as the original remote. So I need to somehow "learn" that original code from the original remote and program that into the circuit.

Is this possible? I know that a hacked PSP can do it.
1 posts omitted. Click Reply to view.
Jenny Clammerfork - Thu, 27 Mar 2014 21:32:21 EST ID:FABnkK5n No.6234 Ignore Report Quick Reply
How do I record each code and assign it manually?
John Blenderlune - Fri, 28 Mar 2014 22:44:02 EST ID:vXg79lPA No.6235 Ignore Report Quick Reply
You need a microcontroller and an IR sensor. And an IR LED. And a power supply. And some very minor signal conditioning.
Frederick Depperhall - Sun, 30 Mar 2014 01:41:43 EST ID:xZgv+GY1 No.6236 Ignore Report Quick Reply
do you have the original remote?

if you do you can press the button and receive it in the other end with a circuit

the circuit is kinda involved, but it's easy if you're willing to learn

basically the signal is gonna come in as a square wave and you're going to have to grab that bit by bit, and turn in into a word, how ever long it might be.

i can't imagine the remote outputting more than 16 bits of information per button but i could be wrong, testing something like that might require an oscilloscope, but you might be able to find one at a hackerspace or something

to turn it bit by bit to a word you need something that's called sipo shift register which stands for serial in parallel out shift register. you might need a clock for one of those as well, and the clock speed might need to match the speed of the remote output though if you're clever you can get by that with a microcontroller or some clever circuitry but i'm not getting into that

and the output of that goes into a data buffer
Comment too long. Click here to view the full text.
Basil Dezzletig - Mon, 31 Mar 2014 08:38:40 EST ID:+llB3/RB No.6237 Ignore Report Quick Reply
1396269520444.jpg -(197292B / 192.67KB, 564x423) Thumbnail displayed, click image for full size.

There is a lot of various circuits
Simplest build is like 5 parts
Software will take care of the rest
Sidney Clenkinweg - Tue, 01 Apr 2014 13:51:36 EST ID:DPsZhwc3 No.6238 Ignore Report Quick Reply
Well I give up.
Thanks anyway though!

Chinese 60 years behind the space race by Hedda Creffingdock - Mon, 10 Feb 2014 09:18:46 EST ID:9tRAlAIb No.6126 Ignore Report Reply Quick Reply
File: 1392041926891.jpg -(282326B / 275.71KB, 752x1063) Thumbnail displayed, click image for full size. 282326
Why did the Jade Rabbit moon rover fail /tesla/ ;_;


Trap card: Most of the Chinese engineers who developed it would have got theirs Masters and Docotrates from American Universities. I'm looking at you, Cal-Tech. and UCLA
Hedda Creffingdock - Mon, 10 Feb 2014 09:20:18 EST ID:9tRAlAIb No.6127 Ignore Report Quick Reply
1392042018891.jpg -(6456B / 6.30KB, 292x172) Thumbnail displayed, click image for full size.

*their Masters and Doctorates in Engineering from American Universities
Archie Buzzman - Thu, 20 Feb 2014 20:29:42 EST ID:Oq2QBNL1 No.6152 Ignore Report Quick Reply
why would they make a robot, powered by sun light, that can not turn on when its solar panels are collecting sunlight?
Graham Honeyman - Fri, 21 Mar 2014 22:38:15 EST ID:nSEO9O+z No.6222 Ignore Report Quick Reply
>During this time temperatures plunge to -170 degrees Celsius (-274 degrees Fahrenheit) and Jade Rabbit – which is powered by solar panels – must enter into a hibernation state to preserve its core systems.
Why the fuck would extreme cold hurt it? Preserve it's core systems? The dragon that powers it? Can't it boot up again after gathering energy after the lunar night?

>"If this journey must come to an early end, I am not afraid. Whether or not the repairs are successful, I believe even my malfunctions will provide my masters with valuable information and experience.
Yeah, maybe not to write half assed buggy software next time? Just making guesses...
Augustus Dummermetch - Fri, 21 Mar 2014 23:04:23 EST ID:5IdDtd2q No.6223 Ignore Report Quick Reply
space grade dragons and electronics alike are usually just not made to resist those low temperatures. or should i say, resist very low temps too good? get it?
Hugh Chosslefield - Tue, 25 Mar 2014 11:01:01 EST ID:TLtnKWTx No.6231 Ignore Report Quick Reply
I feel bad for the midged inside

Metal Wire Coating by Ernest Pockville - Sun, 23 Mar 2014 14:28:35 EST ID:uEfymhfr No.6224 Ignore Report Reply Quick Reply
File: 1395599315823.jpg -(42328B / 41.34KB, 600x509) Thumbnail displayed, click image for full size. 42328
I'm trying to connect two different USB cords together, but one of them has this metal coating.
Is this a 5th contact or what does it do?
Shitting Pammerman - Sun, 23 Mar 2014 23:16:50 EST ID:2POYse6P No.6226 Ignore Report Quick Reply
it's the ground.
Nigger Nonkinnatch - Mon, 24 Mar 2014 01:06:26 EST ID:uEfymhfr No.6227 Ignore Report Quick Reply
Sir, I think the black wire is the ground
John Dartfield - Mon, 24 Mar 2014 13:47:20 EST ID:gxnGDEmu No.6229 Ignore Report Quick Reply
it's the shielding which is connected to ground?
that stops radio and other signals from interfering
Nigger Nonkinnatch - Mon, 24 Mar 2014 14:16:11 EST ID:uEfymhfr No.6230 Ignore Report Quick Reply

Space Station 13 by Lillian Beblingdudging - Thu, 05 Sep 2013 06:09:36 EST ID:qcML6joZ No.5879 Ignore Report Reply Quick Reply
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There is so much engineer in this game, I don't think I've seen so much engineer in a game since Team Fortress 2.

So much engineer, so many Practical Problems.
Priscilla Turveyville - Mon, 09 Sep 2013 21:35:02 EST ID:KFZ9rgNf No.5889 Ignore Report Quick Reply
Doris Dartworth - Sun, 16 Mar 2014 09:09:46 EST ID:RG6LVbQe No.6221 Ignore Report Quick Reply
420chan now has its own SS23 server.

So Engineer
very practical problem

Forced semester off, can study ahead online? by Edwin Ferryshit - Thu, 13 Mar 2014 22:27:21 EST ID:9+I+k5VX No.6216 Ignore Report Reply Quick Reply
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Hey /Tesla/,

I was taking Calculus and CS courses last semester, but was suspended from registration due financial issues. These were both prerequisite classes for my intended major.

My question is are there any websites or libraries besides Khan academy that I could use to study Physics, Statics, and or Heat dynamics?
(Preferably with proper notation and formula.)
Isabella Gemmerson - Thu, 13 Mar 2014 23:31:52 EST ID:CKZoWqYh No.6217 Ignore Report Quick Reply
MIT has a lot of open course material
Augustus Sombleford - Fri, 14 Mar 2014 18:40:42 EST ID:gJ2Omk9E No.6219 Ignore Report Quick Reply
Personally I'd study the textbook in advacnce. Find out what textbook the instructor uses.

Logging Circuit by Walter Daffingwell - Thu, 13 Mar 2014 03:13:51 EST ID:4fpX8pqx No.6210 Ignore Report Reply Quick Reply
File: 1394694831517.png -(3606B / 3.52KB, 118x44) Thumbnail displayed, click image for full size. 3606
I wouldn't know where to begin here, but I need to log the opening of a small door.
So I could have some kind of circuit, and there would be little metal contacts on the door and the hinge, then whenever the door is opened -> circuit broken -> log that somehow.

Does anyone know I could make this logging device?
Nigger Cheffingville - Thu, 13 Mar 2014 21:01:18 EST ID:2POYse6P No.6215 Ignore Report Quick Reply
arrange it so when the door is opened, a lever moves and presses down on a key on a manual typewriter.
OP - Fri, 14 Mar 2014 11:08:49 EST ID:4fpX8pqx No.6218 Ignore Report Quick Reply
While that would get the number of opens, what I'm looking for is the time/dates of them.

I've done this by setting up a webcam that activates when it detects motion.

fucking smps - how do they work? by Anonymous - Sat, 22 Feb 2014 19:18:54 EST ID:kU/b2Op8 No.6154 Ignore Report Reply Quick Reply
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hi tesla,
i'm building a led panel with integrated fan and don't know how to run a pc fan from the same voltage source. the fan is rated 12V @ 450mA, the supply does up to 1A and has 5V left after the leds. the fan needs probably 2A at startup and it should also run when the leds are off.

a switch mode dc/dc converter seems a good idea. it should boost the 5V to somewhere between 6 and 10 V and also deal with the excess voltage when leds are turned off, ie. short circuited via dpdt switch. a look at wikipedia tells me buck-boost or sepic converters can do that.
downsides, what to watch out for? don't most those converters hardly work in parallel?
are there alternatives? a zener would be enough to limit the volts but only with an ohmic load.

i want to learn the basics and take a closer look, just asking if i am headed in the right direction basically.
7 posts and 2 images omitted. Click Reply to view.
Cedric Diblingbanks - Sun, 09 Mar 2014 00:21:19 EST ID:kU/b2Op8 No.6202 Ignore Report Quick Reply
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Working in a simulator I could prove my idea in principle. This is just a modified example circuit that comes with LTSpice having 5V 440mA on the output. Integrating the input over a low-pass and subtracting the low-pass resistor voltage drop-off 36V 80mA appear to be stepped down with 83% efficiency. great success. The voltage breaks down over 1A, though.

... was quite happy to see at least some results. Now i am eager to advance this to incorporate a microcontroler to schedule the light, log and regulate temperature, i even found cheap humidity sensors.


The resistor is supposed to limit the input current to be collected by the cap and given to the switcher in very short high current bursts.
At startup it still takes almost 1A leaving none for the LEDs.
Trial and Error brought me to this setup using another low-pass at the gate of a mosfet, that switches on when the cap is sufficiently loaded. I tried to increase the slow start effect using an Inductance. The usefulness is questionable. A mA ringing with the cap happens for microseconds at startup - through the MOSFET. When tested separate from the switcher it's gone! Simulation without the inductance fails because the calculation exceeds memory, WTF? Same if only one of the Motors represented by each RCL network to the right is used.

My approach is a million monkeys on a typewriter. I tried a few example test circuits before one was found that worked with different input voltages. The output voltage is below my requirements and i am dumbstruck. I think the voltage divider over the feedback pin needs to be adjusted. Instinct tells me that's not all there is to it. That's why I am hesitant to test with real components. Is the simulation close enough to reality?
What components anyway, capacitors have a series resistance? at least LT Spice has a datafield for it, but that was left empty.

The lt10xx series is supposed to be as simple to use as an lm317. lm317 is not exactly a piece of cake either. there is tons of material on this subject but i don't have the foundation, e.g. impedance or power factor calculation to work on it.
Sidney Sollernack - Sun, 09 Mar 2014 03:37:13 EST ID:vXg79lPA No.6203 Ignore Report Quick Reply
>Integrating the input over a low-pass and subtracting the low-pass resistor voltage drop-off 36V 80mA appear to be stepped down with 83% efficiency. great success. The voltage breaks down over 1A, though.

Where is this 36V coming from? I thought your power supply was only 12V. And what's the point of the RC in front of the switcher? The resistor is only going to burn current that's used by your fans. And of course the voltage breaks down at 1A. One Amp across a 36 ohm resistor is 36V. At that current, all of the voltage is dropped across the resistor. It's not like your power supply can output that much voltage and current anyway.

>I tried to increase the slow start effect using an Inductance. The usefulness is questionable.

If you want it to start up slower, why wouldn't you just increase R8? There's no need for the inductor.

>The output voltage is below my requirements and i am dumbstruck.

The output voltage is 5V according to your graph. The LT1076 has an output of 5V. It's a 5V step-down regulator. What else did you expect?

It sounds like you're trying to build a space shuttle to pick up the groceries.
Cedric Diblingbanks - Sun, 09 Mar 2014 15:52:51 EST ID:kU/b2Op8 No.6204 Ignore Report Quick Reply
1394394771532.jpg -(77825B / 76.00KB, 1024x768) Thumbnail displayed, click image for full size.
>Where is this 36V coming from? I thought your power supply was only 12V. And what's the point of the RC in front of the switcher? The resistor is only going to burn current that's used by your fans
The PSU is 36V, Vout is the regulated 5V.
The powerloss of R5 is only 0.2W, no biggie. The current spikes on the switcher input would be way too high for the psu, judging by the specs. Although the supply might withstand that, i am not gonna risk it. the capacity of the filter was chosen randomly. if you criticized that, i would understand. tips for choice of the the cap would be welcome, there are so many types and i need them rated for the voltage and ripple current,

12V on the fan would be nice to have, but it should run with less and quieter at that.

>If you want it to start up slower, why wouldn't you just increase R8? There's no need for the inductor.
Don't want the rise time of U_DS too high. Don't know if it really matters.
>It's a 5V step-down regulator
No, this is a lt1076. You might think of lt1076-5. That one i didn't know, it's interesting.

I am still concerned if the switch topology is suitable. There's so much more to learn and this project gives me a reason to explore.
Jarvis Faddlekane - Thu, 13 Mar 2014 02:50:50 EST ID:NimfZmq9 No.6209 Ignore Report Quick Reply
admittedly, it's written a bit confusing. first i didn't understand myself when i just reread.
The resistor in front of the switcher IC has to be at least 36 Ohm so that the current is limited to 1A, because else the voltage might be cut off by the overpower protection of the PSU.
nb because you show not much interest
Archie Simmerkadge - Sun, 23 Mar 2014 15:54:37 EST ID:kahK/jZ9 No.6225 Ignore Report Quick Reply
The fan needs volts to start not amps
Some 12volt fans do start on 5volt you might consider getting one.

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