Hey have 66 lead acid batteries to play with, I'm thinking of making a shitty electric car. What would you do wit too many 12 volt battery.
They were used as a backup power supply for a casino, maintained well enough. I
don't really know what I would do with so many
>>920603
Bomb proof home backup system?
You probably use 5kw/day at most and assuming I lowball the batteries (50 usable batteries * 70 Ah * 12 V * .80 % efficency) you'd have around 35 kw of energy to use and I'm really lowballing this. You could use the rest to make a kickass car or a really strong welding setup. I'd talk to someone who does home backup/solar stuff.
>>920601
I'd use it as part of an off the grid electrical system for my house (48v 1283.7aH in series-parallel ), until they died in around the 5 year old mark.
How old are they? They might be worth more just as scrap. If so you can make a DC stick welder out of them or a furnace. Make an electrical car or a few electrical gokarts. They'd be great for one of those solar-powered Elf vehicles/bicycle hybrid things. There's lots of plans online for similar vehicles.
https://www.youtube.com/watch?v=pQQzLMIXOJ0
Hi /diy/. I'm doing a capstone project next year for my last year of mechanical engineering, and I'm having trouble thinking of what to do, so I was wondering if creative minds such as yourselves could throw some ideas out there.
Here's what I know: mechatronics (microcontrollers and whatnot), cars (very well), machining, PID control, and other basic engineering stuff.
Like really I'd like to make something with a humanitarian purpose or could be turned into a business idea, but if you had an idea like that then you'd be doing it yourself haha.
remote control vibrating dragon dildos for quadriplegics,
How to read Ms Universe cards for dummies.
Or
An idea generator
An actually affordable assistive exoskeleton using 3d printed parts for people who have limited mobility? (Possibly feeding from a wall plug so they can at least walk around their home, unless battery issue can be solved)
A better voice modulator for throat cancer patients that doesn't make them sound like a dalek? (Not sure if that would fall under your area of expertise)
A portable, but still effective jaws of life system (think small enough it could be tossed into a glovebox or doorwell of every car) to avoid waiting for emergency services in a critical situation (potentially dangerous for untrained, possibly include warnings on casing)
Possibly some form of hydraulic "talon" to be mounted underneath a vehicle in case of brake failure in cold and icy weather? Something that senses when the car is still sliding and goes "fuck, time for plan c"?
Let me know if I'm remotely close to the mark or way off, I'll think of more. Have not done anything with mechatronics and am certainly not by any means an expert.
Hey /diy/, need some input on what the best way to handle this situation is.
The connection to my car's battery is really spotty.
I've never seen battery terminals like this, and they're rusted so bad that they pop off of the battery leads. Anything I should know before I commit to desperately sawing them off and soldering on a new set?
There's a 3rd small cable coming off of the positive lead too, dunno if that's supposed to be the ground or something unrelated.
>>920295
Hack em off, clean off the corrosion, then just bolt a new pair of terminals on.
They sell bolt on ones everywhere, like walmart and stuff
So its as simple as it sounds then? Alright I'll give it a shot, thanks Anon.
>>920295
No to the solder. Like the other anon said, they sell bolt on ones(basically what you have) that you can tie every thing back in on. The extra wire coming of the positive is absolutely not a ground. Ground will be the negative. Don't change any of the wiring unless you have to, run it exactly how it is. That other positive wire probably runs to the back of your alternator.
Some of the new cable ends come with spots to clamp down smaller wires, some do not. If the ones you get do not you'll need some crimp connectors, the eyelet ones. They'll need to be the right size for the bolts on the new battery connectors. Crimp one on a smaller wire and slip it into a bolt before tightening it down.
This is an incredibly straight forward job, but it can be intimidating because of the amount of wires some cars have. The oldest mechanic trick in the book(aside from saying your head gasket is bad) is to only do one side at a time. This way you make sure a positive doesn't wander over to the negative clamp. That trick works for anything from drum brakes to cabinet doors, either as a point of reference or to make sure parts don't get mixed up.
Before committing to this though, a Re you sure it's the battery connections not a broken/rusted ground somewhere. One thing you can do to test, which can be very dangerous to you and the Car if done wrong, is connect jumper cables from the battery cables to the battery. If you have a completely solid connection but the problem persists it in plus the connectors are good and the problem is elsewhere. This is dangerous because it's incredibly easy to create a short. Only do this if you feel you can properly isolate the jumpers from each other and the cars chassis, which is where the ground runs to.
Do any of you have a clue what this would be? Installed in a 1920s home in the U.S., about 4" diameter. Fastened to the door between kitchen and dining room.
Asking multiple boards. Nobody seems to know yet.
It look like a vent for a smoker, perhaps it was just decorative?
>>921436
> Fastened to the door
> Has Open and Closed written on it
Looks like a strange doorknob to me. Does it connect to mechanisms inside the door, or is it just a non-functional piece of metal bolted to the wood?
>>921437
This makes sense. Looks like it could have been a check valve.
Where can I buy a big bag of used padlocks to practice picking? Don't care about keys, just quantity, variety and low cost.
Thrift stores, Craigslist, garage sales.
Bike racks
>>920633
Go find a nearby bridge, people love to lock bridges.
hey /diy/, i got an electronics 101 question
connected a 3V battery, a 100 Ohm resistor, and a green LED in series. expecting I = 3 / 100 = 30 mA
connect an old "Fluke 29" multimeter, and it's current measurement reads "06.75 DC" (assuming it means 6.75mA)
am i doing something wrong, is the multimeter bad?
>>919638
Coin batteries have very high internal resistance, it's like you've put the100 ohm resistor in series with it. To calculate it short the battery with the ampmeter, then divide the voltage by the current measured.
You're doing the math wrong. Using I=V/R like that gives you the current that would be going through the resistor if it were connected directly across the battery with nothing else in the circuit.
The purpose of an LED series resistor is to produce a voltage drop so the LED gets the recommended voltage. When the LED gets the recommended voltage it will draw the recommended current.
If the LED is 3v 20mA (0.02A) and the supply is 5v then you need the resistor to drop 2v. Vdrop = R / I = 2v/ 0.02A = 100Ω. Putting a 100Ω resistor in series with the LED will make the LED get 3v from the 5v supply. The current through both the resistor and LED will be 20mA.
I'm assuming your green LED is 3v, so it's going to get the correct voltage from the 3v battery and draw the correct current without any need to produce a voltage drop with a resistor.
>>919660
sorry, i should've been more specific. my 3V battery is actually two 1.5V AA batteries in series.
when i short them with the ampmeter it reads 0 on its "10A" setting and OVERLOAD on its 40mA setting.
Hey /diy/ .
I found one glove in the metro the other day.
Good quality leather and very softy fur.
Now, I only got one and I thought I could make something out of it, but couldnt realize what.
I thought i'd take the fur off so i'd make another item, and that i'd use the leather as knives sheath but that's pretty much all my imagination was capable of.
Any idea ?
>>919116
You didn't take it to lost and found so you're basically a thief.
I think i saw an instrucable on how to make little teddy bears out of them...
>>919116
A large condom for Eskimos.
need help with 3.5 inch LCD that connects to raspberry pi 2 b+ the drivers are kinds of of fucked up
3.5" LCD screen driver, pls click the link: http://osoyoo.com/wp-content/uploads/samplecode/raspberry_35_inch_ts.rar
3.5" LCD screen instuctions, Pls click the link: http://osoyoo.com/wp-content/uploads/samplecode/rasp_lcd.pdf.
Raspberry Pi 2 instrction: pls click the link: http://osoyoo.com/wp-content/uploads/samplecode/rasp_os.pdf
Howdy,
i am trying to identify this broken SMD Part. It was on the pcb of a fluke 87 IV i got for free because it had suffered falling damage. I already identified a broken smd resistor but i have no clue what this thing could be.
Looks like a resistor. See if you can measure the broken parts with another meter.
>>921130
Is there any part designation on the board? If so, you could try calling Fluke and asking what that particular resistor on that meter is.
No Parts designator anywhere on the board. And since the part is broken i cant measure anything, even if i push the two halves together very hard.
What is the best way to cut a hole into the BOTTOM of a bottle? Needs to be about 2-1/2 inches in diameter, just big enough to fit a light bulb
Do diamond hole drills that large exist? I can't seem to find one anywhere. And those compass glass cutters never seem to be small enough for the diameter I need.
You can get 2 1/2" diameter diamond bits on Amazon.
drill a hole in the very center, stick a toothpick in it, tie a string around it and attach the other end to a glass knife, score the glass in a circle. I don't know if this will knock out easily, but you can always get a very small diamond drill bit and cut small holes all the way around the circle, then try to pop it out. Then you can sand the edge smooth. Sounds like a lot of work though.
>>920642
This is a great idea, thank you. And it took forever to find that 2-1/2 inch drill bit on amazon, but I did find it. I think I'll take the expensive and easy route instead of the cheap-but-hard route and buy the bit, lol
hey everyone.
i'm trying to build a communication system based on infrared LED and receptors.
the speed will vary from 480Mb/s to 2.4Gb/s. (480Mhz - 2.4Ghz)
can the system handle those frequencies ?
thank you
The IRDA ports from the 90's never caught on because they were so unreliable. They operated at 9600 baud, which is literally millions of times slower than what you're proposing.
Look at the datasheet for the IR phototransistor you want to use. It should have parameters for how quickly it reacts. That will be the maximum bit period possible.
>>920332
* minimum bit period possible.
>>920332
>The IRDA ports from the 90's never caught on because they were so unreliable
i understand, but they were unreliable because the transmission was bad.
i beleve fiber optics use the same principle (light) to transmit data. thats what i intend to do.
i just want to know if the regular IR devices available can do the same
Is lock picking /diy/ ?
>>913952
>What is hobbyist picking?
Fuck off retard.
>>913960
Chances of you wanting to be a hobbyist picker versus chances of you being a 14 year old edgelord from /b/ are rather low.
Get a keychain set. They work as good as any and you'll have them on you when you want to impress that girl with the piercings at a party. Wear a condom.
>>913965
This. We've never had a honbyist picking thread. Its always some nig nog trying to get into crime
Do you guys have any ideas for assembling gift packages? My friend and I are planning on sending some to eachother but I'm not sure what they'd like.
Does anyone else here like assembling them?
What type of stuff do you find works the best?
What exactly are you asking? What kind of gifts you should give your friend? How the hell should we know? What does your friend like would be a good start. Do they like video games? No? Don't send them a video game. A Gail safe gift would be a blow job, send them one of those.
I thought /diy/ might enjoy some nice handiwork
ITT: Korean Canadian builds a shed using unconventional techniques. First step: framing
P.S. if this has been posted before tell me to fuck off and I will
Highly skilled craftsmanship
First car, trying to decide what I do or dont need in the trunk.
I had a shortbed regular cab truck with not much room so I kept nothing at all in it.
Whats in your trunk?
From tool kits to survival bug out shit, looking for ideas.
extra jug of washer fluid, extra wipers, jumper cables, and a roll of duct tape for road side auto body.
A fire extinguisher and some gloves.
Tarp, bleach, paintroom plastic, ammonia, gloves, masks, spare license plates, and some handy knives and blades.