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i have an old 1980 honda bike i picked up that has a cdi system and no spark. there are 2 suspects in this: the cdi unit itself or the magnetic pickup that tells the cdi when to fire. there is a testing procedure and the only fault ive found is that the pickup coil is 60 ohms under spec (147 instead of 207) so it may not be making enough of a signal for the cdi to see and spark. there is no testing procedure for the cdi box because 80s japanese space magic, the only way to test it is to eliminate everything else. ideally i would just replace the pickup and try again, but for some fucking honda decided to integrate it with the stator harness and only sold it as an assembly so now there are very few parts floating around and they are very very expensive. so i basically have 3 options:
>buy a new stator assembly and hope the cdi box is good, if not spend even more on that
>buy a used cdi box and hope it works or get disappointed and left with another working $150 part
>build an amp for the trigger
>make my own ignition system
i got the bike for $100 and its in rough but complete shape, so im really not about to go spend 6x the value of the bike on 1 or 2 parts. number 3 seems feasible but i dont know how i would go about that or if it would even work since no one knows how the cdi even reads the signal, so boosting it might not even have an effect. im really leaning towards number 4 because a 12 year old can follow transistorized ignition plans online, really the only issue i think i will have to work out is how i will trigger it because i have no idea how to do that with a magnetic pickup system. it would just need to react to the pickup firing to cut the transistor thats powering the coil to induce a spark, and it would need to be fast enough to work up to 10k times a minute (10k rpm redline).
can anyone give me some guidance on how to accomplish something like this?
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grow a pair, you don't need a manual to tell you what a fucking magnet passing a fucking coil does.
the signal is a pulse, typically more than half a volt but less than twelve.
set your multimeter to ohms, ground one probe, poke the CDI sense pin with the other probe, observe the spark at the plug.
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>>1198236
If you're getting less coil resistance than expected, the windings are shorted. Epoxy breaks down, vibration knocks shit apart, temperature fatigues the materials.
What i'd do ... buy a spool of magnet wire, carefully unwind and note which direction the windings go (That may be a 3-phase coil, so you'll have 3 wires/6 ends to deal with, and probably another for ignition). Wear gloves when you unwind it, the old wire is like handling razor wire.
Then rewind the coils.
CDI module is kind of hard to bench-test without equipment. I'd start with the easy stuff like the coil first, then if that still doesn't work, replace the CDI.
Something that old, you'll probably want to rework the stator coil anyways just for reliability even if that's not the issue.
Ohm out the wiring harness too.
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Can anyone point in the direction of a comprehensive guide on bending copper tube in 15mm & 22mm?
I'm going to be replacing my bathroom soon and I would like to utilize as many bends as I possibly can.
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pain in the dick to get right, especially without a lot of practice. I've never done it, but I bent plenty of EMT over the years installing systems in my houses and for friends.
Soldering is really easy, and lasts just as long. Might want to consider it
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>>1198235
You usually don't the copper will be weaker and thinner at the bend. If you were just fucking around doing art or something I get a tubing bender and some sand. Put sand in tube and bend away.Keeps it from buckling.
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>>1198240
I'll be soldering at some points, where I have no choice, but I would like to use bends where I can.
I'll be having to bring the hot and cold feed over the waste pipe for the sink, so it's either a pair of passover bends or using 8 elbows, which would just look ridiculous.
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Useless person here and suck at knowing how to do stuff. Can anyone tell us how to fix this? At the bottom of a cheap door
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From a dog scratching it
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>>1197912
make it a little smoother and fill the gap with plaster
or just smoothen and paint over
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>>1197912
If you have a dog your best option might be to install an aluminum plate on the door. It will cover and prevent further damage.
To fix it you could try sanding it a bit, applying filler and painting it white, maybe you can use use a fork on the filler to emulate the fake grain. Paper doors suck and will probably get damaged again.
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Why this homopolar motor does not want to work?
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>>1197806
There is no way a Lorentz force can be applied on your magnet retard
Must be bait
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>>1197807
Sorry, but I don't know anything about it, what am I doing wrong?
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>>1197814
Excuse me for even suggesting the possibility of such an inconceivable fault on your part, but did you by any chance not even try looking it up? Once again, sorry if I sound like I'm implying that you're utterly incapable of independent thought or problem solving, but I assure you I am not. I am simply bringing up the highly improbable possibility of you skipping that one step due to your rightful confidence in your unparalleled knowledge of physics and certainly not because you're a mouth breather. Surely, a problem such as this - a problem that not even your special mind could tackle can only be solved in the most prestigious of scholarly circles. And I am truly humbled that you've graced us with your light and permitted us to follow you in your endeavor to untangle this incomprehensible enigma of science.
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Recently, I got a hold of some Sherline machine tools. It's a Model 2000 milling machine, and Model 4400 lathe, with all the trimmings. I think it was bought as the Model 6000-DRO Ultimate Machine shop package. http://sherline.com/product/6000-dro6010-dro-ultimate-machine-shop-package/
There is also a second Digital Read Out display, which goes for about another $250, and a cart (shown) which I actually have a reciept that it cost $160 in 2008. (I'm assuming it was all bought pretty much together.)
I'm trying to sell it, and I have no idea what I should charge. They're very lightly (read: BARELY) used machines, and they come with all the trimmings. I did some quick math, and it's almost $3700 worth of tools new. What do you think is a reasonable price for these? I know just about nothing regarding the used machine tool market.
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The lathe
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>>1197456
Sherline is in a weird spot for machine tools. way more expensive than the hobo freight chink mill/lathe but not quite as expensive as a used bridgeport. most people will either spring the little bit extra for the bridgeport or go turbo jew with the HF stuff.
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>>1197456
>not keeping them and doing some machining
Put it on craigslist and ask for trade offers
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I'm trying to create a vacuum chamber, with a chamber that doesn't have a perfect seal and I can't replace it. Using a small pump, I need to maintain a vacuum of about 20 mmhg, accurate within about 5 mmhg (15 to 25 mmhg) at a given time.
I'd prefer it if I could rig a regulator of some kind to control the power of the pump. The only thing I can think is to create a regulator out of a syringe, rigged to a linear potentiometer that powers the pump, but I'd like some suggestions before I try anything.
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>>1196779
This is usually done by using a valve to throttle the pump line or bleeding air or some gas into the chamber or both.
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>>1196783
Yeah, but that's pretty energy inefficient. The chamber leaks very slowly, so there's not much of a point to leaving the pump on non-stop.
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>>1196779
So fix the fucking seal you mongoloid. Jesus Christ...
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Hi guys,
Lately I've been tinkering around with homemade scuba gear. Making the tank and some sort of push-operated airflow Regulator is pretty easy. But I'd like to build one that is, just like a commercial regulator, activated by breathing in.
Does anyone have an idea on how to do that in maybe an elegant way?
I've found this video:
https://www.youtube.com/watch?v=Yktilms-Tck
it's in russian and the guy seems to be building some kind of breathing-activated regulator. I don't know what the round valve thing he's using is though, any pointers would be much appreciated and if someone could tell me if that Thing works for him in the end it would be nice, too.
Thanks in advance and looking Forward to some discussion about the subject.
P.S.: I know that this is very dangerous and rest assured I would not be using it to do any actual diving. I'm just facinated by the concept of maybe doing that myself. I'm a certified diver and thus I'm aware of the dangers of homemade gear in any significant dephts. Thank you so much for your consideration and I'd be happy to hear about your safety concerns aswell, of course.
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I'm not normally one to advocate buying shit, but in this situation just buy it mate. It's your fucking life on the line.
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Well, even on the surface, if your regulator valve fail you get your lungs literally btfo by high pressure gas from the tank.
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In the early 60's people used old fire extinguisher bottles for tanks
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Water will not drain from garbage disposal. Just moved into a house and have never used one before. What am I not doing?
Thanks friends
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>>1196345
Poor liquid fire in
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Draino, if that doesn't work then shut your water off and take apart the plumbing to try find what's going on. Most of the time it's just food gumming up the pipe. If your still at a loss then maybe find someone who knows what they're doing.
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>>1196351
The strange thing is....it does not look clogged. Its like there are no holes in the stopper. So impossible for water to drain. Do I pop the "stopper" out or something? Pipes seem clean
Anonymous
Shop Vac Attachments REEEEEEEEEEEEEEE 2017-06-19 03:38:05 Post No.1195983
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Shop Vac Attachments REEEEEEEEEEEEEEE 2017-06-19 03:38:05 Post No.1195983
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Shop Vac Attachments REEEEEEEEEEEEEEE
Anonymous
2017-06-19 03:38:05
Post No. 1195983
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Why is it impossible to find adapters to hook up a shop vac to power tools?
I want to hook up my miter saw, which has a 2.5 inch dust port to my Shop-Vac 5986000 which has a 2.5 port on the unit and a 1.25 hose end. I've looked everywhere but all I can find are adapters that are the exact same diameter as what I'm trying to connect them to. It's like the entire industry is in cahoots to make this impossible. None of them even use "male to female" or "female to male" language to make it possible to make sense of anything they sell!
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duct tape nigger
pvc pipe to make quick connectors
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They'll usually fit without a problem with a shopvac made by the same manufacturer as the tool... they want you to buy theirs.. but yeah as other guy says... duct tape.. or for small diameters those rubber plumbing fittings with a hose clamp on either end work pretty well...
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>>1195983
use cut sections of bicycle inner tubes
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So I have a great friend thats a hoarder. We exchange favors often yet he always expects me to help move truck loads of shit to storage units because he helped me with something trivial. We spend two days clearing his house to have it filled up again in a month. If you try and discuss it he gets mad and throws guilt trips. WTD? His wife and kids are miserable. Ironically the guy is a genius....and alot of fun to be around. I'm the exact opposite with regards to hoarding, I'm very organized...Frustrating...If I didn't like the guy I'd tell him to fuck off ...Pic not related but relative
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>>1194678
Your pic is acceptable level of hoarding, at least it is clearly organized, kept clean, and the plants taken care of, which would make it healthier than an empty room
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>>1194678
It's an addiction OP. It's not going to change until he wants to, and nothing you do or say can make him want to.
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Instead of taking the junk to a storage unit just throw it out?
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Can you help me...it's regulator for a train.
I cant make it not burn when its complete like on high scheme. When its like on low scheme it looks like everything is ok. Its rated 4Khz, cause LM358 cant do more narrow edges at 11V levels. I was also trying to pwm just high side, and turnong off/on low side when needed. Didnt helped.
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Your gate signals must be with referenc to aource.
Here your gate signals for high side fets are with reapect to gnd, this means that your gate will most likely see a voltage higher or lower than 20v, this destroys the device.
Look for a half bridge mosfet driver, use one for each side of the H bridge.
When you build the new circuit, use 10-30ohm reaistors in series with the gate. Layout should keep area between wires small.
Use decoupling caps, film and electrolytic for the bridges, and ceramic for gate drive.
Any parts that does not makes, try google, or begin with a less complicated version of the circuit.
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>>1194115
Thanks for responding.
I will try with resistors for gates, but where exactly should i put these caps? I got one 100uF for Vcc.
With voltages from avr uc it didnt opened or very small open, not enough to move 12V motor. I power this with liion pack, whatever 9-15V, now its about 11-12V. Signals for ure arent higher, more like at 11-10V just like IRF datasheet says.
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>>1194075
This configuration may work with bipolar transistors but not with MOSFETs because the upper part has not enough gate voltage. Please read (to the end):
http://www.talkingelectronics.com/projects/H-Bridge/H-Bridge-1.html
There's a link about how to avoid such errors.
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I was thinking of creating my own sort of fume extractor so I can smoke in bed instead of standing by my window.
Essentially, the fan would go right up against the screen, so the smoke would be drawn in through the intake and pumped outside. I would attach a funnel over the intake side of the fan and seal it somehow, then attach a long-ish rubber hose to it and attach another funnel on the other side.
Is this viable? If only I was allowed to smoke in my apartment building I wouldnt even be having this problem.
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How much of a fat degenerate must you be to have this problem? You're a future dummy who falls asleep with a cig and immolates himself and innocents
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>>1193660
I want to be comfy while I get high after a long day's work, fucking sue me.
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>>1193657
gonna need a better fan, think of something like an attic fan. they are cheep and effective
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Hey /diy/, I've got an idea to build an electric guitar with a "secret wood" body. You often see these types of designs on rings like in the pic related.
I was wondering how I could do some of the more "complex" patterns and designs like this snow storm or the aurora borealis posted below. I'd imagine it'd be something to do with mixing epoxy only partially but is that it? What type of epoxy(s) should I use for something as big as a guitar body? I've never worked with resin before so I'll definitely do some tests before I commit to anything big.
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notice the sort of "fallen snow" and bubbles simulating snow that's still falling. I think that'd be cool to do in a guitar
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hi guys, anyone knows where i can buy some of these? i don't know its name but i need them
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What is it's function. If you don't know the name then describe what it's used for
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>>1198143
didn't you post this weeks ago? and you still don't know what it is?
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>>1198154
yes, i know what it does, i just can't find them
its a fiber optic connector
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You have to live in NYC for a year so you can only fill this toolbox with what you want to do all the /diy/ related things you want to do.
What do you fill it with?
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>>1197975
Money.. otherwise you'll spend 10 months homeless in New York....
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>>1197979
>money
This is the only viable answer. Even a large toolbox wouldn't fit a small fraction of my tools in it.
Hell, the air compressor alone would fill it. And how the fuck am I supposed to run my plasma cutter without the compressor? (Nitrogen bottle doesn't count.)
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>>1197992
So you can't do heavy duty metalworking, so be creative What do you fill the toolbox with to have the most /diy/ fun when living in a shoebox?