Question regarding speed electricity

Hi people! I have another thing which i do not totally understand, so as usual i have asked in one of my favourite sites! :) I always had a doubt on how "fast" is electricity. In our real world, i can observe that it is pretty fast. If i turned on a switch connected to a light bulb, i can see it turned on pretty much "instantaneously". So a question came to mind, how fast it really is? Is it near to the speed of light? So, i did some googling. According to what i have found and understood so far, it is the electric field that carries information and not the electrons themselves. And electric field travels near to the speed of light( of course, depending on the medium).  If that is the case, then from the "textbook" definition of electricity, it is the movement of electrons right? But according to what i have understood so far, electrons move pretty slowly. In DC a few millimeters per hour or so(not having the exact figure in mind, pardon me) and the average displacement in AC is zero. Then how exactly is electricity so fast? I would appreciate it if someone explains it in a simple way, both on speed and what exactly is movement of electrons. :) Update: Okay, so far my questions are answered, and it seems to take off in different directions(like science always does :D). So to stay true to the question posted here, i would like to say my doubts cleared! Many thanks to people who have answered my question, Specially Dr.Kelsey and Josehf , for the information provided! I will post other doubts in new topics.

Topic by charmquark   |  last reply


AC motor speed controller for stereo turntable

Hello Brainiacs, I am wondering about salvaging a electric fan speed controller for my Vintage (1980's) Stereo turntable. I purchased a table from Europe and it ran on 50Hz 240v. But once I rewired the unit for 110v 60Hz it still ran too fast. It is a synchronous 24 pole motor driving a small pulley and belt system. I was told a speed controller would fix the issue by varying the voltage. True? Or if someone could come up with a schematic! ??? Any suggestions? 

Topic by bullit224   |  last reply


0.3mm nozzle printing speeds?

I am currently finetuning my homemade hotend and was wondering what you guys have in the speed settings for 0.3mm nozzles printing ABS? I started with the aim of reaching 120mm/s but after some hours of finetuning I am currently trying to breach the 200mm/s barrier. As I am only using a very old Mendel Prusa I am actually quite happy that I got that far. What speeds are possible with the current printer models? (not the statements on the website, real life)

Topic by Downunder35m 


How do I control this motor? (speed)?

I have a motor 110v 1/3 hp hz 60 phase 1rpm 1750  class B is posible

Question by 3strada1965   |  last reply


How can I reduce the speed of a sewing machine?

Is there an easy way to reduce the speed of a sewing machine?  I'm teaching a young girl to sew, and every machine just goes too fast.   I don't have room for a traditional treadle, but something foot driven would be great.  I need something easy, compact and portable.  At least one machine has an external motor = an external belt.  Any ideas?

Question by mole1   |  last reply


Low Cost DC motor Controler?

I want to power a 90 Volt, 5amp Perment Brush type DC Gear Motor. The, "Variable speed controller", needs to be able to use 115v AC or 115v DC input power, which is selectable by the operator. I have used a Staco variable tranformer which uses 115v AC input and rectified the output to drive the motor. But also need the 115v DC input option.

Question by Realdann   |  last reply


How to make a fast speed clock?

I'm trying to make a clock which its hands move fast, as fast as around 30rpm. Preferably it will cycle like a regular clock, just sped up. Should I attach a motor to the set hand dial on the back? The motor I have at the moment is a DC motor 12v 36rpm except it is really noisy and it needs to be powered by batteries, and I don't think it will last for the length of time I need it to, around 2-3 hours of continuous rotation.  How do I attach it so the motor controls the dial? Do I need to use gears? I'm after the simplest, most efficient solution, please help me!

Question by theclash77   |  last reply


British Land Speed Recod Was a Breeze, Thrashes US Record.

On the morning of March 26th, on the dry Lake Ivanpah, The Ecotricity Greenbird driven by British engineer, Richard Jenkins smashed the world land speed record for wind powered vehicles. The Greenbird clocked 126.1 mph (202.9 km/h) , eclipsing the old, American held, record of 116 mph , set by Bob Schumacher in the Iron Duck in March 1999 at the same location.The fully-composite craft (the only metal is in some of the bearings) used a solid wing to reach speeds up to five times that of the actual wind.The wing also provides unwanted lift, so it uses the same downthrust technology as F1 cars - at speed, the 600kg car presses down on the salt-flats with a force of almost 10,000N.Greenbird website.

Topic by Kiteman   |  last reply


rebuilding a Shimano 7 speed shifter?

I have  a hard rock bicycle with a Shimano 7 speed rear axle and a Shimano three speed front sprocket.  Neither shifter will work.  Is there a way to fix these?

Question by jay oliver   |  last reply


single speed scooter throttle conversion?

I have a scooter controller that requires a three wire throttle. could i just splice two of the three wires together to make it a single speed? the three wires are labled as: voltage ground speed adjusting signal

Topic by budsiskos   |  last reply


1000mph car to be powered by rubber and hair-dye.

The largest rocket fired in the UK for two decades will be lit soon, in the race to produce a land-vehicle capable of 1000mph. It will burn a mixture of solid propellant (HTPB, or hydroxyl-terminated polybutadiene, a kind of rubber) and liquid oxidiser (high-test peroxide, HTP, a highly concentrated form of hair-bleach) for 20 seconds. The Bloodhound SSC will also be powered by a jet engine from a Typhoon fighter. In the 20 second burn, the rocket will need fed with a tonne of HTP, so the pump is being powered by a Cosworth Formula 1 engine, which will become the only piston-engine running in a car at supersonic speed.  The team are planning to give the engine a major power-boost by feeding the supersonic airstream into the engine without slowing it to the usual operating speeds. The huge engineering challenges are being used to inspire students through the UK's STEM programme.

Topic by Kiteman   |  last reply


lawn mower uses. Help

How can I make a lawnmower engine power something like a go-kart for under $20? I don't have a welder but I'm good with tools.

Question by jimmerforpoy   |  last reply


Wacky Races - for real! (where I was Thursday)

I got up early, spent a long time traveling, and fried in the sun to see a whole load of cars (at Goodwood). Here are some pictures. (They're all built around car-chassis and run) L

Topic by lemonie   |  last reply


Salt Attack Project

Dan Holmes pictured on the extreme right is busy with his 2008 Grassroots Bonneville Attack and I wish him well in this endeavor seeing as I'm a Bullet rider myself.Quote from the site Bonneville Bullet "Got motorcycling friends? Motorcycle club, group? Let them know about this underdog, grassroots Bonneville attack by a classic Royal Enfield Bullet and a few dedicated volunteers. We need support from motorcycle owners, riders, enthusiast, groups, clubs, weirdo's, and just plain bike nuts wherever you are."The Bonneville Speed Trials are from 2nd - 7th Sept so not much longer to wait and see history happen. :)

Topic by petercd   |  last reply


Overpriced Stuff: Electric Motor Speed Controllers

Commercially, speed controllers for electric motors (electric car size) are very expensive, like on here.That page has a controller capable of 144v at 550a peak (about 90 horsepower peak) for $1250. I just designed a speed controller with parts off of digikey.com for about $200 that could handle 144v at 690a continuous so it could probably get over 180 horsepower peak.All things considered, their's costs over 10 times as much per amount of power.This seems like a BIG markup. I can understand shipping costs, labor costs, etcetera, but something seems a little messed up here.NOTEI am not sure that the design is quite right, and haven't done it myself, so criticism is good.

Topic by yourcat   |  last reply


can you control an AC motor's speed? Answered

I have a <1hp motor that i'm currently trying to turn into a homemade chopsaw. one of the problems i'm running into is that the motor is spinning too fast for the blade to handle. The idea is that i would use a triac with the gate connected inline with a capacitor that was connected off of one of the ac mains line. the hope was that i could control how much of the waveform the triac chopped off by setting the capacitance of the capacitor to some level where about 3/4 of the way through the cycle it would stop triggering the triac cutting off the end of the wave. is this a possible method of managing the speed of an ac motor or am i setting myself up for heartache and pain in the form of a dead motor? UPDATE: i underestimated the max speed that the chop saw blades are capable of, there's a large enough margin of safety that i'm not worried about overspeeding at all, i will leave this question up because it was answered so concisely and maybe it will help someone else out on their journey. look forward to the chopsaw instructable!

Question by waldosan   |  last reply


device that applies braking force proportional to speed?

Hi, I'm helping a team of students make a brake-assist device for a two-wheeled walker.  We were wondering if there are mechanical brakes out there that apply a force proportional to the speed.  A circular damper, is how we would describe it, I think.  Or something like a gas shock (the things on screen doors and car trunks) but with a circular motion rather than a linear stroke.  Anyone have any ideas?  Anything that's commercially available, small, and somewhat inexpensive is fair game.  Bonus points for things that can be made by hand..  Thanks!

Topic by _mattb   |  last reply


Rewinding a DC motor for different voltages

I modified small DC motors, like used in toys and such but now I have one that requires to do it properly.Motor in question runs on 24V and uses about 3.5A under full load.Drives a high pressure water pump on either side of the shaft.The rotor is basically empty with just a few turns of wire and lots of empty space.I assume the same model is used for multiple power configurations by the manufacturer.For the toys my basic approach was to just calculated the number of turns or to count them when removing.From there I get the voltage per turn and can rewind accordingly.So in theory and by blissfully ignoring all higher things involved I could do this motor the same way.Right now I see 10 windings per coil, so with thicker wire I would use 5 to run it on 12V at roughly the same speed.Only problem is that thing then would use around 7.5 to 8A when running under full load and get quite hot.I need the speed to keep the flowrate at the same 7.5L per minute but I also need the power to be able to still get the 120PSI from just 12V.Isn't there any winding trickery that would allow me to reduce the required current a bit without sacrificing on speed or torque?

Topic by Downunder35m   |  last reply


Would different angles on blades of propeller reduce Speed? Answered

The goal is to reduce speed of my Egg drop contraption but still spinning to keep it accurate.? Basicly its this. 8 blades on a octagon frame then String and then my shock absorbing egg carrier. What way would I want to set my Blades so that it doesn't speed through the air?

Question by noobiefied   |  last reply


Building a sensor chronograph to measure speed of batted ball

I need a sensor chronograph designed to measure the speed of a batted baseball. It would consist of a frame assembly mounted on a pole in front of home plate in a batting cage. The goal would be for the device to be stationary, able to measure the speed of a batted ball on demand and then displaying it on an LCD positioned 30-60 feet away. It should be automatic and unattended, working without anyone doing anything to activate it other than hitting an oncoming pitch. We are interested in measuring only the batted ball, not the pitched ball from the pitcher or the swing speed of the bat. The measuring area would need to be about 2-6 feet high (depending on how far in front of home plate it is positioned) to accommodate a batted ball that is hit high or low. It should be able to measure the speed of any ball hit fair, from the first base line to the third base line.  The speed of the batted ball would range anywhere from 40 to 130 mph. Since the device would be used on a repetitive, long term basis care would need to be taken during the design to provide for protection from any batted balls that might find their way into the device itself (a piece of screen, chain link or plexiglass installed in front of it?) If you know where I might obtain a working apparatus or might locate someone willing to build one I would appreciate your response to the email address below. Jerry Heath jerry@webcitycybercafe.com

Topic by jerryeheath 


How could I build a replacement speed controller for a Zap Zappy Turbo electric scooter. Answered

I found this scooter on the street and picked it up.  I found out that the speed controller was broken and needed to be replaced.  I tried to find one online but nobody is selling one.  I would like to know how to make one or another speed controller that could be used as a replacement. 

Question by hockeymikey   |  last reply


can i use 1 speed controller (24v 350w) for x2 24v 350w motors????its for a electric cart?

Im looking to build a electric cart with two 24v 350w motors but im wondering if i can use just one speed controller for it, the speed controller is 24v 350w thanks james 

Topic by jbutcher05   |  last reply


Motor Speed Controller. I have recently purchased a 115v Bodine Electric 42R Series AC Induction Motor

 I want to be able to control the speed of this motor to use for my homemade brass reloading tumbler. I am currently using a cordless drill which is not practical for the lenght of time the brass must tumble. http://www.youtube.com/watch?v=cvunTv-5x7A The specs for the motor are as follows.. 42R Series AC Induction Motor Standard Features Totally enclosed IP-20 rating. Fan cooled for high output power. Class "B" insulation system operated within Class "A" limits to prolong winding and lubricant life. Aluminum center ring and end shields for high thermal efficiency and light weight. Permanently lubricated, noise tested ball bearings. Locked bearing design minimizes shaft endplay. Application Information Capacitor is not included. Order with motor if required. Models are available with either NEMA C face mount or base mount. Any suggestions would be greatly appreciated.

Question by ehays   |  last reply


Whats the best way to make an air powered go kart? Answered

I have an old go kart I'm fixing up and decided I want to make it run on compressed air. My question is whats the best way to achieve this? I've been debating between having an air motor drive the wheels directly, or having the air motor turn an alternator/generator to power an electric motor. I figured having the compressed air doing the work would require more torque, and therefor more air, whereas if the air motor just had to turn an alternator/generator it would need less torque and more speed. Any help would be greatly appreciated!

Question by thealeks   |  last reply



Does anyone have tried to use a bicycle transmission for a multi-speed mechoui ?

I have an AC motor at 4RPM and I do not want to change the sprockets manually each time to change the speed. I would like to have a mechoui (bbq) which allows to have the following speeds: 4, 6, and 8 RPM. I think modifying a transmission of a bicycle: to change the speed I would just have to actuate the handle. What do you think ?

Question by OlivierM4   |  last reply


dremel 395 type 5 variable speed, change obsolete red switch for newer blue switch ??

My dremel multipro 395 might have a bad obsolete on-off switch, its red with 5 speeds, can i use the newer blue switch   witch is dremel part # 2610912780 ?  thanks.

Question by myoldcar3   |  last reply


Electric Hub Motor

I have 48V 6AH Battery and 350W Hub Motor with controller for Fat tyre CycleIm getting a speed of 40.Hence want to know to increase speed upto 55 or 60

Question by DattatrayaM   |  last reply


bad switch on dremel multipro 395 type 5 variable speed

Im told the switch for the tool is obsolete, there isnt a serial # on the warning lable or any where else on tool only these #'s pa6-gf33, lr5947 and near cord in circles 7  6  8. i dont know witch switch to use. thanks for any help!.

Question by myoldcar3   |  last reply


How do I wire a speed control with a a blinker using 110v indicator lights ?

I have 15 110v  red indicator lights and need to light these one at a time using a speed control  and blinker control to simulate a heart beat. This monitor is the same that you can see in the Classic Monster Movie ,"The Bride of Frankenstein". Any help would be appreciated very much.?

Question by 1stcontact   |  last reply


How does one ensure the feed speed does not exceed the milling speed of the cutter?

When milling any material, if the speed of the axis drive exceeds the capability of the cutter/stock capability rate, the stock will deform or the cutter will overheat, or the axis will jam. Conversely, if the axis is driven too slow,well, that's too slow!  One more, all of the designs I've perused thus far are utilising phase counting to determine where the cutter is, in other words, there seems to be a lack of tracking feedback. So, how does one ensure a 4" circle is a 4" circle and not a 3.5"x3.75" ellipse?

Question by burnerjack01   |  last reply



LSHV FAN

Has anyone attempted to make a large Low Speed High Velocity Warehouse Ceiling Fan?

Topic by darrinbaker   |  last reply


I am looking for a rotating carousel or display, battery operated, variable speed.

I have started paining glassware.  I have an "artist's turnstyle" that has clamps to hold the glasses in place.  The base turns, but manually turning it leaves a lot to be desired in the quality area.  I thought about taking a Lazy Susan, adding rubber to the outer edge, and then place the Lazy Susan next to the turnstyle.  I could continuously spin the Lazy Susan which would in turn turn the turnstyle.  That might work for one or two glasses, but too many of them would cause callouses on my fingers, and the speed would vary.  My son suggested his K'nex motor and make a motorized small wheel to mount next to the carousel.  Sounds good, but does not have variable speed.      My husband wants to take a small motor and control the speed  with a foot pedal.  That would require me to concentrate on the speed, not necessarily the painting.  So I turn to the gadget makers for some suggestions or instructables.     

Question by keglermom   |  last reply


anyone there

Is this gruopstill alive i loved speed challenges they were so much fun

Topic by Dowaine   |  last reply


looking for a component to control my 36v500w motor speed and direction from an arduino

Hello! I am currently trying to build my won electric scooter. i bought this motor http://www.ebay.com/itm/Razor-MX500-Dirt-Rocket-Bike-Electric-Scooter-Motor-36V-500W-MY1020-P-ST20-/141293042627?pt=Motors_ATV_Parts_Accessories&hash;=item20e5b8bbc3&vxp;=mtr and i have a 38v 10A battery which i plan on turning into 20A further more i plan on using a resistor to change the out volt to 36v. i am now looking for a controller that i can connect to an arduino so the arduino can control the speed and direction of the motor. any suggestions?

Question by bfeher1   |  last reply


What is the best way to remove rust from chrome on an old bicycle. I have a vintage schwinn I'm restoring on the cheap?

This is a 70's or 80's schwinn ten speed I'm converting into a single speed road bike. The paint is still good, the frame is in good shape. But there is rust on the crank, handlebars and other area's. 

Question by upnorth777   |  last reply


How can I set up a dental tool as a high speed hobby engraver? Answered

I have this:  http://www.dickblick.com/products/iwata-sprint-jet-studio-compressor/#itemspecs  Compressor and I know it can't run it with something like this:  http://www.treelineusa.com/power-carving/pneumatic-tools/nks-presto-handpiece.html or can I? What I don't know is can it run a dental tool. Something like this:  http://www.ebay.com/itm/Portable-Dental-Air-Turbine-Unit-4-Holes-2-High-Speed-Push-Button-Handpiece-/251980511734?pt=LH_DefaultDomain_0&hash;=item3aab3579f6 Though that thing says / w compressor... I don't think that thing is a compressor.  Can anyone shed some light on this for me? I would love to be able to carve into wood or eggs or do calligraphy with one of these tools

Question by drapeta   |  last reply


acrlic de-buring bit to use with dremel 395 type 5 variable speed.?

I want to de-bure and shape some old dentures,witch bit do i use? dremel nas alot of different corored grinding bits. thanks.

Question by myoldcar3   |  last reply


A good way to add a variable speed controller for my re-made Hobbies fretsaw.

Hi folks. I have decided I want to add a variable speed foot controller to my re-made hobbies fretsaw. https://www.instructables.com/id/1950s-Hobbies-treadle-fretsaw-remade/ My question is what do you guys out there think would be the easiest, least costly (cheap) way of doing it? I have given some thought to using a foot controller from a sewing machine possibly because this thing started life as a treadle fret saw & I guess it seems fitting that it should follow a similar evolution as sewing machines did. I know very little about sewing machines so if anyone has any ideas regarding this I would welcome them. I plan to include an isolator switch on the machine itself, it seems a good idea as we have a small grandson who visits very often as well as two dogs & 'ible the kitten & as much as I try to keep them out of my tiny workshop it sometimes seems as if I am the only person in the house who has mastered the skill of closing the door so with all those feet around I want to be able to kill the power when I am not actually cutting. So there you go guys what does the combined genius of the 'ibling world have to suggest for my little project?

Question by Nostalgic Guy   |  last reply


Deriving the maximum range and angle of a projectile

In a thread in the Green group, AnarchistAsian and I were discussing his coil guns. I posed the question of what range he could get, and he asked me to go through the physics derivation. Here it is, simplified to require just algebra and trig.The kinetic energy of the projectile E = ½mv2, gives v = sqrt(2E/m) as the speed at launch. Let θ be the angle at which you launch (θ=0° is horizontal, θ=90° is straight up). Then you can decompose the speed into two components: vh = v cos(θ) is the horizontal speed,vv = v sin(θ) is the vertical speed.Gravity only pulls vertically, so the projectile's vertical speed will be slowed down until it reaches its maximum altitude, then it will fall back until it hits the ground. The horizontal speed will remain constant until it hits the ground and stops. To figure out the range, you need to know the time t that the projectile flies before it hits the ground; then the range is just R = vhtEnergy conservation guarantees that it's downward speed at the end is equal to its original upward speed, just with a change of sign. That also means that the total flight time of the projectile will be half going up and half going down. Once you determine how long it takes to reach the top of its flight, you're done; just double that answer :-)In the vertical direction, the maximum heightH = vvt - ½gt2(you need calculus to derive this result). From energy conservation, the initial kinetic energy in the vertical direction, Ev = ½mvv2 must equal the potential energy at the top of the flight, Pv = mgH:mgH = ½mvv2H = ½vv2/gSubstitute this on the left hand side of the trajectory expression,½vv2/g = vvt - ½gt2vv2 = 2gvvt - g2t2vv2 - 2gvvt + g2t2 = 0(vv - gt)2 = 0vv = gtSo, t = vv/g = v sin(θ)/g is the time to reach maximum height. Double that as discussed above, and you get the range R = 2 sin(θ) cos(θ) v/g.Work out the angle that gets you maximum range by just plugging in different angle values and finding the one that is biggest.

Topic by kelseymh   |  last reply



electric micro kart

I want to build a micro kart with a range of 10 miles at an average speed of about 5mph, with a reverse function. Iv been looking at blogs and Instructables for micro karts and DIY electric longboards hoping to directly copy the basic components of another project however all the projects iv found are for high speed machines that often need a bump/kick start and i need something that will happily run at consistently low speeds without an assisted start. I don't have the electronics knowhow to work out what combination of motor, battery and ESC i need but from what iv read it sounds like i might need an outrunner (?) type motor which is apparently good for low speeds and high torque. Iv been looking at the Turnigy motors on the Hobbyking website as they were recommended by a few blogs, i tried posting this question on their forums a week ago but got zero response. Could you take a look at their motor selection and recommend the appropriate combination of parts? Thanks

Topic by ambientvoid   |  last reply


How do i wire up a brand new 2.5hp treadmill motor & speed controller ?

Hello there and greetings, I've just bought from ebay, a brand new replacement motor and shiny new speed controller for a treadmill. The motor is a PM DC cont. duty, 2.5hp @ 230VDC, 9.5Amps.  It has 4 wires coming out of it, Red, Black (connected to the brushes on the motor), and two blue&white; wires which are connected together using spade connectors. The speed controller board is fiited inside an aluminium heat sink case.  It has 7 male spade connectors protruding and they are labelled: LG1: Blue..........(AC1) LG2: White........(AC2) LG3: ..................(Earth Ground) CHOKE: LG4 LG5 AC MOTOR: LG6: Red..........(A+) LG7: Black........(A-) I'm afraid i don't possess the know-how although i'm quite handy and have some faded kowledge of electrics and electronics but i'm afraid im not too sure how to hook it up. Also could someone tell me what kind of power supply i need for this setup. Much appreciated and many thanks in advance.

Question by jackherer   |  last reply


Alternator to generate power?

If got an old car alternator and want to connect it to a battery, I'm using a waterfall to turn a bicycle weel with blades, to turn the alternator. is the slow speed going to be a problem?

Question by HermannR6   |  last reply


How can I use this router bit? Answered

I recently purchased a big 2 HP router and a 15 bit set from Harbor Freight. The router is going on the finished CNC router, but I also needed it to make a few chamfers on the sides of some of the parts. The router is one speed, and says that it has a "Maximum RPM of 29000". The chamfer bit that came with the set, on the other hand, says that it has a max speed of 18000. What do I do, now?

Question by Shagglepuff   |  last reply


How can I select a suitable bldc motor?

We are designing an electric tricycle having rear wheel drive(26 inches wheel dia).It will weigh around 400kgs including drivers. There are constraints for motor output power(max 400 watts) and voltage(max 48v). What are the calculations to be done for the selection of motor. The desired speed of the vehicle is 0 to 4m/s in 20 seconds. How can I calculate the speed of the vehicle for hill climbing(max 7degree gradient)?

Question by shravana2   |  last reply


Solar panel mounting and tracking.

I have a new video about equatorial mount for solar panels. If equatorial mount is turned slowly at the right constant speed, then the panels point at the sun all the time. I also have a diagram about something to get that constant slow speed. I have it done this way to avoid wind damage. I think if you did it this way and had a sump pump to pump the water back up every morning the thing could be  automatic, cheap  and very accurate. Brian

Topic by gaiatechnician   |  last reply


can i use motor to run the small generator instead of fuel engine?

I want to know which card i will use to control the voltage and frequency and speed.

Question by geminiyasir   |  last reply


whats the most indestructible metal?

As in indestructible I mean indestructible to impact, like it can stop a speeding bullet and it wont make a dent, and it's strong enough to block a jack hammer, basically very strong.

Question by ha_neenn   |  last reply