As others have pointed out, you need to measure voltage and current at the same time. Also, when measuring current, your multimeter is set to mA, but your leads are connected to the unfused 10A sockets. This will give unreliable results.
Yep, the more amperage drawn, the most the voltage will drop. And the more connection the more resistance would be present is true also, thus unreliable results.
Yeap. But we need to recognize that the results are pretty accurate. You are absolutely right about the error, but it's just not that negligible when we're up to huge machines.
That’s the chines way for any Produkt they advertise 😂 But you right he needs an powermeter or he should measure the voltage over nen given resistance.
@@Comfy_Bed Well in the video he also mentioned that he couldn't spin the motor as fast as he could when he connected the leads. So it would be best if he connected some wire with known resistance or use a low value resistor and measure the voltage drop through the resistor then use P=V^2/R formula.
I agree. You need to consider that when the supply is loaded, the voltage drops. You need to calculate the dropped voltage by the amps being drawn to figure out the real wattage. Most generators have a 'sweet spot' where they're most efficient too. ie, if you over-load the generator and pull too much current, the voltage will drop significantly. Since the power is voltage * amps, it actually reduces the power delivering capacity. So let's say you could pull up to 2A before the voltage drop starts to happen. If we're generating 10V and pulling 500mA, we have 10V * 0.5A = 5W of power. But we could draw 1.9A and get 1.9A * 10V = 19W of power. Now we'll draw 3A which drops the voltage down to about 2.5V... 2.5V * 3A = 7.5W of power. Most modern phone battery charging circuits take advantage of this to charge the battery as quickly as possible with any power supply - They'll ramp up the current until they detect voltage drop. At which point they'll knock back the current draw by a fraction. This gives the hightest current available for the 5V supply over USB.
Great video! But unfortunately as others have pointed out, you didn't measure power correctly. It doesn't look like anyone has explained how you should really do it, so try this: You should buy a power resistor. A 100 Ω resistor rated for 25 W would work fine and only costs like $5. BTW power resistors can also greatly exceed their power ratings for short periods of time, so it's fine if you produce over 25 W. Once you have it, connect it to the output leads of the generator, and hook up your multimeter to measure the voltage across it, and do some simple math. If you have a 100 Ω resistor and see 12 V across it, then you know your current because 12 V ÷ 100 Ω = 0.12 A. You'll also know how much power you're generating because 12 V × 0.12 A = 1.44 W. Good luck to you! PS. I don't know if you'd be interested, but I have a bunch of experience in 3D printing entire electric motors and have dabbled into 3D printing magnetic gearboxes. It might be cool to collaborate on something.
Yep. Knew measuring voltage and current separately was not the correct idea. My question is, would it be correct to measure power by using two multimeters at the same time? One for current and one for voltage?
Getting the gearboxes to spin faster: mounting them with bolts/screws would be a great idea so you didn't have to hold them down for the spinning. This may look like a heavier-duty more industrial stand than what you've been printing, but that way, you could both get a faster and more consistent turn of the crank. And, speaking of the crank, if you increased the distance between the crank shaft and crank handle, you'll have significantly increased leverage, and thus an easier time to spin quickly and consistently. Seeing a metal gearbox would be fascinating. It would be a great way to compare the friction outputs of similar gearboxes with different materials; not to mention spin speed and electrical output differences.
Nice work on the gears, looks like you've stepped things up a lot in how you've designed/put these gears together. Question though: You're measuring the voltage without load, and the current is being measured with the meter acting as a dead short.
He is using permanent magnet DC motors as generators, therefore the output will be DC. But yeah, voltage and current must be measured at the same time.
3:27 if you are wondering why he doesn't just hold its handle. it's because for some reason when it's connected to something it's meant to power it becomes extremely difficult to move and feels almost impossible to get a good grip on
@@_vizec almost. The reason is the DMM uses a shunt resistor, and the current goes through it, so it's essentially short-circuits the generator, thus it draws all available power. This creates opposing magnetic fields making it difficult to spin.
You need to do comparisons on a standard load not just the open load voltages or currents. Although its ok for simple scenarios. You can also start with the law of conservation of energy or just the fact that if gear ratios increase or decrease speed, they do the inverse for torque.
On that high speed gearbox, you need a bushing on the crank handle hole. This will spread out the forces, prevent enlarging of the hole itself, and make for a more secure crank handle. A bushing and bearing would work even better, but as we see in the video, even trying to use that crank for only a short bit wallowed out the hole it was in.
A fun little test. and thanks for that, I really like your videos. But it just does not quite work out in reality. You will need to measure the energy you are getting into the system at the same time to get an idea of the output. And you can not measure voltage and amp separately, it must be done simultaneously with 2 multimeters. In the test you use 2 different generators, it will certainly also give different results. Suggestion: how about setting a motor to drive the input shaft, use the same generator at different gears, measure amp and voltage simultaneously.
As someone who rebuilds industrial DC generators for steel mill conditions, I can tell you that most of the MG sets run at 1200-1800 rpm but I have seen some slower. They have a synchronous motor (an AC stator with a DC rotating field element that maintains a consistent speed without slippage) coupled to several (separately excited or series excited) DC generators on both ends of the motor. There is a direct mathematical relation of work done in HP to the output voltage and supplied possible amperage output. Horsepower = Torque x RPM / 5,252 and 1 HP = 745.7 Watts. Knowing this, you can deduce that the rpm can vary but what really leads to a higher output is the torque in the system. You can build a DC generator to maintain a certain EMF at variable rpm by adjusting of your excitation field in response (the bread and butter of series excited generators) but the actual amp(flow) output under load leans more on the torque of your driving force. AC generators are a completely different beast and are more dependent on RPM over torque with the speed being the deciding factor in the output frequency. Most run at 3600+ rpm with 3600 being more common in the United States in order to make that 60Hz frequency.
That makes sense from a mechanical perspective as well. If you're riding a road bike, you can pedal the smaller gear ratio a lot faster to pick up speed and get going, and the big gear ratio, while requiring much more force, outputs a lot more power.
2:05 You are using your multimeter in 2mA range, so you arent getting 200mA from that motor, you are getting less than 1mA (0.234mA), and 2:43 you set it into 20mA range, so from that bigger motor you are getting 2-3mA - barerly to light up an LED, you can connect LED and see how much power you are really generating. For generating power purposes you should always use brushless DC motors, because they use permament magnets
Multiplying Voltage with nothing else connected by short-circuit current does not yield achievable output power. You will have to attach a decent load resistor and measure Voltage AND power under that load. What constitutes a decent load depends on the specifics of the generator. If you don't have those specifics, measure it's resistance while it is stationary and use that value for the load resistor.
I was looking at this as a means to make a gravity "battery" more efficient, as in needing the weight to fall more slowly, thus decreasing the distance it has to fall. Over a certain weight, the torque would be irrelevant, for all practical purposes. A flywheel might help even further, though it might not be necessary.
generators have a perfect speed at which they have the highest productivity, but the input energy also matters - the harder you crank the handle the more power you put in, but lots of gears invite a lot of friction, which is power lost. Makes sense a bigger generator will be more productive. When you hooked up to measure current, the multimeter became a load, and that resistance of the generator was the effectiveness of converting input energy to current. The small one didnt give much resistance, which means its not an effective generator.
Somthing that would probably help you is getting a solid surface you can turn better plus use triangles to help with the turnes and make the gears closer together
seems like, for this to be a fair comparison, you'd have to use the same alternator for both setups. different sized alternators will have different efficiencies.
What if you designed a small custom motor that is specifically designed for the small and fast gear setup? You did mention the coils and magnets play a big role in current generation so perhaps making an hybrid motor will improve the output?
What would happen if you were able to drop a weight from a height as input to drive the crank? Already out of my wheelhouse ...would adding a capacitor after generator help to reduce the start force needed?
the speed to power generation potential of your gearbox will directly correlate to what kind of induction motor your using, if your using a high RPM low torque motor then high speed will work better but if your using a low RPM high torque motor the opposite will apply, that's why they use high torque for water turbines and low torque for wind turbines
Better bearings would greatly narrow the margin between high speed low torque, Vs. Low speed, high torque. The gears themselves, look really good. If they spun on precision ball bearings, that would reduce the losses of going through that many stages. I would start with a good crank bearing, since that's the one that takes the most severe radial load. making the axle longer, to put space between the bearings, will make them more stable against the cantilever loading caused by turning the crank by hand.
I'd be interested to see you use a higher gear ratio for more spins, attach the bigger motor, extend the handle way out at about 75°, then add a heavy weight at the end. The handle will only turn roughly a quarter but the spins a power generated should be high.
Well, you need to connect a voltmeter and a currentmeter together since the open circuit voltage and the loaded voltages are diffetent. And also when the probe is in the 10A range, switch the meter to 10A range.
Instead of a hand crank could a heavy weight on line that unravels as it falls (slowly due to the resistanceof the gear ratio), maybe the height of the room for prolonged duration?
Does it matter which direction the generator is turned? If it was turned in one direction for an hour & then the other direction for an hour, is there are generator that would work in both directions?
Could an unwinding spring be used to automate the crank for some time? A big, strong spring like the ones used in garage door openers? And for that matter, wouldn't increasing the time it takes for the first gear to revolve once (maybe by adding gears to the system then compensating for the added necessary force with a stronger spring?) mean that the spring would take longer to unwind, thus elongating automation? How far could that be taken? How long could an unwinding spring automate the system? If it could. I'm no engineer and I'm sure the nature of my questions reveal my ignorance. But I thought it seemed like a simple enough mechanism with potential.
@@3DPrinterAcademy do you have access to a lathe? Drill out a pinion big enough for bearings to go inside, drill out a spur with an interference fit with the hub of the pinion, press fit (or thermal press fit) them together.
I imagine that you could run quite a few small generators on that setup though. I'm curious how many you could fit and what those numbers would look like.
2:50 "When you're measuring current [amps], there's a lot of resistance in the motor." I've been using a multimeter my whole long life, but I don't remember ever reading this in the instructions. In fact, Googling text instructions about this produced nothing. It was only when I looked for video instructions on how to measure generator current that anyone mentioned this. Learn something new every day! 🤔
Power output, in wattage, versus power input, will give you the efficiency. Nothing else matters. And that wasn't measured in any meaningful way. I have a generator that will put out 50 kilovolts.
@@3DPrinterAcademy It doesn't, you didn't measure input power therefore efficiency calculation is impossible. Ignoring the obvious issue with your output power measurements.
3:45 , you forgot to speak about the Energy efficiency of the motors ^^ It make a significative difference. Biggest generators have better efficiency. The type of motor winding and there characteristics are also a part of the equation. . . But i understand that you want to keep it more simple
On top of what others have pointed out, have you made sure you're inputting the same amount of wattage into each system? Sure, the small one produced less, but how do you know this isn't just because you were inputting less energy?
there's a problem in your calculating . When you measure the voltege across the motor , the internal impedence's motor is zero. Because it's like an open circuit (the impedence of a multimeter has to be very high, in this way the current flow is almost zero). So you can get an accurate voltage's value. But when you connect the motor to the tester, for measure the current, in this case the impedance of a tester is almost zero, so the motor sees two impedances, that of tester and internal motor. You have so a drop voltage that you're not considering.
Any generator will provide more electricity if driven at a higher speed but there will be an optimal speed above which the output will begin to fall as mechanical and electrical losses increase. The losses will appear as heat.
The short answer is yes, unless it has a voltage regulator on it. Because otherwise a alternator would create more voltage as rpms increase, but it doesn't create more than 14.?? Volts at any given time.
what if you connect the small motor into the place where the handle of the big generator is and power the small motor with the current produced by the big generator
As a control I think he should be using the same generators for both gear ratios. Metal and nice bearings will help so he can crank of them as hard as he wants
Can you like make gear box like this which like makes the last gear spin soo fast that in a hour atleast you can power up your whole house for 10 minutes, it would be such a energy saver
Seems counter intuitive because I thought the equations would be related to KE = 1/2 mv^2. The fast gear spins 15 times faster than the slow one. 15 ^2 is 225 so I expected the fast gear would create more power. I thought all energy variables (kinetic, potential, electrical) were interchangeable such as watts and joules.
Conservation of energy works everywhere. Did you account for the mass that is being rotated in both accounts? And also the efficiency of the motors to convert mechanical energy into electrical energy?
Hi, sorry to be THAT guy, but to messure watts, you need to measure volts and amps at the same time. Because, when you load a power source, the voltage usually drops from an open circuit.
Its interesting, in general we could describe de open load voltage of a CC machine in terms of speed and exciting magnetic flux, for permanent magnets we could say that the magnetix flux is going to be constant, so your open load voltage is going to be speed dependent only. Besides that the amount of mechanical power you inject in a system is equal to torque times rotational speed en rad/s. You have to consider that the amount of mechanical power wasn't exactly the same for both cases. Whatever it was a nice experiment though :) .
But if you tweaked the fast rpm generator to have a little more torque and less speed couldn’t you use the large generator with the faster rpm? Or am I missing something mathematically
All direct contact 1 gear to motor must spin a dc motor up to at least 1800Rpm up to 2500rpm for the ebike 250w motor show. So unfortunatelly, you didn't have a proper test in this video. You should use heavy duty gears with 1:50 RPM ratio. EVERY 30 TURNS FROM YOUR HAND WILL PUT OUT 1500Rpm to the motor. Try to design helical gears instead of spur gears. And use three phase ac motors for your diy project. Dc brushed motor generate sparks that will damage your brushes in a short time if you use a brush dc motor as a generator. This is why wind turbines are three phase ac motors, no brushes reguired. I know you are good guy. And I understand that you could not afford heavy expensive gears. That's ok. Anyway, nice to see your little diy.
![Seungmin "그렇게, 천천히, 우리(As we are)" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/kAzmhLHePqU/mqdefault.jpg)
This man sure does love his 3D-printed gearboxes
He should make metal ones and put them to torque test
@GlueEater87 people who don’t
@GlueEater87 neither here lol
yeah, just start up a company and partner up with another company who makes valves
More gear boxes
As others have pointed out, you need to measure voltage and current at the same time. Also, when measuring current, your multimeter is set to mA, but your leads are connected to the unfused 10A sockets. This will give unreliable results.
Yep, the more amperage drawn, the most the voltage will drop. And the more connection the more resistance would be present is true also, thus unreliable results.
Yeap. But we need to recognize that the results are pretty accurate. You are absolutely right about the error, but it's just not that negligible when we're up to huge machines.
Yeah you need to plot resistance against voltage to actually get any sort of idea as to what power it produces
0:17 its funny when the big one spawns
BUENAS TARDES DONDE PUEDO CONSEGUIRLO COMPLETO COMO ESTA EN EL VIDEO
You need to measure current and voltage at the same time, NOT measure unloaded voltage and then multiply by the short circuit current.
That’s the chines way for any Produkt they advertise 😂
But you right he needs an powermeter or he should measure the voltage over nen given resistance.
would it give massively different results?
@@Comfy_Bed Well in the video he also mentioned that he couldn't spin the motor as fast as he could when he connected the leads. So it would be best if he connected some wire with known resistance or use a low value resistor and measure the voltage drop through the resistor then use P=V^2/R formula.
I agree.
You need to consider that when the supply is loaded, the voltage drops. You need to calculate the dropped voltage by the amps being drawn to figure out the real wattage.
Most generators have a 'sweet spot' where they're most efficient too.
ie, if you over-load the generator and pull too much current, the voltage will drop significantly. Since the power is voltage * amps, it actually reduces the power delivering capacity.
So let's say you could pull up to 2A before the voltage drop starts to happen.
If we're generating 10V and pulling 500mA, we have 10V * 0.5A = 5W of power.
But we could draw 1.9A and get 1.9A * 10V = 19W of power.
Now we'll draw 3A which drops the voltage down to about 2.5V... 2.5V * 3A = 7.5W of power.
Most modern phone battery charging circuits take advantage of this to charge the battery as quickly as possible with any power supply - They'll ramp up the current until they detect voltage drop. At which point they'll knock back the current draw by a fraction. This gives the hightest current available for the 5V supply over USB.
The test also need to be done on same motors to prove the variable "speed" has any effect
You need a flywheel on the fast gear set to maintain speed and store energy momentum.
For the big generator just get a slight faster speed and wala!
r/BoneAppleTea
voilá!
Great video! But unfortunately as others have pointed out, you didn't measure power correctly. It doesn't look like anyone has explained how you should really do it, so try this:
You should buy a power resistor. A 100 Ω resistor rated for 25 W would work fine and only costs like $5. BTW power resistors can also greatly exceed their power ratings for short periods of time, so it's fine if you produce over 25 W. Once you have it, connect it to the output leads of the generator, and hook up your multimeter to measure the voltage across it, and do some simple math.
If you have a 100 Ω resistor and see 12 V across it, then you know your current because 12 V ÷ 100 Ω = 0.12 A. You'll also know how much power you're generating because 12 V × 0.12 A = 1.44 W.
Good luck to you!
PS. I don't know if you'd be interested, but I have a bunch of experience in 3D printing entire electric motors and have dabbled into 3D printing magnetic gearboxes. It might be cool to collaborate on something.
thanks for the info bro
Yep. Knew measuring voltage and current separately was not the correct idea.
My question is, would it be correct to measure power by using two multimeters at the same time? One for current and one for voltage?
Getting the gearboxes to spin faster: mounting them with bolts/screws would be a great idea so you didn't have to hold them down for the spinning. This may look like a heavier-duty more industrial stand than what you've been printing, but that way, you could both get a faster and more consistent turn of the crank. And, speaking of the crank, if you increased the distance between the crank shaft and crank handle, you'll have significantly increased leverage, and thus an easier time to spin quickly and consistently.
Seeing a metal gearbox would be fascinating. It would be a great way to compare the friction outputs of similar gearboxes with different materials; not to mention spin speed and electrical output differences.
Nice work on the gears, looks like you've stepped things up a lot in how you've designed/put these gears together.
Question though: You're measuring the voltage without load, and the current is being measured with the meter acting as a dead short.
He is using permanent magnet DC motors as generators, therefore the output will be DC.
But yeah, voltage and current must be measured at the same time.
@@IZuzivowoI Cheers, I've updated comment. Not sure what I was thinking
You didn't ask a question
@@DiacnikYT It's implied, i'm questioning their methods because measuring voltage without load, and measuring current as a dead short is meaningless.
3:27
if you are wondering why he doesn't just hold its handle. it's because for some reason when it's connected to something it's meant to power it becomes extremely difficult to move and feels almost impossible to get a good grip on
The “some reason” is Lenz’s law
@@_vizec almost. The reason is the DMM uses a shunt resistor, and the current goes through it, so it's essentially short-circuits the generator, thus it draws all available power. This creates opposing magnetic fields making it difficult to spin.
No. It's about how much power you input into the gear, minus the friction loss, times the efficiency of the generator.
may I know why you still avoid planetary gears for this gear up ratio ?
I was actually thinking about making a planetary gear video soon!
@@3DPrinterAcademy please do.
@@3DPrinterAcademy if you need a hand I can provide the STLS for a planetary… we can work on the ratios together
@@3DPrinterAcademy what generator was the larger one?
As an engineer, im triggered... Nothing about this makes a shred of sense.
You need to do comparisons on a standard load not just the open load voltages or currents. Although its ok for simple scenarios. You can also start with the law of conservation of energy or just the fact that if gear ratios increase or decrease speed, they do the inverse for torque.
On that high speed gearbox, you need a bushing on the crank handle hole. This will spread out the forces, prevent enlarging of the hole itself, and make for a more secure crank handle. A bushing and bearing would work even better, but as we see in the video, even trying to use that crank for only a short bit wallowed out the hole it was in.
Also a larger crank could help with ease of use
A fun little test. and thanks for that, I really like your videos.
But it just does not quite work out in reality.
You will need to measure the energy you are getting into the system at the same time to get an idea of the output.
And you can not measure voltage and amp separately, it must be done simultaneously with 2 multimeters.
In the test you use 2 different generators, it will certainly also give different results.
Suggestion: how about setting a motor to drive the input shaft, use the same generator at different gears, measure amp and voltage simultaneously.
As someone who rebuilds industrial DC generators for steel mill conditions, I can tell you that most of the MG sets run at 1200-1800 rpm but I have seen some slower. They have a synchronous motor (an AC stator with a DC rotating field element that maintains a consistent speed without slippage) coupled to several (separately excited or series excited) DC generators on both ends of the motor. There is a direct mathematical relation of work done in HP to the output voltage and supplied possible amperage output. Horsepower = Torque x RPM / 5,252 and 1 HP = 745.7 Watts. Knowing this, you can deduce that the rpm can vary but what really leads to a higher output is the torque in the system. You can build a DC generator to maintain a certain EMF at variable rpm by adjusting of your excitation field in response (the bread and butter of series excited generators) but the actual amp(flow) output under load leans more on the torque of your driving force. AC generators are a completely different beast and are more dependent on RPM over torque with the speed being the deciding factor in the output frequency. Most run at 3600+ rpm with 3600 being more common in the United States in order to make that 60Hz frequency.
That makes sense from a mechanical perspective as well. If you're riding a road bike, you can pedal the smaller gear ratio a lot faster to pick up speed and get going, and the big gear ratio, while requiring much more force, outputs a lot more power.
2:05 You are using your multimeter in 2mA range, so you arent getting 200mA from that motor, you are getting less than 1mA (0.234mA), and 2:43 you set it into 20mA range, so from that bigger motor you are getting 2-3mA - barerly to light up an LED, you can connect LED and see how much power you are really generating.
For generating power purposes you should always use brushless DC motors, because they use permament magnets
I don't know what u r talking about but I definitely got an impression that the RUclips guy has really messed it up.
You should try covering the gears with magnets and surround it with a lot of copper wire to make your own generator
Multiplying Voltage with nothing else connected by short-circuit current does not yield achievable output power. You will have to attach a decent load resistor and measure Voltage AND power under that load. What constitutes a decent load depends on the specifics of the generator. If you don't have those specifics, measure it's resistance while it is stationary and use that value for the load resistor.
I was looking at this as a means to make a gravity "battery" more efficient, as in needing the weight to fall more slowly, thus decreasing the distance it has to fall. Over a certain weight, the torque would be irrelevant, for all practical purposes. A flywheel might help even further, though it might not be necessary.
Please do the metal one
generators have a perfect speed at which they have the highest productivity, but the input energy also matters - the harder you crank the handle the more power you put in, but lots of gears invite a lot of friction, which is power lost. Makes sense a bigger generator will be more productive. When you hooked up to measure current, the multimeter became a load, and that resistance of the generator was the effectiveness of converting input energy to current. The small one didnt give much resistance, which means its not an effective generator.
Soooo which one can charge my phone?
Insert it directly to the 11KV Transformer 😊😊😊
3:58 love this he already knew all his views have common electrical sense
Do it! Do a metal version of this!
2:22 when you dont use the handle, and create a false reading
Great description! Finally someone addressed the power vs speed principle
Nice work!
Somthing that would probably help you is getting a solid surface you can turn better plus use triangles to help with the turnes and make the gears closer together
seems like, for this to be a fair comparison, you'd have to use the same alternator for both setups. different sized alternators will have different efficiencies.
What if you designed a small custom motor that is specifically designed for the small and fast gear setup? You did mention the coils and magnets play a big role in current generation so perhaps making an hybrid motor will improve the output?
Motors and generators with higher frequenci are generaly smaller than wlow frechency machines with the same power output , so less cost on materials
What would happen if you were able to drop a weight from a height as input to drive the crank? Already out of my wheelhouse ...would adding a capacitor after generator help to reduce the start force needed?
the speed to power generation potential of your gearbox will directly correlate to what kind of induction motor your using, if your using a high RPM low torque motor then high speed will work better but if your using a low RPM high torque motor the opposite will apply, that's why they use high torque for water turbines and low torque for wind turbines
Better bearings would greatly narrow the margin between high speed low torque, Vs. Low speed, high torque. The gears themselves, look really good. If they spun on precision ball bearings, that would reduce the losses of going through that many stages. I would start with a good crank bearing, since that's the one that takes the most severe radial load. making the axle longer, to put space between the bearings, will make them more stable against the cantilever loading caused by turning the crank by hand.
Saving this for the power comparisons, but would still like to see the gear stack work on the large motor
i have been wondering this for ages thank you so much
im gonna subscribe since you did this.
I'd be interested to see you use a higher gear ratio for more spins, attach the bigger motor, extend the handle way out at about 75°, then add a heavy weight at the end. The handle will only turn roughly a quarter but the spins a power generated should be high.
Well, you need to connect a voltmeter and a currentmeter together since the open circuit voltage and the loaded voltages are diffetent. And also when the probe is in the 10A range, switch the meter to 10A range.
So what’s best for charging amps or volts?
It depends, for charging a phone the voltage will have to be 5v (USB standard) and the more current / amps the faster it will charge the device.
@@3DPrinterAcademy didn’t know if the excess volts but less amps would be an issue or not
Please put up where you got the big generator
Instead of a hand crank could a heavy weight on line that unravels as it falls (slowly due to the resistanceof the gear ratio), maybe the height of the room for prolonged duration?
Thanks for this!
Make the gears from metal!! That would be great to see
May i suggest adding small heavy flywheel to start the first momentum and help for the next momentum
Does it matter which direction the generator is turned?
If it was turned in one direction for an hour & then the other direction for an hour, is there are generator that would work in both directions?
I see the handle is very loose on the fast gearbox, making it metal would be a good decision, if you oiled it.
Could an unwinding spring be used to automate the crank for some time? A big, strong spring like the ones used in garage door openers? And for that matter, wouldn't increasing the time it takes for the first gear to revolve once (maybe by adding gears to the system then compensating for the added necessary force with a stronger spring?) mean that the spring would take longer to unwind, thus elongating automation? How far could that be taken? How long could an unwinding spring automate the system? If it could. I'm no engineer and I'm sure the nature of my questions reveal my ignorance. But I thought it seemed like a simple enough mechanism with potential.
You can just buy metal gears from SDP/SI and it would be a lot cheaper than 3D printing them.
I don't see that have compound gears unfortunately
@@3DPrinterAcademy do you have access to a lathe? Drill out a pinion big enough for bearings to go inside, drill out a spur with an interference fit with the hub of the pinion, press fit (or thermal press fit) them together.
I imagine that you could run quite a few small generators on that setup though. I'm curious how many you could fit and what those numbers would look like.
Maybe if he extended the small gear on the last one he could move the large gear out further and put a bunch around the big gear
you can put motor at the input so you can generate big volt on output (generator)?
One flywheel added on motor rotor and make last spike wheel gear with one direction free rotation mechanism will provide greater afficiency
So amazing video and explaining
Sooo…. Hook the big generator to the high ratio gears maybe?
The high gear ratio gearbox doesn't have enough torque to spin the big generator
@@3DPrinterAcademy You can do anything with a long enough lever.
Anyone who knows a bit about friction knows the answer up front. Still a nice Video
2:50 "When you're measuring current [amps], there's a lot of resistance in the motor." I've been using a multimeter my whole long life, but I don't remember ever reading this in the instructions. In fact, Googling text instructions about this produced nothing. It was only when I looked for video instructions on how to measure generator current that anyone mentioned this. Learn something new every day! 🤔
I would like to see a full metal version of the gearbox
Can you explain how to start 3d printing from scrach.
Why are they always limited to a crank to generate energy? what happened to the spring-loaded toys?
i instantly know the big one should be better
if you have the same watts of input
bcs of the resistance on the gears
Yep. More 3d printed gears means more friction and less efficiency.
In theory, yes; theres a major increase of torque required and on top of that quite a bit of energy is lost to friction and entropy.
he says that in the video later on I see
Does this wear down the 3d printed parts? And is this gearbox available to 3d print?
hi, what are your dimensions of the gears? for a science project :) thx
Power output, in wattage, versus power input, will give you the efficiency. Nothing else matters. And that wasn't measured in any meaningful way. I have a generator that will put out 50 kilovolts.
The results show that the gearbox with more gears is considerably less efficient
@@3DPrinterAcademy It doesn't, you didn't measure input power therefore efficiency calculation is impossible. Ignoring the obvious issue with your output power measurements.
3:45 , you forgot to speak about the Energy efficiency of the motors ^^ It make a significative difference. Biggest generators have better efficiency. The type of motor winding and there characteristics are also a part of the equation. . . But i understand that you want to keep it more simple
On top of what others have pointed out, have you made sure you're inputting the same amount of wattage into each system?
Sure, the small one produced less, but how do you know this isn't just because you were inputting less energy?
How about high speed gear ratio spin with big generator? Does it make better than before?
Do you carry out live streams?
Das pretty sick man.
there's a problem in your calculating .
When you measure the voltege across the motor , the internal impedence's motor is zero.
Because it's like an open circuit (the impedence of a multimeter has to be very high, in this way the current flow is almost zero).
So you can get an accurate voltage's value.
But when you connect the motor to the tester, for measure the current, in this case the impedance of a tester is almost zero, so the motor sees two impedances, that of tester and internal motor.
You have so a drop voltage that you're not considering.
I love how the video ends at 4:20
why are you not using the same motor on both version ?
i think bearing will help to use handle and improve the stability and use it insted of manual pusing gear using hands
Any generator will provide more electricity if driven at a higher speed but there will be an optimal speed above which the output will begin to fall as mechanical and electrical losses increase. The losses will appear as heat.
2:33
And what that current flows through?
Through the multimeter.
The short answer is yes, unless it has a voltage regulator on it. Because otherwise a alternator would create more voltage as rpms increase, but it doesn't create more than 14.?? Volts at any given time.
what if you connect the small motor into the place where the handle of the big generator is and power the small motor with the current produced by the big generator
As a control I think he should be using the same generators for both gear ratios. Metal and nice bearings will help so he can crank of them as hard as he wants
Use ball bearings from rod to gear, for smoothening the spin
What would happen if you swapped the gearboxes though? Which would make more power then?
Can you like make gear box like this which like makes the last gear spin soo fast that in a hour atleast you can power up your whole house for 10 minutes, it would be such a energy saver
Did you measure the force applied ?
Damn, the devs knew what we would try to do. We will find infinite power!
He can try using the power outcome of the gearbox to spin the gearbox.
Which motors didi u use
Seems counter intuitive because I thought the equations would be related to KE = 1/2 mv^2. The fast gear spins 15 times faster than the slow one. 15 ^2 is 225 so I expected the fast gear would create more power. I thought all energy variables (kinetic, potential, electrical) were interchangeable such as watts and joules.
Conservation of energy works everywhere. Did you account for the mass that is being rotated in both accounts? And also the efficiency of the motors to convert mechanical energy into electrical energy?
@@mindprobe3587
I wondered about the mass comparison of the last gear and how this translates to the energy of flywheels of different mass.
Hi, sorry to be THAT guy, but to messure watts, you need to measure volts and amps at the same time. Because, when you load a power source, the voltage usually drops from an open circuit.
4:20 He clearly is a cultured man.
Try increasing the length of the lever for more of that sweet, sweet, leverage.
Why you did not use the fast gear box for big generator?
Can you do high torque instead
Yes, please make the solid version.
Its interesting, in general we could describe de open load voltage of a CC machine in terms of speed and exciting magnetic flux, for permanent magnets we could say that the magnetix flux is going to be constant, so your open load voltage is going to be speed dependent only. Besides that the amount of mechanical power you inject in a system is equal to torque times rotational speed en rad/s. You have to consider that the amount of mechanical power wasn't exactly the same for both cases. Whatever it was a nice experiment though :) .
You should try this with planetary gear sets
hey i made a generator like you with small motor and i can measure the output but i cant use the output please help me
how do you make a gear spin forever
If you make a model out of metal try to get the tolerances as tight as possible
4:20 vid length. Nice
which 3d printer do you use?
But if you tweaked the fast rpm generator to have a little more torque and less speed couldn’t you use the large generator with the faster rpm? Or am I missing something mathematically
All direct contact 1 gear to motor must spin a dc motor up to at least 1800Rpm up to 2500rpm for the ebike 250w motor show.
So unfortunatelly, you didn't have a proper test in this video.
You should use heavy duty gears with 1:50 RPM ratio.
EVERY 30 TURNS FROM YOUR HAND WILL PUT OUT 1500Rpm to the motor.
Try to design helical gears instead of spur gears.
And use three phase ac motors for your diy project.
Dc brushed motor generate sparks that will damage your brushes in a short time if you use a brush dc motor as a generator.
This is why wind turbines are three phase ac motors, no brushes reguired.
I know you are good guy. And I understand that you could not afford heavy expensive gears. That's ok.
Anyway, nice to see your little diy.