I made the MOST EXPENSIVE 2207 motor (with 100% Silver Wire) and KILLED IT 😭

[@FPVKrash]

Instead on chemically removing a more durable enamel, you could use sandpaper or emery cloth on the ends of the wires to get that enamel off as solder prep. It’s inelegant but it works.

[@SmileyFace01]

wont fire work too?

[@FPVKrash]

@@SmileyFace01 Fire sure would work. Too hard to control where the enamel stops burning off though. You would get much more precice control of where the enamel remains by sanding.

[@SmileyFace01]

@@FPVKrash Well when burning the enamel off I still like to sand it a bit.. so It's probably just an unnecessary step

[@FPVKrash]

@@SmileyFace01 Only time I’ve burned enamel off wire has been when I was rewiring a fencing foil, but it doesn’t matter if a bit more enamel comes off in that process. Having burned enamel off wire, it’s not something I’d ever try on a motor wire. Some folx sanded their wire after burning enamel, I never did and always had great conduction.

[@clockworkvanhellsing372]

​@@SmileyFace01fire may lead to oxidised metal making a bad solder connection. Sandpaper ist better, but at that wire thickness using a silicone abrasive disc from proxxon may be the easiest was.

[@kelvinlee7956]

great experiment Chris! I used to made 4 x 2207 with silver wire for Mr.Steele. I remember he told me the performance is similar to a normal copper wire motor. that's why we didn't make it to the market. it is also super expensive lol

[@robertsmith2956]

It is worth if for winding guitar pickups though. It is more sensitive, and gives you a wider range over copper.

[@computerman4321]

I lost and crashed my quad which left the ESC buzzer on for like 30mins and burnt out three of my motors. I naively thought it's just a matter of buying some cheap copper wire and rewinded all three only for the motors to smoke again! Turns out you have to get a particular type of enamel insulation that's high quality as what I noticed happening was the stator core scratched off the cheap insulation due to how sharp it was. In the end, it worked perfectly and I got my motors back but I couldn't match turns count of the original windings, just not tight enough and the KV was a bit off to the original. But it's good to know that if I ever ruin an expensive set I can get them working again

[@krautergarten4529]

Its highly recommended to press the wire straight in the slot after each half loop and not loose tension. If u don't do that u will have a little slag in each loop, so the wire will be moved by the electromagneitc forces, that rubbing will drasticly lower reliability and increase noise. And u will have a gab between the first layer and the tooth, so u can't reach the maximum possible fill rate. The heat transfere will suffer to. U can fix the slag by adding a drop low viscosity epoxy, but that is not a clean solution but will increase motor life. Epoxy easily peals of if u have to unwind it. A better fillrate with copper will alway beat silver. Copper wires are avilable in finer diameter steps so u can max out the winding space better. 😉 Most potential to increase powerdensity (lower weight per Nm) u will always find in the magnetic circuit. Hind: smaller air gap.🤫 And hand wound motor always beat machine wound because u can always squease more windings in by hand. 🖖

[@krautergarten4529]

Most important tool are broken probs. Use the prob blades to press wires to the teeth.

[@The_1ntern3t]

​@@krautergarten4529Broken props are so versatile lol. Other uses are motor wire protection and of course as a stabby tool.

[@combinacijus]

Assuming motor is designed to the limit, would smaller air gap still increase performance if the magnetic circuit is already saturated at max power?

[@krautergarten4529]

@@combinacijus The magnetic circuit should never be "staturated" in a good design, that would cause high losses ... bad efficency but high torque density in some limits. So u always have some kind of design wiggle room. Smaller air gap will give u higher flux in the air gap. Or the same flux with thinner magnets -> lower weight. These rc motors are never designed for max efficency or power, they are designed to be cheap. U will never find room for more copper in a good motor design. But u are right, u will never know which materials were used for the stator lamination or the flux return ring, so increasing the magnet grade or the thickness has some limits.

[@krautergarten4529]

@@The_1ntern3t If u need a stabby tool for ur last windings u know that the motor will rock🤘 or burn 🤪

[@sylaswojciechowski6895]

How about an experiment showing the differences of a neat vs loosely wound motor? I remember flying old emax motors years ago and those windings were messy as can be.

[@taavituisk8452]

You can pack more copper into the motor when it is neatly wound.

[@adamrobertson7215]

@@taavituisk8452 Is that the intention though if you need a specific number of windings?

[@toolbaggers]

@@adamrobertson7215 For the same number of turns you are able to use larger gauge wire (more copper) or are able to make a smaller more efficient motor with less air gaps if using the same amount of copper.

[@unknownhours]

@@taavituisk8452 Due to larger air gaps, messy winding will experience lower proximity effect, and thus lower effective resistance (the coil will also be higher Q, if you care about that).

[@superduperjunde]

@@unknownhours so which effects outweigh?? Are there applications where windings are purposely made more loose?

[@dekutree64]

I have a similarly expensive 2208 motor on my to-do list, making the stator out of mu-metal foil. Theoretically it should produce much higher magnetization for the current, allowing use of higher torque for the same resistive heating.

[@dalegifford18]

So how expensive was the "Most Expensive 2207" (Not including all of your time)?

[@jtcustomknives]

That’s not a lot of silver. Silver at between $20-$30/oz I’m guessing it’s $5 worth of silver.

[@M-H433]

Hmmm,good question,so 5.00$ is that correct?

[@RCOverKill]

​@@jtcustomknivesyea, but that doesn't include making an enamel coated wire from it.

[@M-H433]

Would actually be good to know actually how much the enamel wire is,just out of curiosity.

[@RidiFPV]

​@@jtcustomknivesplus he said sterling silver, so its not even pure

[@victoryfirst2878]

I tip my hat off to you Sir for trying silver windings. I would bet that using teflon insulation on the sliver wire would give you an honest test with very useful information. Good day Chris.

[@jacobsoby3910]

Silver has a lower resistance, so you would have to add more turns to match the original windings, which is why it smoked, you needed a higher diameter wire with the same number of windings. Start with ohms law, combine it with watts law, and determine the appropriate number of turns and diameter based on the current you were pushing through.

[@PiDsPagePrototypes]

Yay. There's someone here who understands where the electrical issues are. (I stuck to the economics vs performance difference)

[@geekswithfeet9137]

That only applies in a stall condition if that isn’t obvious to you then you don’t know nearly enough about motors

[@jacobsoby3910]

@@geekswithfeet9137 Actually, it's called steady state, but ohms law absolutely applies to A/C, you just have to calculate the RMS value for the frequency you're using, and determined the maximum load the wire can handle. With brushless motors, you're creating an electrical short with every pulse, at 100% throttle, there's little to no resistance coming from the controller, and it's like apply the battery directly across the wire for a moment. You can do it, but over a shot period of time the wire heats up and melts the coating even with the pulses.

[@geekswithfeet9137]

@@jacobsoby3910 so inductance and back EMF don’t exist? Lol, KV what is that?….. clown

[@jacobsoby3910]

@@geekswithfeet9137 The inductance is minimal, and when the coil is fully energized, it becomes an electrical short. KV is simply the number of 1000's of RPM per volt.

[@mbug7973]

This was really interesting! Thanks for investing your time and money to make such a cool experiment!

[@michi386]

Hey Cool idea to compare the different material against each other! When the motor doesn't spin up right, like your silver one did, you definitely are having a problem with either a short to the stator or a miss-wound coil. There's also a little trick for winding the AaBbCc style windings. After you completed the first two coils for phase_one, start with the second phase right after that and then the third...With this technique you only have to wind in the middle of two wound coils once!

[@adrasx6999]

To get rid of the enamel you can also use sandpaper, or burn it off with a torch. No need for nasty chemicals. I could also imagine that acetone could be used to dissolve the enamel

[@bren42069]

little motor gone to fpv heaven, where all the enamel is perfect and there's no resistance

[@ColinWatters]

If the number of turns is the same I would expect the Kv and RPM should be fairly similar. Silver has a slightly lower resistance than copper so there should be a very slight improvement in efficiency of a few % as you found. This might be worth it for some competition classes? One issue is the diameter of the wire... a very small change in diameter due to manufacturing tollerance can have an effect on the cross sectional area and resistance.

[@adrasx6999]

"I didn't find rewinding the motor was that difficult" - Kinda funny how you start with this sentence and end up with all the little details which make it really fiddly, ending in the conclusion that you rather buy a new motor instead of rewiring it :) The diagram isn't very complicated, it's these little details like wire the coils nicely etc. Great job though! Now I can finally wire my own

[@adrasx6999]

I don't know if it's the cheap motors which I've got, but you windings look way better than the factory ones I've seen

[@williamgambill3922]

silver plate copper works just as well as solid silver with the exception solid silver may run a lil cooler. electricity travels on the outsides of the strands not the center.the differences in winding patterns (how tight and neat)is the biggest problem to keep the test fair. but if two Motors were wound identical one with silver-plated copper and one with just copper there will be a 5 or so percent performance difference in efficiency torque and RPM

[@JohnDlugosz]

My immediate question is: how does the conductivity (low resistance) of *sterling* silver alloy (92.5% silver) compare with atomically pure silver. The Title of the video says "100%" which is wrong.

[@ssnerd583]

indeed.....925 isnt pure silver

[@DibutilFtalat]

Try Litz wire and compare! It should work better than silver, the conductivity is the minor factor compared to inductive resistance.

[@jsalsman]

In my friend's lab where they use silver coils for micromotors powering biofluidics, they insulate with ceramic instead of enamel or epoxy. I don't think it's for heat, though.

[@visioneerone]

I see that the patron money be kickin in. 😃

[@benjaming9835]

I used to build my own brushless motors from old CD-ROM motors & Neodymium Magnets, because brushless hobby motor were very expensive or too big. I was very surprised to see your two winding methods! Normally I'd wind each station the same direction and then each other station would be another phase in turn, so the same phase is never next to itself. This is easier to keep track of what's next to wind, I never did mark up the stations, (but good idea). It's good to use different coloured wire for each phase too. btw you burned out a motor, can't be sure of course but if you make mistakes in the windings this will lead to coil miss matches that always end in burning out the motor.

[@HughCStevenson1]

You can always test a hand wound motor by driving it with a drill and measuring the back emf with a scope!

[@BentProp_fpv]

Holy cow! I wanted to re-wind some of my burnt motors but didn't get round to actually do it. After watching your video, I finally started with one of my motors and WOW! It spins! 😳 It's even close to its original KV value! That is such a satisfying feeling! Altough it's really a lot cheaper just buying a replacement, it is definitely something, one should have done! Too bad you didn't capture what happened to your silver wound motor, there must have been a lot of smoke 😅

[@robertsmith2956]

or showed how much easier it is to wind the silver being a softer metal.

[@sunsetpark_fpv]

Awesome job Chris. Just the fact that they spun after being hand wired was great. So many variables to deal with.... Is there a Chris Rosser signature motor in the near future? 😁

[@razzreal_fpv]

definitely one of the more interesting and better videos, this was cool

[@CarbonGlassMan]

That was a LOT of work you had to do for this video. Cool test.

[@iclazion]

After watching this intriguing video, I couldn't help but wonder if we could create something extraordinary. Imagine taking a long copper pipe, delicately threading silver wire inside, and then drawing the copper tube through a die to stretch and wrap the copper around the silver. The result? A fantastic foundation for winding the brushless motor. The beauty of this idea lies in having the silver securely embedded within the copper, ensuring it stays put even if it approaches its melting point. I hope this idea works :)

[@MetatronsCube23]

electricity flows over the surface of the wire not inside of it, hence the silver coated copper. It melted because there was a flaw somewhere in his winding.

[@thomasmaughan4798]

@@MetatronsCube23 "electricity flows over the surface of the wire not inside of it," Direct current flows through the entire thickness. Radio frequency energy travels mostly on the surface, how deep it penetrates depends on frequency. en.wikipedia.org/wiki/Skin_effect "At 60 Hz in copper, skin depth is about 8.5 mm"

[@stanleydsouza6723]

We the enthusiasts the world of innovations always pray for much more and prosperity ..God bless 🙌 you buddy

[@dfgaJK]

If winding silver wire why not use the twisted pairs to go to the esc rather than soldering ti copper silicone coated wire?

[@FPVKrash]

Good point. If you’re winding your own motors, why not keep it super clean and not add unnecessary joints. That could end up as a super-sick build but personally, I wouldn’t be able to handle it if I clipped a wire too short when soldering to the ESC. 😅

[@dfgaJK]

@@FPVKrash Imagine, and you know it is going to be the last wire of the last motor that's too short! And the agony deciding between an ugly little extension or rewinding the motor 🤣

[@Inertia888]

@@dfgaJK 😂Stop. Put it on the shelf. Forget about it, and start building an entirely new quad. Get board, and pull it off the shelf, to get winding again.

[@guytech7310]

You can try different winding wire formats, such as litz wire & flat wire. I am not sure what the switching speed of the motor coils are, the skin effect can reduce current flow. Probably with flat wire you can increase motor torque.

[@guerrillaradio9953]

It might not be your handiwork that failed on the pure silver motor. It could be that due to the decreased resistance, for the same load, voltage, and PWM duty cycle was all the change needed to push the current draw into the danger zone.

[@marc_frank]

you can also make 1,4,7,10 one phase then 2,5,8,11 and 3,6,9,12 (for the star configuration) i wonder if connecting a ground wire to the star point would reduce electrical noise

[@PiDsPagePrototypes]

Probably do the opposite, and give the AC 'noise' a direct path in to the DC circuitry.

[@bobwatkins1760]

I don't know how England does windings but here in USA we use a poly coated paper in between the stator spaces to assure when we wind or rewind a motor stator there is almost no possibility of short due to sharp edges on the stator area. I was thinking when You were doing that winding that You'll probably get a short.

[@koolaidsrequiem9646]

Couldn’t you use a fly bobbin to help in winding the wire, I don’t know if it would work but just a suggestion. It would keep your hand from cramping and maybe speed up the process.

[@baraBober]

You have to try again and compare the output of solid silver vs silver plated.

[@sethschneider9764]

I've been looking forward to this video since you announced it. Thank you for doing this. I have a few probably dumb questions. How would having multiple layers of winds on a stator affect the motor? I'm not sure if this affects how the motor fundamentally works and is out of the question. This would obviously be pretty difficult on a small motor like this, but you could possibly add another layer just on the outside portion of the stator. You're doing great work man keep it up!

[@Chris-oj7ro]

HAHA, YOU DID IT!! and so quickly too! I love it!

[@conorstewart2214]

You can just sand off the enamel coating too so you don’t need the solderable wire. Or if it needs a higher temp to burn it off then maybe a lighter or mini blowtorch would work

[@Eleanor25589]

nice to see how much fun you have doing this stuff.

[@DavidOwensuk]

I admire your dedication!

[@butterflyfpv]

Thank you Chris! Great work!

[@MCsCreations]

Fantastic testing, Chris! Really interesting indeed!!! 😃 Stay safe there with your family! 🖖😊

[@conorstewart2214]

Technically I think you could wind all coils with a single piece of wire. Wind one phase, leave a loop or tail hanging out then move onto the next phase. Since all phases are electrically connected it should be possible.

[@billmcdonald4335]

Next week: Chris tries winding a motor with Cavorite wire. . . provided the dilithium kididdle meshes with the grapple grommet. Wizard.

[@FourthWayRanch]

doesn't it have to do with the magnetic field not conductivity? wouldn't it be easier to just wrap different wires around a pencil and see how well they pickup iron filings?

[@BrightBlueJim]

Did I mis-hear, or was the silver motor erratic even on the initial unloaded spin test? I think it had a shorted somewhere from the start.

[@neail5466]

lovely, very much loved your experiment. coul you please tell how did you open up the motors? I don't see any circlips!!

[@JoanMendoza]

Thanks for doing this! I look forward to your video on silvers properties :)

[@zunairsajjad7098]

You are really good teacher you deserve better 👍

[@poiu477]

I just started this video, was interested by the explanation between silver and other metals, so you can imagine my elation finding out the algorithm showed me this vid 20 minutes after the other went live!!!!

[@rohansully584]

Nice work. Thanks for doing it!

[@sgodsellify]

You need to make wire that is also laced with Holmium as well as Silver. Holmium has the highest magnetic moment, and combined with the 5% less resistance that Silver brings to the table, then overall a motor that is wound with a wire that is Silver/Holmium, then that motor should use 30% less energy to produce the same results from a copper wired wound motor.

[@1kreature]

One little mistake: You did not test all 3 bells on all 3 motors. The magnets will vary a bit in strength and alignment and the 2% variation can easily come from that. Measuring the motor Ri would have been very nice as one can then easily calculate the efficiency curves.

[@deltapag5051]

Do you have a price comparison of copper, silver plate & solid silver magnet wire? It seems that silver plate is the way to go.

[@stanleydsouza6723]

Beautiful, valuable information and more on using silver..Thanks Brother..

[@williambrasky3891]

You can use sandpaper to strip enamel off the ends of the wires.

[@Athiril]

Theres actually a wire with lower resistance than silver, I've forgotten what it was but it was some kind of doped material

[@GinTonicFPV]

Hi Chris, do you think we may see axial flux motors for miniquads in the future?

[@marc_frank]

that would be cool i've been thinking about how the stator laminations could be simplified for such a motor, but haven't found a solution that's one of the problems that have to be solved before they are introduced

[@danspratt2]

interesting stuff dude! Do you think you could change your mic settings to lose the lip smacking sounds? I dont know if its just me that finds it hard to listen to (12:57-13.01 as an example)

[@modquad18]

Ugh, why did I have to see your comment. Now that’s all I hear 😫

[@Prince_3530]

a great experiment i literally searched this thing many times about 2-3 years ago but didn't found any answer about this . you did a great job but remember your mistake was silver is more conductive hence it will need more turns on each and every pole of the motor then previously wound copper coil . and can you do this again with more turns of silver wire or you can just use thinner silver wire so that we can see that science in a practical way . thanks for this video.

[@FINNIUSORION]

great stuff. I haven't re-wrapped a motor in over a decade at least lol. there's so many companies now making so many different types of motors it's not worth the time and effort anymore.

[@PackthatcameBack]

Wait, heat is caused by high resistance in wires but silver is the most highly conductive of all metals. How does that go together?

[@butcher]

Wow maan, what an awesome content, you are brilliant :D

[@wolframzirngibl1147]

Just guessing. In case, you manufacture a silver wire motor, you have to do the very same with all the other wires. The difference in resistance between copper and silver is in the 10% range. So, using 3 (phases) thin motor wires in parallel of 100mm in length cannot outperform even thicker copper wire of 400mm or more effective length battery - ESC - motor. Second, I doubt, if any ESC will do a ultimate %-grade auto-timing optimization if firmware-configured with typical outrunners using copper?

[@ah4quadssake885]

Have you tried comparing motors in a "wye" or "delta" configuration ? Huge differences in output power 🤷‍♂

[@williamfraser]

Just wondering about the switching frequency and possible skin effect. If frequency is high enough for skin effect to become a problem, the silver plating on the copper wire would be conducting a higher proportion of the total charge.

[@HolmesHobbies]

In the coils it's just the commutation frequency, as the inductance smooths pwm frequency to be almost nil. So skin effect in this size of motor inside the coils is not really a factor.

[@KCQuadTronX]

thanks chris for a great test vid

[@petrokemikal]

Chris you should do a video on a few of the dirt cheap aliexpress motors floating about.. Id love to see what some of them are like.. I just seen a couple of micro brushless motors there recently for like 4 bucks a pop.. Could make for the ultimate budget build..

[@Bruno-cb5gk]

I think what would make more sense is silver plated aluminium wire. Aluminium has the lowest specific resistance,and since the outside of the wire has the most current going through it having the silver only on the outside should still give an improvement without as a big a price increase.

[@HolmesHobbies]

From within the motor, inductance smooths out pwm to where coils really just see commutation frequency. This means that skin effect is almost nil. Commutation is generally not above 500hz, whereas pwm may be 8k to 22k.

[@HughCStevenson1]

Precision DC resistance measurement of the coils would be interesting

[@Gavs_rc_hobbies]

Awesome video. I have an old motor off a quad that seems to be faulty. I migjt have a go at rewinding it.

[@EugeneWangombe]

Where did you purchase the silver wire from?

[@yowild9629]

dealing with system losses can improve eficency using switching mechanism that is Reactive to watage instead of current

[@laurentbeaulieu2446]

Is that wire also available in gold?

[@k4x4map46]

Wow!! Just changing a unibell has me sweating lol gonna need a larger motor myself great stuff!!

[@Alexander_Sannikov]

you can easily strip enameled wire with a knife or some sandpaper

[@gog2462]

instead of using silver or gold or any more conducting windings just use bifilar copper windings for example instead of use one 0.4mm2 copper wire use like 4x0.1mm2 wires it will increase all params of any electric engine - the problem is it is hard to do this because you need to have exact len. of all copper wires on all coils.

[@ProximoFPV]

Hey Chris, is it possible you make a video about how to make your 5inch race quads lighter? I've been thinking of ways to cut weight and was wondering if you have any ideas I have not discovered yet. I've seen a few pictures of MCK quads being insanely light with some secret motors? Not sure exactly whats going on there but Im super curious if you have any insights.

[@simonlinser8286]

Isn't the difference in conductivity so little it doesn't matter? Why not a silver copper alloy? Wouldn't a very high purity copper be comparable in performance? If the silver burns out more easily isn't it actually less efficient if the motor breaks?

[@archietheproto7706]

My question is is it really more efficient though, because silver is denser than copper

[@Plur307]

T motor makes motors with silver windings. I believe older models of the F40 pro had silver wire.

[@jakub9916]

Will you make 7" motor test?

[@iammeuru]

I know this was a tremendous effort, and asking you to do it over would be ridiculous, but I'm still very curious what the final results of a functional silver wound motor would be when compared to the others. Too bad it didn't work out. Thanks for the info.

[@PiDsPagePrototypes]

Very little difference, because it's only a few percent lower resistance then Copper. The change in dynamic balance compared to the factory made machine-wound motors will have more effect at limiting the RPM and Acceleration.

[@HolmesHobbies]

Agreed, little difference. A few% lower terminal resistance. Easier to wind copper tighter to get that vs silver wire. Can't really pull silver wire as tight. More gains can be had from magnetics improvements

[@iammeuru]

@@PiDsPagePrototypes sure, but sometimes a few percent is enough to justify a cost to some people. I mean, there are certainly people out there who would pay the increased cost for that extra few percent for a factory machine-wound silver wire motor. I wonder if it's possible to get a machine wound motor (not at retail, but a one-off set) for testing against the same motor made with a copper conductor... If we wanted to know the no kidding performance increase, contacting might be the next step; in fact, this might've been the best first step to get a set made to compare apples to apple. That single set will likely be a few to several hundreds of dollars, and likely the best way to get them made would be to run a small group-buy, or run a small batch to sell as retail to bring the per unit cost down significantly, at a steep upfront investment cost. I'm pretty new to the hobby, but if someone wanted to do such a thing, and chose a good motor as the foundation, I'd likely be willing to buy a couple sets to have for myself if the cost/set weren't more than about three times the cost of the same motors in copper. One of my other big hobbies (high end mechanical keyboards) is pretty much all based on group buys, so I know Chinese manufacturers are pretty willing to do this sort of thing, and the hard part is finding someone willing to do the leg work to go through the process.

[@PiDsPagePrototypes]

@@iammeuru outside of electric pylon racing, the percentage difference is not worth the time, money, or performance advantage, because the mass difference will have greater influence on a motors ability to change speeds. Until ambient temperature superconductor wire becomes available, Copper will remain the best choice overall, for all but edge cases.

[@iammeuru]

@@PiDsPagePrototypes huh? there is a weight difference between silver and copper, but it's going to be pretty small given the volume used on these motors (max of maybe 1g/motor?), further this is all contained in a non-rotational part, thus not effecting the speed the motor can accelerate. Your cost analysis isn't necessarily the same as everyone else, I suspect there are plenty of people who don't exist at the margins where this is useful to them, but who would still be willing to buy some of these motors. I am someone who would probably be willing to buy a set of these motors (factory wound) even if it drove the cost to double to triple/motor... I wouldn't build a fleet of units with them, but I'd definitely be willing to do it for a dream build, even if I wasn't realistically going to take full advantage of it... If I were rich enough to where it wasn't a significant drain on my bank account I'd buy a McLaren P1 or Porsche 918 Spyder even though I'm not capable of taking the car anywhere near its limits; I mean even at a much more "for the masses" example, people buy large trucks to never use them as anything but a commuter every day. As for the time part, the reason we would want to know the numbers is because it would be possible to get these motors produced (factory wound) if there were a definitive demand, which would be driven by knowing what the performance difference is, and marketing it accordingly. The time difference would be non-existent if they just came that way in a box. Also, we are not the best community to use as an example for people who consider their time to be the most valuable resource; think of how many people build rather than BnF.

[@TheOriginalEviltech]

Can you try winding a motor with Litz wire? I would love to see how it performs in a motor!

[@cch201992]

I like to see people try stuff even if it's expensive because that tech could change the world and would lead to more people working on bringing cost down of the raw materials I like to see what is the best ultimate version of anything I hate when cost was the limiting factor of a design

[@multimargejta123]

Where can I buy enamelled silver wire?

[@anunnakielohim2727]

Any idea if a braided wire wound motor would be better than a solid wire wound motor?

[@colinjohnson5515]

Solid is better. I think it has to do with higher cross sectional copper density. You want as little air gap between each winding to increase flux density so I assume the air gap in multi strand wire would lower that density. Braided/multi strand wire also has higher resistance which lowers your efficiency.

[@tk-maker]

Wow, most useful and detailed info about winding a motor, i got one XING2 awaiting rewind. thanks

[@annoying_pyro_]

@Chris Rosser Thanks for great educational content. I have a question about motor RPM. As you explained in motor KV video, the motor RPM is limited thanks to back EMF, which is negative voltage that prevents the main voltage from creating a current draw. But what actually prevents us from just applying more voltage to the motor to exceed back EMF and get even more RPM, assuming the power supply/ESC can handle it and motor is free spinning (or, more strictly, the useful power is small enough so that the actual current draw for the voltage applied is below some point where the motor starts to melt)? And if that's actually the way then what is a point of motor's voltage rating aside from just being a recommendation for typical usage in drones? (I suppose this should have been asked under the motor KV video, but now it feels more likely to get some attention here.)

[@thomasmaughan4798]

"But what actually prevents us from just applying more voltage to the motor to exceed back EMF and get even more RPM," Nothing at all prevents it. The KV rating is the RPM *per volt* so if you double the voltage you double the RPM. at some point the motor will self destruct.

[@annoying_pyro_]

Thank you for your answer. I wonder then what the motor voltage rating is intended to mean.

[@luclachapelle3499]

Well done ! You should also compare using Litz wires All tests should be done using the same current

[@simontillson482]

Litz wire is not going to improve anything - the frequencies at which it would make sense are in the megahertz range, and motors work in the low kilohertz at most. The skin effect is almost absent at this frequency, so even using silver plated copper is dubiously advantageous at motor speeds. Eg. Maximum fpv motor speeds are around 30000 rpm, which is only 500 Hz. Skin effect only starts to become significant at 10000 Hz.

[@BobWidlefish]

To be a perfect test you should have rewound the first motor too, to make sure it wasn’t the winding process you used that introduced any bias.

[@gloorfpv1801]

Hey this is a really cool experiment,,, I learned something today

[@justfly7730]

You killed it with that video. 😅

[@elijah4666]

the dust wasn't graphite was it?

[@MountaineerFPV]

Sterling or 3 9’s fine Silver???

[@cinemoriahFPV]

3 9's

[@Jonas_Aa]

If wire was flattened and made more square or rectangular there would be less ar between the wires in the winding. Wonder if that is possible to do. I have seen huge generators use that technique. I think the wire is a little rounded in the corners so they are not too sharp.

[@wolframzirngibl1147]

As said, with huge generators you use huge wires. Try to find a 0.x square wire shaped rectangular. I did not succeed.

[@Jonas_Aa]

@@wolframzirngibl1147 sometimes people make their own stuff on KZbin.

[@JoeSmith-cy9wj]

I don't have the data but I suspect pure or fine silver is a better conductor than sterling, which has over seven percent other metals.

[@silkjamfpv]

Nice video Chris!! I really want to rewind a damaged motor i have just to see if it works like a challenge and to learn more about motors. I got the copoer wire already ....so good timing for this video!

[@paulroberto2286]

Dracula has been real quiet since this dropped...