Brushless motors in the lego world - general topic

[Knott]

So, I did my first proper test run today, shredded only one 16 gear after 10 minutes, surprisingly this time the shaft survived and stayed straight

 

[DadScientist]

@Knott

a.) I was looking at your twisted axle from April... that's impressive!

One suggestion I thought of was to use the metal U-joints from Metal Technic Parts: Their design is basically just round-hole with set screw, which might allow you to just use plain round metal stock, as long as you file a notch for the set screw. Could be aluminum, steel, Ti, whatever... 

But it looks like you have the axle problem (potentially) licked. 

b) Wanted to say thanks for the tip about heating up a bearing and pressing it in. I was trying to wrap my mind around using a precision reamer, or something like that. This is much better: No plastic removed, no strength lost. What kind of aluminum rod did you use? Just 3/16" rod, or something else? Any other advice for keeping the bearing centered in the hole while you squish it in?

 

---

Other than all of the above, just wanted to say hi to the community, and say thanks for sharing everything in here! So much good information... I'll try not to gush. This time.

I've been trying to figure some of this out for months. I haven't touched RC cars in years, (pretty sure it was 1988) so a lot of the brushless motor stuff was all new to me. (like kv ratings...) And I'm now starting to appreciate some of the options with the transmitters now, too, like adjusting throttle-up curves. I have so much to learn... 

I started with building a copy of @janssnet's brushless buggy from youtube. It was a long, drawn out process, with a dozen screenshots printed out for reference, and occasionally loading up youtube on the TV, so I could get a better view of what was going on. All of the black framing looks so cool... and it's so hard to see contrast. But eventually, I got there. 

I made a few modifications: This version is longer than his, because I the motor came with a 35A car ESC, instead of the small drone ESC he used, so I needed room to mount it. I used planetary wheel hubs, because I was worried the torque from my oversize tires would torque the axles too hard. (I've since tried straight up, axle to wheel... my instincts were right.) I had to modify the front suspension to use Lego's roller hubs, which are taller than the steering hub @janssnet used in most of the builds I found on youtube. I also had a simpler rear suspension, becuase (at the time) I didn't have the big turntable.  Lastly, I did something different on the back of the front suspension that required the longer stop axles.

But holy cow, the amount I've learned from following all of the bread crumbs in his videos. I'm incredibly grateful. 

It hasn't been easy. And I think for newcomers I'd probably recommend just going with the Zene motor. (I haven't bought one yet, but I think I will. But having seen @Knott's twisted aluminum axles, I'll stick with using just the one. ;) )

I built a second version, shorter, with a 2838, and yellow technic beams, and black panels. So far, it's had more luck, but it's been taken apart so many times, the pegs are starting to loosen. I just rebuilt it, and got the drone ESC that I'm pretty sure he used, so that'll go back together soon.

I also just built his version of the 42124 buggy, to take a break from that one. But I built it with a 2838 motor, instead of an outrunner. So far I'm busily stripping 8T gears, because I haven't figured out how to lock the motor in solidly enough. A little vibration throws the end of the motor around, and then the gears don't line up as well as they ought to.  

I've learned a lot in this process so far... Use silicone, not lithium grease... And DEFINITELY pay attention to motor kv rating....

"But that 2430 motor is SO DINKY! How could it possibly WHOOOOOAAAAA.... "

(7200 kv. When I bought it, the concept of kv was something I didn't understand yet.)

And on and on. A lot of busted parts. Axles welded into holes, melted and snapped, and beams that either welded themselves to the axles... or dissolved, (thanks lithium grease!) deposited themselves around the axle, and were left with a big, wallowed out conical hole.

One of my favorites so far was the melted homemade pinion. (below) Literally melted down through the clearance hole, into the motor casing. I still hadn't figured out how to mount a pinion to a 2mm hole, other than drilling an axle. (See also, "7200kv") Note the melted plastic around the hole... and the melted half bushings that were meant to help keep the axle in one piece... and the drip of axle plastic, coming from between the pinion and the bushings. 

For now, future experiments will involve bronze bushings, ball bearings, and drilling a 2M aluminum axle to fit onto that 7200 kv 2430. Maybe if I can learn enough about changing the input curves, add enough ball bearings, and perform some sort of ritual sacrifice to the gods of speed, I can tame that little beast and make something that really cooks.... and hopefully for more than a minute. 

(Then I'll try very hard not to mount it into that Mario Kart kit, and crash it into the Lego store at the mall.) 

 

 

 

Edited July 8 by DadScientist

[Knott]

Don't push the bearing, pull it in!

Bearing (red) should be pressed or even hammered onto one end of your 32 stud long AliExpress aluminium axle quite hard, you can grind the axle with a file later for it to float over the bearings but for setting the bearings with heat it's perfect to just hammer one bearing that you will sacrifice (it will get clogged with plastic and it's only use will be making holes for other bearings to sit in) onto axle so it stays firm.

 Create a sandwich of 5-8 (blue) liftarms with the piece you want to modify on top (yellow), place it at the bottom of your 32L Aliexpress alu axle (AAA?)

The more liftarms you use the more centered the bearing will be, but they will get partially damaged. I used a stack of 8 bars 7 stud wide and 3 of them got scorched by the axle, basically they partially turned from hole to cross, cooling parts with water is important

Next thing is heating the bearing, have a wet paper towel or some water to absorb excess heat nearby and use propane torch or regular kitchen stove, basically when I feel the heat with my hand when holding it in the middle of the axle I know it's time to set, grab the axle below the sandwich and pull the pieces firmly towards bearing, (green arrow) bearing should be centered by the other bars below, do it in small steps and cool the bars in between sessions.

Best result is when you sandwich the bearing between two liftarms, so it gets support from two pieces and not just rapidly melting one liftarm halfway in one take, as it weakens it a lot. R156 bearing is about 3,5 mm thick and Lego bars are 8mm thick, so instead melting one liftarm flat with the bearing, rather melt two partially over multiple tries so bearing sits nicely between them.

Remember to clear away any melted plastic with a sharp knife on the outside and drill out the axle hole with a 3/16" 4,8mm or 5 mm drill so it runs smoothly, your axle support modification is now complete.

I have decided to not use u joint on the drive shaft, now 23,5 cm alu axle is transferring power from motors to 1st and 2nd axle, so far nothing is bending so I think previously the u joint locked up somehow and bent the shaft, no u-joint, no problem.

With my current ESC crawling is impossible, it doesn't start smooth but I was amazed by the speed it achieves. On second video I have limited the throttle to 30% and it still handled tall grass like champ. ZENE was supposed to send me motors with 1/16 reduction at my request, but I feel it's probably 1/4 and speed of up to 60kmh is very much possible, however it will melt all parts that don't have bearings :)

I'm very pleased with ZENE motors and differentials, their attachment points and performance.

My next big issue is portal axles, wheels keep detaching as plastic lip on wheel hub gets melted, sadly so far noone is making portal axles with bearings, and there is not enough material on them to DIY it like support bars that I explained above, gotta find someone who can print them for me, as dirt is shredding my uncovered portal gears.

Since original Mercedes uses solid portal axle I tried building it with Lego parts, sadly the axle travel was not satisfactory for me and I built this monstrosity to clear obstacles easier and always keep wheels to the ground. ZENE differentials as the center piece, each rear axle has 8 springs, four tall to hold the axle to the flatbed and another 4 pushing multi link arms to the ground, always compressed by the weight of the car but allowing wheels to drop lower if necessary to keep contact with the ground.

 

Edited July 8 by Knott

[DadScientist]

I'm not 100 % convinced that you can't use a stock lego portal axle, with bearings.

I was looking at some new ones that I just got in the mail the other day, and it looks like the hole where the spindle goes in is ~ 3/8". R166-ZZ is 3/8 OD, and 3/16 ID, and you can even get em in ceramic. So that might just be the ticket.

You might want a bearing on the back side, too, which would be another adventure, maybe use your pull-in technique on that. Or, use a module bush, with a cross block fork at either end, and clip that onto the back of the hub where the wheel axle goes. I'm sure there's enough plastic in the module bush to drill and melt in a bearing. That subassembly would simply replace one of your 3M half-beams. 

But it's possible that 3d printing a tapered ring to backfill the portal and hold the bearing would be enough. Or, you know... baking soda and superglue. Portal axles are only 85 cents per piece. You have to wait forever, what with int'l shipping to USA, but it's not going to be an expensive experiment. Order 50 of em, and have at it. 

So... You might be closer to nailing this than you think.

Where are you?

Other ideas... Maybe chop the bell off of the portal hub, and mount one of these with two of these to sandwich it? I haven't measured, but maybe the large diameter of the bell will hold a skateboard wheel bearing. Who knows?

Of course, you could also try try roller hubs, or planetary hubs. (Lego's nomenclature cracks me up. If planetary hubs are "WHEEL HUB, NO 4," and roller hubs are "HUB, NO 21," then where the hell are all the others?)

 

Edited July 9 by DadScientist
clarity

[DadScientist]

Another random discovery…

Apparently bearings are easier to mount than I thought.

I was screwing around with the big ball joints, and realized they could be pinched this way. ANd I'd just figured out earlier that a bionicle ball-socket fork would hold a bearing. So... I tried this. Works pretty well, without needing to drill or melt anything. 

I still like Knott's melt-in idea, but this might be worth playing with. 

 

Edited July 13 by DadScientist

[Tup4n]

For my next project I decided to use smth new instead of ZENE Bricks motor. Their 500w brushless motor was proved to be reliable and powerfull (I managed to reach 53 km/h on the 1:8 scale car ) but you now this feeling, when you want more and more power and speed. That’s why I picked this one. 800w (60% more powerfull then Zene’s) 2847 3200 KV Ysido with steel 46 tooth spur gear and aluminium axle. This thing is really strong 

 

[sbricking]

hey guys .

i just got a 6S BRUSHLESS MOTOR SETUP 

im thinking of adapting it to lego

the motor is surpass hobby 3660 1750 kv 

i think if i connect it the vehicle is going to absolutely rip

i saw other peoples brushless buildss and i think i went overboard

can someone please help me in adapting it and the build 

please

[Krxlion]

On 8/6/2025 at 11:52 AM, sbricking said:

hey guys .

i just got a 6S BRUSHLESS MOTOR SETUP 

im thinking of adapting it to lego

the motor is surpass hobby 3660 1750 kv 

i think if i connect it the vehicle is going to absolutely rip

i saw other peoples brushless buildss and i think i went overboard

can someone please help me in adapting it and the build 

please

Hey,

6S system is simply too much if you are using Lego bricks for driveline. You will drive for a couple seconds and melt/break axles, etc.
Please browse through our topic, there are plenty of solutions already provided here and there. If you adapt that motor to Lego system - 2S battery will be enough for a start. Then, learn by making your models, testing and see what works for you. ;)

Afterward, you are welcome to share your opinion.

[Ryokeen]

On 8/6/2025 at 11:52 AM, sbricking said:

the motor is surpass hobby 3660 1750 kv 

That's not a 6s capable motor, 4s at max but most likly 3s. 6s motors commonly start at 42mm diameter and at least 5mm shaft. Even if your esc can handle 6s the motor won't(at least not for long). And yes at you can read here in the topic even 2s will be a challenge with lego. 
Remember brushless motors got a lot more punch than brushed ones and the initial torque tends to rip everything build with lego only apart.
In my opinion the 2 most important things are:

• Metal Axles and a good way to connect them
• Bearings to prevent molten plastic even with metal axles. That includes wheelhubs with bearings

[Krzychups]

Hello.

I've bought parts for my new iWD RC car (motors in wheels, exactly what @janssnet has done) and they're currently being shipped. Can't wait to test it out.

Since each motor is in each wheel, I have an idea how to transfer part od the load, for example during jumps - TPU rims. I have no experience with this material so I'd like to ask @Aurorasaurus.

Do you think that this is a good idea? What TPU hardness have you used for your rims? What do you recommend? I think something about 95A - 98A. How the car behaves while driving? Or it's better to do something different?

Thanks in advance.

@Tup4n, could you show us closer this metal gear? Interesting how you can connect it to the shaft. I've modeled my transmission on this one you have. Unfortunately your transmission isn't covered. Why the designer doesn't use smaller 11 tooth pinion instead of 12 tooth one? This way, a smaller spur gear can be used without significantly changing the gear ratio.

[Aurorasaurus]

20 hours ago, Krzychups said:

Since each motor is in each wheel, I have an idea how to transfer part od the load, for example during jumps - TPU rims. I have no experience with this material so I'd like to ask @Aurorasaurus.

Do you think that this is a good idea? What TPU hardness have you used for your rims? What do you recommend? I think something about 95A - 98A. How the car behaves while driving? Or it's better to do something different?

I use 95A TPU because it prints well and is common. Depending on what rim style you're hoping to use, you can probably get a decent amount of damping right down to no damping at all. If you designed the spokes of the rim in an arc maybe it would allow the outer circle of the rim to move around during landings...

But really, I think softer tires will be a better solution. If you're using rc tires, I'd suggest just gluing them to the rim and forgetting about it.

I'm curious to see what you come up with, keep me posted if you will.

 

[keepbricking]

hello can someone please help me in mounting a 3mm motor shaft to lego without mod 1 gear and any machinery

 

[janssnet]

This may help…

[keepbricking]

hy bricks replying to me was something i never expected

sorry but i cant modify my lego parts

i dont have a machine like that

do you maybe have a better solution 

it needs to manage a lot of torque

able to move mercedes g500 at high speed

 

also i dont have a shaft collar like that

 

[Krxlion]

14 minutes ago, keepbricking said:

hy bricks replying to me was something i never expected

sorry but i cant modify my lego parts

i dont have a machine like that

do you maybe have a better solution 

it needs to manage a lot of torque

able to move mercedes g500 at high speed

 

also i dont have a shaft collar like that

 

If you don't have any special tools, I would try this method (from @janssnet himself :D):

I was actually using it 3 years ago, and it was working, but I was replacing this plastic "part" from time to time. 

PS You need a motor shaft to be in "D" shape, without it, it won't work.

Edited August 25 by Krxlion

[keepbricking]

hey guys can anyone show me what zene bearing wheel hub for 1:10 looks like 

i'm thinking of buying it

 

thank you krxilon for your kindness

 I tried with double sided tape but it just won't hold

 

[Krzychups]

On 8/25/2025 at 2:03 PM, keepbricking said:

hey guys can anyone show me what zene bearing wheel hub for 1:10 looks like 

i'm thinking of buying it

Hey, these wheel hubs have a 0.5 stud offset, which makes setting up the suspension more difficult. It's almost impossible to build a four-wheel-drive vehicle. You can only build a rear-wheel-drive vehicle, and you would need to cut drive shafts which go to the U-joint. These snips are enough to cut them. Personally, I prefer something different wihout this offset. I once worked on a project involving hubs without offset, but I abandoned it because I need steel U-joints. To clarify, there are two types of U-joints available on Aliexpress: steel (which I need) and aluminium joints (the ones in the photo). They are sent randomly. I don't want to buy more. Steel joints can be threaded, aluminium ones cannot. 

PS. Thanks @Aurorasaurus for your reply, I'll use non-TPU rims.

Edited Thursday at 09:04 AM by Krzychups

[keepbricking]

thank u very much 

i was ,indeed thinking of building an AWD vehicle

now i think i will buy TF wheelhubs

also random idea :

nobody yet has built a brushless tracked vehicle

maybe i can build one with drone motors

[gyenesvi]

I decided it's time for me to enter the game :) So here it comes, my first brushless motor! A small one to start with.

A few days ago I bought myself a Bambu A1 Mini 3d printer, and started experimenting with making a housing for brushless motors.

Features

• Dimensions: 3x3x6 studs
• Weight: 34 gr
• Reduction: 24x down-gearing with 2-stage planetary gearbox of PF M motor
• Speed: around 1100-1200 measured RPM, but around 1500 on paper

Design

I decided I wanted to base my design on SurpassHobby 24xx motors, based on the ideas of @HorcikDesigns presented in this thread. For me, the ideal form factor is the 3x3 one, which those motors fit perfectly, and because with a planetary reduction, we can keep that form and get good amount of reduction.

So my key idea was to take apart a (3rd party) PF M motor, and take out the planetary reduction for my purposes. The PF L motors also has essentially the same reduction, but its internal housing has a bigger shape due to the L motors bulge, and so I could not use that. I went on and bought a SurpassHobby 2435 3300 kv motor. When I started looking for an ESC, I came across this super small Injora one, and since I used its brushed counterpart already, and I was satisfied with it, I decided to order one (it can handle 25 A continuous and 60 A peak current, 2-3s LiPo, has adjustable BEC output up to 3A, and is waterproof). I realized that there's an accompanying mini outrunner motor as well, they come in a combo, so I bought that as well (17x21 mm only, 2800 kv). The wiring is really plug and play, you just need a battery with an XT30 connector, and a receiver.

To my surprise, the motor comes with a 11T gear that's a perfect match to the gear inside the PF M motor, so it meshes perfectly with the planetary reduction. Furthermore, it also comes with a couple of 2M screws that I needed for the assembly, so I set out to print a housing for this one first.

The housing consists of 3 parts. First is the front face together with the planetary housing.

Second is the mounting wall.

And the third one is the back cover (it's optional, but good to have). The rear holes serve as ventilation openings, as well as they are inverse studs for mounting.

The assembly sequence is as follows. First, the wall is screwed to the motor from the inside with M2 screws that comes with the motor.

Second, the planetary reduction slides into the two horizontal slots of the wall (the planetary housing has two horizontal tabs on the back to fix it against rotation).

Third, the front face can be screwed on at the corners from the back using M2 screws.

And last, the back cover can be pushed into the slots on the wall mount from the back. It's a really tight fit, so it does not come off.

Optionally, the inverse studs on the back can be used to fix the motor or add further mounting points.

More pictures are available on my Bricksafe.

 

I haven't yet built it into any model, only tested the bare motor. The control is insane, it has super slow startup, it can go as slow as about 1 revolution per 25 seconds, but with enough power that I could not stop it with my hand.. And then it can go up to 1200 RPM. I'm really curious how it will perform in a model :)

 

I am planning to make a similar motor using the SurpassHobby 2435, but of course without the back cover, but first I need to buy some M3 screws for that one. Any ideas where to get them in various sizes?

Edited Monday at 10:07 PM by gyenesvi

[2GodBDGlory]

Looks nice! I look forward to seeing that in a model!

[HorcikDesigns]

Nice! Does the gearbox withstand high RPM of the brushless motor well? 

[gyenesvi]

1 hour ago, HorcikDesigns said:

Nice! Does the gearbox withstand high RPM of the brushless motor well? 

Thanks, well that is also a concern of mine, yet to see when I build something with it.. but I have hopes. For one, I have been using modified PF L motors with buggy motor inside, that has the same planetary gears and there was no problem there so far (that has almost this high RPM range). Also, I have a feeling that I am not going to drive this at full throttle all the time.. but it would definitely be good to know how they hold up, so I might do an endurance test at some point.

[Krxlion]

Really great motor, and this is your first try with 3d-printing! At first, I didn't know why you put that brushless motor housing, but then it made sense, to actually have additional mounting points.
Did you need to maybe cut down the shaft length of the motor, to make sure it will fit into the planetary housing of the M motor?
I think that those planetary housing can withstand a lot, you would probably crack gear/axle first, before anything inside it breaks (speaking from own experience :D).

13 hours ago, gyenesvi said:

I am planning to make a similar motor using the SurpassHobby 2435, but of course without the back cover, but first I need to buy some M3 screws for that one. Any ideas where to get them in various sizes?

You can get them on Amazon, Aliexpress, you name it. ;) I would suggest buying conical screws. I don't know in what program you design 3d-printed case, but in Autodesk Fusion, you may design screw holes to match the angle of the screw (just make the hole slightly bigger 3.1mm or 3.2mm).

The low speed control is looking insanely good. May I ask what happens when you push the throttle (about 50% of power) and then let it go (back to 0%). Does it shut down immediately? If yes, you may need to check the settings in AM32 configurator ("Running brake level" set it to 1 for example).

It is also a really lucky situation that the pinion gear works well with M motor transmission, really lucky scenario. :D Does the gear from old motor also has 11 teeth? From XL motor it was 10 teeth If I recall correctly.

If I can see correctly, all your 3d-printed pinion holes that are in the housing are half-stud, correct?

I am looking forward to seeing a model with that motor equipped.

[gyenesvi]

4 hours ago, Krxlion said:

Really great motor, and this is your first try with 3d-printing!

Thanks! :)

4 hours ago, Krxlion said:

At first, I didn't know why you put that brushless motor housing, but then it made sense, to actually have additional mounting points.

Yes, the main reason is the additional mounting points, that's why I'd say it's optional. But also, it kind of feels better for protection as well, so that maybe wires don't get tangled up in the running motor (since it's an outrunner), in case I'd want to run wires around the motor.

4 hours ago, Krxlion said:

Did you need to maybe cut down the shaft length of the motor, to make sure it will fit into the planetary housing of the M motor?

No, I did not need to cut it, because I made the wall thick enough (4mm) so that the remaining shaft is not too long. But also, I checked that inside the planetary gearbox, the first stage carrier has a hole in the middle, and the 2mm motor shaft just fits in there, so even if it would be too long, it can protrude in there! Really useful, so that no cutting is required, which would be really difficult, and might damage the motor bearings I guess.. And the 2435 motor has the same shaft width/length!

4 hours ago, Krxlion said:

I think that those planetary housing can withstand a lot, you would probably crack gear/axle first, before anything inside it breaks (speaking from own experience :D).

That's reassuring to know!

4 hours ago, Krxlion said:

You can get them on Amazon, Aliexpress, you name it. ;) I would suggest buying conical screws. I don't know in what program you design 3d-printed case, but in Autodesk Fusion, you may design screw holes to match the angle of the screw (just make the hole slightly bigger 3.1mm or 3.2mm).

Thanks, I'll look around. Indeed, I want to buy conical ones, and also I noticed that feature in the cad designer program (I am using OnShape, and free online editor). Also, canonical screw holes have the advantage that they can be printed without support even if they are at the bottom. In fact, that's how I printed the pinholes on the front face, as that was at the bottom :)

4 hours ago, Krxlion said:

The low speed control is looking insanely good. May I ask what happens when you push the throttle (about 50% of power) and then let it go (back to 0%). Does it shut down immediately? If yes, you may need to check the settings in AM32 configurator ("Running brake level" set it to 1 for example).

Yes, it shuts down kind of abruptly. It would be nice to configure it a bit, I have the configurator board, but can only run on Windows, and I use Mac, so I need to borrow a laptop for that..

4 hours ago, Krxlion said:

It is also a really lucky situation that the pinion gear works well with M motor transmission, really lucky scenario. :D Does the gear from old motor also has 11 teeth?

Yes, and the profiles also match kind of perfectly as I put them side by side, was sooo happy about that, otherwise swapping the gear could have been a difficult step in the assembly.

4 hours ago, Krxlion said:

If I can see correctly, all your 3d-printed pinion holes that are in the housing are half-stud, correct?

No, all the pinholes on the front face and side are full stud pinholes, with proper recesses at the two ends, and pins go in quite nicely, even snap in a bit (I experimented a lot with printing pinholes from both orientations). As I say above, when printing holes at the bottom, I use a 45 degree conic section inside after the initial 0.8mm recess. When printing holes on the side, I don't use support because it did not really change anything, but a trick that worked for me to get the top of a hole right is variable layer height, optimized automatically by the slicer. This way, I don't need to do any post processing of the printed parts, they just kind of good enough. All parts were printed without any support.

The holes on the back end are not half stud either, they are just inverse stud holes, so only 2 mm deep, and no recesses around the rim. This way they hold half pins quite well.

4 hours ago, Krxlion said:

I am looking forward to seeing a model with that motor equipped.

Will post as soon as I have something! :)

Edited 12 hours ago by gyenesvi

[vergogneless]

19 hours ago, gyenesvi said:

I decided it's time for me to enter the game :) So here it comes, my first brushless motor! A small one to start with.

A few days ago I bought myself a Bambu A1 Mini 3d printer, and started experimenting with making a housing for brushless motors.

Features

• Dimensions: 3x3x6 studs
• Weight: 34 gr
• Reduction: 24x down-gearing with 2-stage planetary gearbox of PF M motor
• Speed: around 1100-1200 measured RPM, but around 1500 on paper

Design

I decided I wanted to base my design on SurpassHobby 24xx motors, based on the ideas of @HorcikDesigns presented in this thread. For me, the ideal form factor is the 3x3 one, which those motors fit perfectly, and because with a planetary reduction, we can keep that form and get good amount of reduction.

So my key idea was to take apart a (3rd party) PF M motor, and take out the planetary reduction for my purposes. The PF L motors also has essentially the same reduction, but its internal housing has a bigger shape due to the L motors bulge, and so I could not use that. I went on and bought a SurpassHobby 2435 3300 kv motor. When I started looking for an ESC, I came across this super small Injora one, and since I used its brushed counterpart already, and I was satisfied with it, I decided to order one (it can handle 25 A continuous and 60 A peak current, 2-3s LiPo, has adjustable BEC output up to 3A, and is waterproof). I realized that there's an accompanying mini outrunner motor as well, they come in a combo, so I bought that as well (17x21 mm only, 2800 kv). The wiring is really plug and play, you just need a battery with an XT30 connector, and a receiver.

To my surprise, the motor comes with a 11T gear that's a perfect match to the gear inside the PF M motor, so it meshes perfectly with the planetary reduction. Furthermore, it also comes with a couple of 2M screws that I needed for the assembly, so I set out to print a housing for this one first.

The housing consists of 3 parts. First is the front face together with the planetary housing.

Second is the mounting wall.

And the third one is the back cover (it's optional, but good to have). The rear holes serve as ventilation openings, as well as they are inverse studs for mounting.

The assembly sequence is as follows. First, the wall is screwed to the motor from the inside with M2 screws that comes with the motor.

Second, the planetary reduction slides into the two horizontal slots of the wall (the planetary housing has two horizontal tabs on the back to fix it against rotation).

Third, the front face can be screwed on at the corners from the back using M2 screws.

And last, the back cover can be pushed into the slots on the wall mount from the back. It's a really tight fit, so it does not come off.

Optionally, the inverse studs on the back can be used to fix the motor or add further mounting points.

More pictures are available on my Bricksafe.

 

I haven't yet built it into any model, only tested the bare motor. The control is insane, it has super slow startup, it can go as slow as about 1 revolution per 25 seconds, but with enough power that I could not stop it with my hand.. And then it can go up to 1200 RPM. I'm really curious how it will perform in a model :)

 

I am planning to make a similar motor using the SurpassHobby 2435, but of course without the back cover, but first I need to buy some M3 screws for that one. Any ideas where to get them in various sizes?

Awesome! Well done 

I’m jealous! Really can’t wait to see it in action