High power RC motor and drive unit production

[natem]

It's about as nice as you can get. Very freaking cool. I look forward to obtaining one.

One thing that you can do to possibly improve the device is add a rubber coupler from the gear to the motor. Electric motors tend to be rather jerky and while I know that this can be controlled by the brushless controller it still is probably a good idea, I suppose since shocks can go up the drive train in a different manner.

When your motor is jerking and your tire hits a rock or get caught on something, then something has to give. The rubber coupler gives that elasticity that can help deal with that.

By reducing the shocks to the drive train in that manner you can get away with making the stuff a lot more lightweight then you could otherwise do it. Also make things last longer, reduce the chance of stripping belts or gears and whatnot.

Just a idea.

 

[Miles]

That is a great idea ...cheaper to build smooth one but then you have to use AT belt instead of HTD...

Works ok with HTD/GT, for me (in testing)..

 

[GGoodrum]

It's about as nice as you can get. Very freaking cool. I look forward to obtaining one.

One thing that you can do to possibly improve the device is add a rubber coupler from the gear to the motor. Electric motors tend to be rather jerky and while I know that this can be controlled by the brushless controller it still is probably a good idea, I suppose since shocks can go up the drive train in a different manner.

When your motor is jerking and your tire hits a rock or get caught on something, then something has to give. The rubber coupler gives that elasticity that can help deal with that.

By reducing the shocks to the drive train in that manner you can get away with making the stuff a lot more lightweight then you could otherwise do it. Also make things last longer, reduce the chance of stripping belts or gears and whatnot.

Just a idea.

We used to have a similar problem with high-power RC helicopter setups. The initial torque would snap the rotor blades so hard that unless you spun the blades first, you'd strip the main gear. Since then, however, most, if not all controllers have a programmable slow ramp up feature, on startup.

-- Gary

 

[etard]

Where the HELL is CNCaddict and those sweet inrunners he was talking about? His prices seemed to br a little more reasonable than these Astro's. Will you be passing a discount along o forum members Gary?

 

[CNCAddict]

Haha, I'm working hard on this guys. I need to find some high temp epoxy and a few other little things to get the prototype going. This motor is a i8060/2y-200 and should do over 200A continuous.

 

[etard]

200 AMPS!! This thing is going to rip apart some hubs. I will gladly sacrifice my steed for the progress of the revolution. :wink: Now we need Richard and Gary to design a three way power setting module to limit the forces through the system.

I am not sure I understand why you need different epoxy than before, Inrunners seem to be an older tried and tested technology, the magnets are stationary right? Can't wait to see this thing.

 

[CNCAddict]

Haha, yeah I'm going for broke with this motor. It should be ~3x the power of the Astro. Also, this is an inrunner, so I need to use some composites to hold the magnets in place at 10-15,000rpm.

 

[liveforphysics]

Beautiful motor! Fantastic work!

 

[swbluto]

Cool motor.

I haven't been keeping up with this thread(and I don't really want to until something definitive happens.), but has David developed any suitable motors yet of any kind? I think he has, but I just want to be sure. I have a feeling I may order one of his mythical motors pretty soon, assuming it isn't as mythical as I think it is, and it'd be nice to know where to order one.

 

[1000w]

Miles and recumpence that is a brilliant idea (flat pulley).
Matt what series toothed belts are you using? Are any of the round tooth belts best?
Do you think 1500w through a 20 tooth 5mm pitch pulley driving a 250mm diameter flat pulley, (this should give me 8:1) using a 9mm wide belt will work? A 15mm wide belt may cause some clearance issues.
Anyone know where to find a 250mm flat pulley or one that I can machine flat ie a V pulley or something similar?
Cheers,
Matt.P.

 

[CNCAddict]

Haha...not sure about "suitable". I have some pretty nice RC heli motors....but sold the last one today. I'll have more of those in a few weeks. You can see what I have for sale here http://www.xeramotors.com

 

[Miles]

I have one of David's 4035 4Y motors - I can certainly vouch for the high build quality

 

[shinyballs]

Haha, I'm working hard on this guys. I need to find some high temp epoxy and a few other little things to get the prototype going. This motor is a i8060/2y-200 and should do over 200A continuous.

holy mary! with that much power(>9,000 watts), would be best to use it on a motorcycle, if not a custom ebike frame.

Matt, will your drive now work "as is" on a motorcycle, or a different drive version. Could you do a drawing/sketch showing where to mount?
btw, fantastic drive! will definitely use it for my next build...

 

[recumpence]

The only limitation of my drive that I can see is a 7kw limit on the 15mm wide 5mmm pitch belt. However, a #25 chain will always work as a primiary reduction too. So, that would put the power handling of my drive right up there with David's new motor.

I have one of his 40 series motors too. Nice!

Matt

 

[MitchJi]

Hi,

It weighs 27 ounces as you see it.

So complete units (motor, belts, FW etc.) should be under six pounds (or close). Thats great .

The drive as you see it is 4.25 inches wide. With freewheel it is about 4.5 inches wide.

It looks like it wouldn't be hard to make it 1/4" to 1/2" narrower by putting the set screws on the big pulley closer to the belt and then removing some of the shoulder. It looks like there is plenty of room to move the set screws, mostly due to the material you removed.

One thing I did notice, however, is that I think I need the output shaft to be about 3/4-1" longer, for the drive assembly to be centered on the frame and have the drive cog line up with the crank.

Merely making the shaft longer will increase the load on the shaft and increase the twisting force (longer lever) on the mount. It might be better to increase the width of the mount (or add a second mount). That would both eliminate the added load on the shaft and create a wider stronger base for mounting.

IMO D (with help from Matt, Miles and Gary) has come up with an excellent configuration. Single stage - FW in the large pulley and 219# chain to the crank. Using 219# chain to the crank results in much more reduction than would otherwise be possible with a single stage unit. Matt would you please post pictures of D's drive when its complete? If you do a side view and an end view with a ruler D can get a head start on his planning.

holy mary! with that much power(>9,000 watts), would be best to use it on a motorcycle, if not a custom ebike frame.

Hey! Stop insulting David's motor! :lol:

I think he mentioned it is designed for 70 or 80 volts which is 14kw to 16kw!! I'm pretty sure he can easily produce longer versions of the same design for even more power. On a motorcycle where space is less of a premium I think 1.5x should easily be possible.

Also the pictured motor is a little longer than ideal for Matt's Drive. So an ideal Ebike version might only be rated at 150 amps.

 

[shinyballs]

boy, your trippin again!? stop taking those pills from your momma's medicine cabinet! :lol:

I think it'll be a lot simpler to use the drive in a motorbike cause its already built for motorized use. The drive can be mounted where the original drivetrain is but a bit further back near the rear wheel. So, chain length is shorter and still maintains the stock chain alignment - wishful thinking? knows how to ride but had never worked on a motorbike.
besides for the motor, how many mounts are there in the drive?, been to lazy to read the entire thread... and how efficient is a Matt/Davids drive/motor combo in a motorcycle?

Hey! Stop insulting David's motor! :lol:

I think he mentioned it is designed for 70 or 80 volts which is 14kw to 16kw!! I'm pretty sure he can easily produce longer versions of the same design for even more power. On a motorcycle where space is less of a premium I think 1.5x should easily be possible.

Also the pictured motor is a little longer than ideal for Matt's Drive. So an ideal Ebike version might only be rated at 150 amps.

 

[recumpence]

I have had a number of inquiries into using my drive in a motorcycle application lately. Here is my thought on it;

The weak link is the primary belt. That belt is good for 5KW easily or 7kw with a 22 tooth or larger motor pulley and alot of belt tension. I recommend 5KW, though, for belt life. Now, in a motorcyle, that is not enough for most applications. However, that being said, there is no reason why a #25 chain cannot be used in my drive without any modification what-so-ever. A #25 chain will handle upwards of 20KW. There will be some chain noise, though.

Lastly, the mount clamps to the bearing tube. That mount can rotate around the bearing tube if there was truely 20KW going through it. So, the mount would have to be Loctited into to the bearing tube or pinned to handle that kind of power.

I have one customer I am setting up a drive for that will be doing just that. :wink:

Matt

 

[GGoodrum]

I got my 3210 yesterday. It is a bit bigger than I envisioned, but this is good. Here's a few shots of it, mounted on Matt's drive:

I must say, finish-wise it's a good match with Matt's "naked" drive.

Dee's motor is ready as well and I will send it off to Matt, for fitting to his drive.

More later...

-- Gary

 

[Miles]

The new squared-off case looks bulkier. Easier to mount now, though...

 

[deecanio]

looks uber cool 8)
i must say it does match up with the drive superbly, i'm almost tempted not to aodise almost but not quite, i'll just have to black up the astro
looks awesome gary, can't wait for you to setup and tell us how it performs


By the way Gary, i was looking at mounting the drive the other night and i came across these, you can see that the wheel just bolts onto the clamp so you could remove the wheel and bolt the bracket straight on matts drive base, then just clamp to the seatube? i was thinking i may use three or four of these and just clamp it on? to give the seat tube a bit more of a chance im hoping to fill the section im clamping to with solid ally bar?
just a thought........................


http://www.chainreactioncycles.com/Models.aspx?ModelID=21878

Cheers,

D

 

[Ypedal]

*squirt...

 

[deecanio]

:lol: :lol: :lol:

wooohoooooo my drive is coming too !!!!!!!!!!!!!!!!
it all can't happen quick enough :lol:

 

[swbluto]

Haha...not sure about "suitable". I have some pretty nice RC heli motors....but sold the last one today. I'll have more of those in a few weeks. You can see what I have for sale here http://www.xeramotors.com

Ok, those look sort of applicable for EVs. What kind of power do you think they could reliably sustain continuously? I'm looking for something in the 1-2 kW range and I'm not entirely sure if your ~500g motors 240kV 70mOhm motors are upto the task.

 

[GGoodrum]

*squirt...

Too funny! :lol:

By the way Gary, i was looking at mounting the drive the other night and i came across these, you can see that the wheel just bolts onto the clamp so you could remove the wheel and bolt the bracket straight on matts drive base, then just clamp to the seatube? i was thinking i may use three or four of these and just clamp it on? to give the seat tube a bit more of a chance im hoping to fill the section im clamping to with solid ally bar?
just a thought........................

Hmm... The holes in Matt's drive are on the sides, so maybe these type clamps might work turned sideways, and then a plate that bolts to these and to the mount? You'd need four of these, two for each side.

What we really need is a different mount that has a built-in frametube clamp. :wink: :wink: Got any freetime yet Matt??

-- Gary

 

[CNCAddict]

Hmmm, the 3 or 4 turn would be better for that kind of power on 50V. The small motors need high gearing to put out lots of power. Even 3-4Kw continuous is possible if the motor is spooled up to ~25,000rpm.