View Full Version : In need of 15k rpm motor

07-13-2015, 11:06 AM
I'm making a small test setup at the office where I need to run a small shaft at 15000rpm for several hundred hours. I'd prefer a direct connection without a belt.
What I came up with is not very satisfactory yet:
- Maxon motors, very low torque at this speed range (but might be just enough), very pricey
- brushless RC motors, cheap, limited specs available, would the bearings live long enough?
- dremel style tool, bearings and brushes might wear out
- router, bearings and brushes might wear out

I tried navigating the site of Parker, but their website is horrible if you don't know exactly what you need.

Does anyone have some other ideas where one could find motors like this?


07-13-2015, 11:20 AM
It's hard to find a good but cheap high speed motor ;)

Would one of these work? You can get some with an integrated speed controller so it is as easy as "plug and play". I'm using a 12k rpm motor with speed controller from these guys for a project at work. It's been very reliable so far...


(Incidentally, we also use Maxon motors for some applications. There is a reason why they are so pricey but they're probably overkill for a test setup)

07-13-2015, 11:29 AM
Check out brushless DC motors and controllers for RC airplanes. They are very powerful and should do what you need.


07-13-2015, 11:54 AM
The brushless motors for planes would be great if the shops selling them would indicate more than only the kV value and the weight....it's been quite the frustration trying to find figures for maximum speed or life.


Ian B
07-13-2015, 12:40 PM
how about high speed brushlesss router spindles? These run up to 24k rpm, variable speed, various powers are available: http://www.ebay.co.uk/itm/air-cooling-800w-CNC-spindle-motor-and-matching-inverter-vfd-3d-printer-router-/161240553806?pt=LH_DefaultDomain_3&hash=item258aaf994e


07-13-2015, 12:48 PM
Hmm, that doesn't look bad at all. And quite useful when it ends up in the skip at the next cleanup ;)


Forrest Addy
07-13-2015, 12:50 PM
The brushless motors for planes would be great if the shops selling them would indicate more than only the kV value and the weight....it's been quite the frustration trying to find figures for maximum speed or life.


I agree. I did a little research on brushless motor intended for RC applications where the most essential conferrable seems to be "awesomeness." They seem to be a good choice for high power density applications provided some basic specs could be extracted from the gear head marketers. I suggest you knock heads in what passes for engineering support people of KDE Direct regarding their XF line of brushless motors. The motors seem well built and their designers have a handle on the technology but speed torque curves, closed loop feedback options, control features, etc, are very thin on the ground.

I think these motors are an untapped resource for compact mechanism and it's a crying shame they aren't properly specced for industry.

Look here:


I regret this link may lead to a long profitless slog through a witless inquiry tree intended for RC trolls living in their parent's basement: "What plane is it for..." but persevere. Surely in the desert of RC-centric world of KBE Direct and peers are real engineers cranking out the designs. I bet they are starved for intelligent technical dialog.

07-13-2015, 01:25 PM
The high end routers and spindles such as Kress etc, have precision low run out bearings and typically run for hours a day for many years in CNC applications without need for brush replacement.

07-13-2015, 01:45 PM
Also Fischer Precise (formally precise) makes a lot of high speed spindles with ABEC 9 bearings. Some are air/oil mist lubed.

There are also some air bearing spindles on eBay, I think made by Dover. They might go fast enough.

07-13-2015, 11:57 PM
Dumore tool post grinder and precision drill press motors go up that high and use quality bearings. They are frequently on the bay. Here is a 17,000 rpm version. Dennis


07-28-2015, 08:39 AM
To come back on the thread, I purchased a complete asynchronous spindle instead of only a motor:


In the end it was as expensive as getting a Maxon motor, except now I have a 2kW spindle instead of just a 100W motor. It's rather heavy though at 17lbs....
The benefit of having a rigid spindle like this is that it makes the rest of my setup much simpler, saving me on other parts etc.
Thanks to all who gave their thoughts.


Forrest Addy
07-28-2015, 10:40 AM
That is indeed a killer solution.