Dyson Digital Motor (Vacuum Cleaners)

[Gary]

What speed and torque are you after?
the fastest we offer has a no load speed of 43000 rpm.
I have seen small motors run faster, but they were induction motors specially made for drilling applications like dental drills, but they can be expensive.
These were made by http://www.airbearings.co.uk and they can offer speeds of up to 300000 RPM.
but at these speeds expect to pay a lot and will also use air bearings

All good stuff but it is speed I am looking at. A Dremel tops out at 33,000 rpm, no load, and I consider that a little pedestrian.
Ok so gear things up but using something like belt drives at high rpm involves tensioners and even then at high speeds perceived internet wisdom seems to think that belts stretch, slip, burn out, skip out of grooves, become unbalanced, 'become complicated'. Gears seem to suffer a similar perceived status of 'complicated'. At the moment my thinking is that direct drive is the way to go but I am still very much open to persuasion and/or reasoned argument

[templecorran]

Having started to look at bearings for high speed operations it looks like your burn out after a 100 hours may well be 'par for the course'. I looked at angular contact bearings with rated speeds of up to 200,000 rpm (phew!) and when you take into account preloading and cooling and lubricants and distortion of the shells due to centrifugal force, blah, blah, blah then 100 hours is 'par for the course'. Anyway back to the Dyson motor. If it contains bearings that will stand up to a 100 hours usage (which lets face it, for say a years warranty is ball park reasonable to expect) then maybe the motor is worth consideration.

Excuse me, My point had to do with the expected life of the motor under the conditions it was designed to be used in, verses the life expectancy of the application to which is suggested in this thread. In practice the component that fails is the bearing at the business end of the motor.

I modified the base of a B&Q 1020W router (£25) for use as my RockCliff spindle. After more than 100 hours of use, my router ground to a halt with a failed bearing. I was somewhat surprised when looking for a replacement that the 6003ZZ bearings are typically rated for 22000 RPM in grease and 28000 in oil. The max speed for the router is 34000!.

I've attached the 3d dxf of the modified base for your amusement. Please don't ask for g code. My final design removed material around the base to lighten it considerably.

I better stop here -- this is getting waay off topic!