Fingers crossed it'll cut ally

[blackburn mark]

cheers routercnc

will i be ok using the 80A speed controller on a much smaller motor... it would be nice if i could use all three motors without having to swap about with diffrent ESC's

im not sure ill bother linking my spindle to the PC, iv got an optical rev-counter, i think ill just dail in whatever speed i want and stick with the simple life

im considering a goverer speed controller.. iv heard they will hold the revs steady under diffrent loads

[Jonathan]

cheers routercnc

will i be ok using the 80A speed controller on a much smaller motor... it would be nice if i could use all three motors without having to swap about with different ESC's

Yes, any motor up to 80A should be fine with that speed controller. Is the speed controller programmable? You may find that adjusting some settings (such as 'timing' and 'frequency') will make the ESC run different motors more efficiently.

im not sure ill bother linking my spindle to the PC, iv got an optical rev-counter, I think ill just dial in whatever speed I want and stick with the simple life

I wonder if mach3 can do this. The input to the speed controller is just a simple PWM signal and mach3 can output PWM for spindle control at a set frequency.

I've got a huge 130kv brushless motor I think I might try as a spindle when I've bought an ESC for it. It's rated for 48v and claims to be 6500W(!) ... hadn't thought of controlling the speed from the computer though.

I agree about using a fan - these motors do get hot even running with no load from my experience. If you've got a lathe then you could make a pretty nice heatsink just by starting with a bar, bore it to fit the motor and add fins using the parting tool...

[blackburn mark]

nice one jonathan, yea iv programmed the ESC for soft start, 14 poles etc.

iv run both large motors for 5mins 12v no load without to much heat in the ESC or the motors
i exspected way more... we'll find out eventualy what they do under load

the huge 130kv brushless motor you have (if its the one im thinking it is) has a 12mm
shaft wich is good news as far as A/C bearings are concerned and if you have a butchers on ebay you should be able to find an ER11 C12 L100 straight collet shaft,, that should drop straight in:naughty:
cheak how much shaft you need though as these have only 100mm of shaft!

[Jonathan]

Yes it's the motor you're thinking of! It's currently in pieces since I'm altering the wiring so that I can change it between star/delta for higher torque/rpm etc. You may mant to consider this for your motors? Easier to swap a few wires than change the motor, perhaps.
I've found the straight collet holder - that looks ideal (thanks!), except the shaft is a bit short! I'd prefer ER25 though since I've just bought a set of ER25 collets for my milling machine. I'll have a look around for one / make one if necessary.

The bearings in the motor are already pretty huge. The one at the 'back' is a large thin section bearing about 65mm diameter if I recall correctly.

Maybe create a thread about using these motors?

[blackburn mark]

jonathan... good luck with the ER25, iv seen a few of these ER straight shafts with 150mm to play with,,
cant remember seeing an ER25 though
if you get chatter i would consider at least a double row A/C bearing at the sharp end,
they are already pre loaded and ready to go

[z3t4]

Maybe create a thread about using these motors?

Yes please!

There was an article in MEW (Feb 2008 issue, No 135 ) about making outrunner motors but there wasn't much about how to power them. I'm guessing that the 'servo tester' provides a PWM pulsetrain and the speed controller (is this aka an 'ESC'?) sees the pulsetrain and uses electromagick to provide a 3-phase supply to the motor.

John

[blackburn mark]

[QUOTE=z3t4;14653]Yes please!

it will be a while before i can report any findings on mine... i cant wait to see how jonathan gets on with that monster motor of his and what he gets with the "star/delta" wiring (i have no idea what that is and im just about burnt out on research)