DIY spindle design

[Art99]

Hi All

I'm a newbie with a 7x10 lathe that I'm very slowly outfitting and converting to CNC. I am planning on building a tool post spindle to enable me to easily cut key-ways on shafts in my lathe. This thread has been a fantastic eye-opener.

I have purchased a 200KV outrunner motor with an 8mm shaft. It has a power rating of 2450 watts. IS THIS REAL?? At 50% efficiency this would be over 1 HORSEPOWER for a motor that I could hold in my hand.

Indeed if it is real, it is more powerful than the motor which drives my lathe!!

Puzzled,

Art99

You can get 10mm straight shaft ER chucks here.
Results for Tool & Work Holding:ER Collet Chucks
Very cheap tools to be had here.
All (3) the electronic brush-less motor driver testers I have used startup in the midband when first plugged in. I have never found a site or a way to control these things where you can have them start at zero volts and then get ramped up from there using a computer.
Mind you, it's been 4 years since I looked so there may be stuff out there that I don't know about. :-)
It would be good if someone had a way of doing this.
There are sites out there that show you how to make your own outrunner motor but the ones I have found are in German or Swedish and Google translator or babelfish don't do a very good job of converting technical lingo.
You could make your own for whatever revs you need for your power supply. That would be nice for a small machine.

If you do make your own spindles for your outrunner motors then you could use the round tool steel blanks from the same site here.
HSS TOOL BIT - ROUND STOCK - LENGTH 100MM (5 PCS) #H28
Lots of different sizes to choose from.
The hardness/brittleness shouldn't be a problem for the power of these small motors.

[Jonathan]

I have purchased a 200KV outrunner motor with an 8mm shaft. It has a power rating of 2450 watts. IS THIS REAL?? At 50% efficiency this would be over 1 HORSEPOWER for a motor that I could hold in my hand.

You can expect much better than 50% efficiency from this type of motor - more like 80-90%
At best it's the peak power rating, but how they define peak power is anyone's guess. Take it with a pinch of salt - I just go by the mass of the motor and dimensions of the stator. Bear in mind in their intended application these motors have a big propeller on the front blowing plenty of air through them which is clearly going to allow higher power than in our application which has barely any cooling by comparison. Ultimately the power rating is just a thermal limit, so if you can cool it well then you can get more power without the insulation breaking down prematurely. Either way it's plenty for what you need so I wouldn't worry too much...

[asbo]

Hi

Would anyone be able to make/sell me one of these spindles? If so how much would it cost?

Thanks.

[Jonathan]

Would anyone be able to make/sell me one of these spindles? If so how much would it cost?

I should think so...what specification do you require, or what materials and size tools do you need to use with it?

[asbo]

For fairly light usage cutting plastic, aluminium and maybe MDF. Also possibly wood. Probably 6mm flute bits max.
Would a spindle like the ones in this thread be suitable for that?

Thanks for the quick response.