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View Full Version : Miniature Lathe for Pen Turning - Brushed or Brushless Motor?



Nealieboyee
28-10-2012, 12:01 AM
Hi All,
While I'm waiting to build my CNC router (Saving up for the electronics and lead screws), I thought I'd have a go at building a small desktop wood lathe for pen turning, shaping acrylic etc.

I'm stuck on the motor type to use. A 1/2hp motor is probably waaay too large for my application. Would going DC be better with regards to speed control? I'm on a really tight budget, so I can't splash out hundreds of pounds for a motor. I just need something small with enough torque.

So my questions:

1. DC or AC
2. If DC, then brushed or brushless (brushless being quite expensive)
3. What size and voltage? (No 3-phase supply so i'm limited to mains)

Your input would be very much appreciated.

Kind regards,
Neal

m_c
28-10-2012, 11:31 AM
Whatever you get cheapest?
If you design the lathe using a belt drive, you can change the motor fairly easily at a later date.


All have pros/cons.
AC should be more reliable, however unless you go for 3 phase with a VFD, you won't get speed control.

Brushless in theory should be more reliable, as there are no brushes to wear, however I wouldn't say any of the cheap brushless options will be any more reliable. Have you searched out the homebrew spindle thread using a brushless motor for some ideas?

Robin Hewitt
29-10-2012, 03:58 PM
Personally I prefer AC. A nice rubber mounted brushless AC motor with a vee belt, simply because it is practically silent. Noisy machines do not encourage fine machining. You can get tiny vee belts fairly easily, finding the pulleys is the tricky bit.

(He said, hoping someone might pop up and suggest a source for sub-Z pulleys :very_drunk: )

Nealieboyee
29-10-2012, 05:56 PM
The pulleys i can manage. Finding a small brushless ac motor is proving difficult. Any sources that you know of?

D.C.
29-10-2012, 11:34 PM
You could always try looking at robotics/model building places for this sort of thing.

Robot Motor-Motorized Window Blinds (http://www.bgmicro.com/robotmotor.aspx)
Brushless Motors List (http://www.aeromicro.com/catalog/brushless_motors_107406_products.htm)
Gears - Technobots - Electronic & Mechanical Components (http://www.technobotsonline.com/gears.html)