Re: Brushless Motor Spindle with CNC desktop machine

The problem with these types if motors is that they were not
designed to take the side loads we apply in a milling situation. I
would not expect them to last long unless you were milling something
very soft, at very slow feed speeds.

Ron

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "baccus61" <richmcm@a...>
wrote:

> hey everyone,
> I am building a small desktop 3D milling machine and needed a
> brushless motor for the main spindle. I got sick up and fed of
> changing brushes on the prototype I built, and a brushless motor

will

> also be much quieter for indoor use and last a whole lot longer.
> I purchased a model aeroplane motor - AXi 2826/10 motor (rotating
> outer housing for better torque and the rotor doesn't throw off

it's

> windings) with an "easy 25" 25amp controller and I need to know how
> the controller signals are sent from the RF module to the controler
> and the type of pulses. In the "easy 25" instructions it lists
> positive pulses at 1.5 ms with a period of 10 - 30 ms. What voltage
> would these be. "3v - 5v"? and are they continuous pulses. If this

is

> the case then I think it would (maybe)be a case of programming the
> software to use the 4th axis as the speed controller and inputing

the

> appropriate commands into the G-Code
> These motors spin around the 10K-20K revs at 12V(and faster) and

pull

> up to 40 amps so the power is there for a small Miller but I am not
> sure how they would react to a filtered DC power supply with the

BEC

> (Battery Economiser Circuit).
> The best case scenario would be to just have a switch to turn the
> thing on and off and if anyone out there has a way of doing this
> (small circuit board with a pulse module?) then that would be

great if

> they could contact me about doing this or better still post here.
> If anyone else has any ideas Idea about controlling a brushless

motor

> with a CNC spindle then I will be forever, eternally greatful if

you

> could let me know how you can do this.
> I haven't found anyone else doing this sort of thing with radio
> controlled stuff on CNC machines so maybe this will be a first and

if

> it works the we can tell all the other CNC people out there how to

do

> it and I know they will be greatful as brushed motors just aren't
> cutting it when it comes to running a CNC/engraving job for 9

hours at

> a time. The brushes wear out after a very short period of time and
> usually halfway through a job and I know you can all sympathise

with this.

> Please help.
> Warm regards
> Richard.