View Full Version : My Mill Drill Conversion project


George
07-12-2005, 01:02 PM
I would like to start on my Mill Drill conversion. 3 axis X,Y,Z

The mill drill is very much like the bench mounted Harbour Freight that I see bein used in these threads. Mine is and Eagle25

Any help at all on drawing etc pictures etc would be vey helpful,

I started by buying a 3 axis stepper controller and 3 servo's Nema 23 size 1.7v at 4.7A these are 0.4Ohm and 200S/R 6 wires. I think I would like to go down the route of Servo's instead of steppers so I may trade my controller and steppers in.

I would like some advice on pro's n con's stepper/servo. My understanding is that the servo aproach is more reliable.

Can anyone advise please, and a size and a source of servo's at a reasonable price.

Many thanks

George

Bubba
07-12-2005, 03:01 PM
George,
I used servos on my mill/drill (RF31) and the last set is rated at 48V 1000 rpm and the first set was 110V 6500 rpm. I changed so I could have
1) MORE power
2) utilize the power of the motors within their voltage rating (geckos are limited to an actual about 70V power supply)
Now having said that, I like the servos as they are smoothm but it took some doing to get there. You will need encoders (steppers don't) and of course this entails more wiring.

Plan your system out. Get your servos first (and make sure the drivers you select will handle the required voltage) See item 2 above
Figure out what resolution encoders you will need if they don't come with the motor and how you will mount them! (Mine are mounted on the ball screws which would allow me to change the pulley sizes on the reduction unit without changing my setup parameters)
THEN after you have your servos and drives, worry about the power supply!

As to the source, I scrounged all the "surplus" sites I could find on the internet and that is where I found mine. The last ones are about 4" dia 6" long and weigh about 11@ ea!

If you want some additional info, let me know.

George
07-12-2005, 04:20 PM
Thanks a bunch.

That sounds like good sound advice.

I'll start and try to locate some servo's and encoderws.

Cheers

Goerge....

sidecar82
11-19-2005, 12:02 AM
hello
I used Geckos too cost more and need encoders
timing belts and pullies easer than direct drive more cost again
as have to buy 2 pullies and a belt for each axis bur dont have aliment problems
as with direct drive
3/4 inch roton ball screw over size balls in nut instead of 2 nuts with a spring
in between the nuts have .002 thousands back lash
stepper motors need that load resistor and you have to calculate what size
to use and it gets Hot too gecos rule

WayneHill
11-19-2005, 12:18 AM
sidecar82 - Hi from down the road in Jackson :)