Motor size

[Philmollatt]

What size stepper motors would drive a series I bridgeport x, y, axis and knee, or motor/pulley size variants. Ive had a look around the net and it seems servos would be better but just cant afford them,
Also has anyone here done a bridgeport conversion?
Thanks

[graffian]

I got a stepper motor off an old matchmaker mill, it was in my local scrapyard. The motors were
10A size 42 motors, the one I took powered the x-axis direct drive. I would guess your needs are
pretty similar; you might well find modern 34 motors are as powerful as old 42's?

[Gary]

I have supplied a number of people converting mills of this size, and allways went for the SY85STH156 with either the PM980 or PM2278.
Most converted the quill, not the knee though.

[Philmollatt]

Thanks for the replies
Ive looked at the motors and drivers on the zapp site they look like they will do the job, i will still be doing the knee rather than the quill, but with reduction set up with pulleys. Ill have to save up a bit though 3 motors and 3 controllers will be pushing my budget a bit (along with brackets, plugs, sockets, wiring, enclosure box, etc). This hobby can get expensive very quick.
Also can i drive the PM2278 from a 220v three phase supply from an inverter

[Gary]

The 220V is the max voltage and single phase is 230 but can peak up to 280V.
I suggest using an isolating transforma giving a max voltage of 110V.

Thanks for the replies
Ive looked at the motors and drivers on the zapp site they look like they will do the job, i will still be doing the knee rather than the quill, but with reduction set up with pulleys. Ill have to save up a bit though 3 motors and 3 controllers will be pushing my budget a bit (along with brackets, plugs, sockets, wiring, enclosure box, etc). This hobby can get expensive very quick.
Also can i drive the PM2278 from a 220v three phase supply from an inverter

[Robin Hewitt]

The 220V is the max voltage and single phase is 230 but can peak up to 280V.
I suggest using an isolating transforma giving a max voltage of 110V.

It says 175VAC in your advert.

My knowlege of transformers is slight, but I do seem to remember they are wonderfully isolating, so it should be possible to wire several transformers in series so long as the windings can handle the extra current. (unless you can find a supplier for 175VAC kit).

Also, Amps :nope: 7.8 Amps at 175VAC is 1.3kW. Obviously you don't need transformers rated for that, the motor would melt. So how many VA do you actually need from the transformer to drive this beasty?

[m.marino]

Being that I grew up with 110 just remember that crap will grab and hold you if you get caught by it. Be very careful with 110; as I personally know of more than one person who has had near death experience at it's kind touch. One of the nice things about 230 is that it does tend to throw you more than grab hold and burn through you.

Michael