Need alittle help with motor rating

[CNC Darren]

hi all,
I have a bunch of these motors http://www.nisca.co.jp/motor_eng/dc_nc5475.html
and would like to know what the oz/in rating is but i'm not sure how to convert the listed rating to oz/in. I am planning on using these on a smaller table, probably around 24x48 and want to make sure they will be strong enough. I do have several so could I use more than one motor on each axis and connect them with a timing belt drive? Not sure how i would mount the encoder then tho as it would only be on one motor. I'm new to servos and am looking at rutex for the controler.

CNC Darren

[wile_e]

hi all,
I have a bunch of these motors http://www.nisca.co.jp/motor_eng/dc_nc5475.html
and would like to know what the oz/in rating is but i'm not sure how to convert the listed rating to oz/in. I am planning on using these on a smaller table, probably around 24x48 and want to make sure they will be strong enough. I do have several so could I use more than one motor on each axis and connect them with a timing belt drive? Not sure how i would mount the encoder then tho as it would only be on one motor. I'm new to servos and am looking at rutex for the controler.

CNC Darren

1 oz = 0.0283 kg

F = m*a
g = 9.81 m/s2

1 oz ~ 9.81*0.283 = 0.278 N

1 in = 0.0254 m

1 oz*in = 0.278 * 0.0254 = 0.00681 N*m

http://www.cnczone.com/forums/newrep...reply&p=59604#
cheers

Why can´t Americans learn to use SI units like the rest of the world? http://www.cnczone.com/forums/newrep...reply&p=59604#
Roll Eyes (Sarcastic)


http://www.cnczone.com/forums/newrep...reply&p=59604#
Smilie

[wile_e]

Sorry, but my ironic but well intended smileys did not come out the way I thought they would... :-(

[Al_The_Man]

One mNewton = .001 Newtons. To convert Newton-metres to ounce-inches multiply x 141.612.
So if motor is 147mN/m .147x141.612 = 20.8 oz-inch.
Does that look right?
Also you would be better off looking for the right size single motor rather than trying to parallel servo motors.
Al

[whiteriver]

I think i attached a image. This motor says trq (stall) at 6Nm. Thats really not much if i figured right.53.1045 in/lbs. 850 oz/in i think. For such a big motor it sure don't push much. Do servos do more with less than steppers? My steppers on my router are 2600+ oz/in and the motors are allot smaller than these 3 phase servos.

Donny

www.whiterivermfg.com

[arvidb]

Servos keep their rated torque up to nominal speed, while steppers drop off in torque with increased speed.

Arvid

[Swede]

Download CONVERT.EXE and all these pesky math issues will vanish. Look in the download section of the Zone!

N*M to Oz/In no probs!

[arvidb]

Oz/In, 147mN/m

Torque is force times distance, not force per distance.

Think about opening a door: if you pushed directly on the hinges instead of the handles, and if torque were force per distance, the resulting torque would be infinite (distance = 0) and the door would smash open in an infinitely short amount of time - not exactly the way you would expect a door to behave when you touch its hinges.

Arvid

[Swede]

That's why I let my computer do that kind of stuff!