Torque of stepper motor

I have one of these http://www.sparkfun.com/commerce/product_info.php?products_id=9238 connected to this http://www.sparkfun.com/commerce/product_info.php?products_id=9402
.

Does anyone know where I can get stronger stepper motors than those ones. (preferably same type, bipolar, that way i dont need to change my driver card)

At the moment I can hold them with my fingers, I need at least twice as strong? I tried running them on 32 volt, but that didnt give them any more torque. Or is the problem with driver card?

Kim

The stepper is rated at 330mA (pr phase ???) and the easydriver board can deliver 750mA so i guess the motor is the week point.

Have you tried to adjust the small current adjust trimmer pot on the easydriver board so it gives more current ?

It’s a good idea to use a amp meter to meassure how much current goes to the motor to make sure you get around the 330mA the motor needs to do it’s best.

I tried running them on 32 volt, but that didnt give them any more torque. Or is the problem with driver card?

32v? lol hope that’s a typo, the motor board’s “max” is 30 volts, while the stepper motors themselves are 12v “max”.

Just wanted to point that out, just incase it’s not a typo.

But as for the extra torque, I have no experience with stepper motors personally, but you might find some servos that could do the trick for you. (I know they’re not for the driver card, but you can control them from a single pin each)

what about this one?
http://www.probotix.com/stepper_motor_drivers/SideStep/ together with
http://www.probotix.com/stepper_motors/ht23-260-4/

or is there cheaper options out there?

http://www.hobbycnc.com/products/hobbycnc-pro-driver-board-packages/

Is this a good buy and can it be interfaced with arduino?

Cheers Kim

If you only want two times as much torque, can you sacrifice some speed and fit a reduction gear on the output of the existing motors?

It’s supposed to be connected to a PC parallel port, but since all the parallel port is used for is setting some pins high/low, i guess you could do that with Arduino.

Depending on your purpose this package might be over kill.

Well, i need stepper motors with more than 200ozin in torque and some driver to drive them. If you know about a cheaper kit please let me know. I found stepper motors for around 40USD which means 4*40 + shipping is around 200usd. And then I had problems with finding driver cards, found some to around 100usd+ shipping. I figured out that 335+shipping(60usd) might be a good option for 4 stepper motors with 305ozin in torque.

But if u know about a cheaper packet please let me know.

Do the paralell port support 5volt logic?

found this set on ebay:
http://cgi.ebay.com/CNC-Mill-5-Axis-Control-Kit-NEMA23-Stepper-Motor-Driver_W0QQitemZ180451260924QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2a03bbb9fc
might be an even better kit or?

Yes the parallel port pins are 5V for high and 0V for lov.

There are 8 data pins + a handful of signalling pins.

I bought a set of these http://tinyurl.com/yeatkks a while ago for a cnc pcb drill. They come with a power supply and an interface board. The shipping charges are a bit expensive though. The performance is impressive, I managed to get a motor doing 1800 rpm using an arduino.
The fastest stepper motor I have ever used.

If torque is the main issue, then you should maybe look into some gearing of the motors ?

Well, already did some research on that, looking for planet gear boxes for rc motors. However i found out that it probably is better to just get some stronger stepper motors. I am trying to make a cnc mill for wood, so hopefully 200 ozin should be strong enough for this purpose

If a CNC is your goal then i would go for one of the packages with motors + controller / driver for them.

That way you get something that is well matched from the start.

Hobby CNC seems to have a good reputation in DIY CNC circles.

http://cgi.ebay.com/CNC-Mill-5-Axis-Control-Kit-NEMA23-Stepper-Motor-Driver_W0QQitemZ180451260924QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2a03bbb9fc
Don’t you think this is just as good kit or?

It seems like good value for the money.
Just out of interest, what are you going to drive with the motors? I have mine driving good quality ballscrews and I can turn the current output of the driver boards down to less than 1 amp and still get plenty of linear force to drive my machine.

I looks like a good deal, 5 steppers and shipping included.

The steppers looks like they are the same class as the Hobby CNC steppers, but a little stronger.