Would it be worth the extra weight to upgrade the X motor to a higher torque model?  How about if you want to go to dual direct drive extruders?  The stock model is 180 grams and had a holding torque of 19 oz-in.  Here is a model that has 56.7 oz-in holding torque but weighs 290 grams.  Worth it?

http://www.omc-stepperonline.com/nema-1 … -p-59.html

The NEMA 17s and 14s have different bolt patterns, so you can't just use the same motor for all axis, although you could make an adapter plate easy enough if you really wanted to.

Would you agree that the motors I linked to are good replacements for the stock solidoodle motors?  There were a lot of choices on that site.

There is reduced torque between microsteps, but it does not reduce the full step torque (which is what must be overcome to miss a step).

You cannot lose a microstep, it is not physically possible. You can fail to move on a microstep, but it is not lost. It will be added to the rotation that occurs on the next step (micro or full) that successfully moves the motor.

mdr: 1/16+0.9deg is better IF the 0.9deg motors have as much more more torque than the 1.8deg motors. The reason is that microstep torque is reduced with increasing microstep divisions. If micro stepping a 1/32 driver, the first microstep (1/32) has less torque than a 1/16th microstep. However, the SECOND microstep (2/32) has the same torque as a 1/16 driver.

http://www.micromo.com/microstepping-my … -realities

More powerful 0.9 degree steppers would allow you to gain more steps with less microstepping, which ultimately means more torque. So yes, it is advantageous. I have a 60 oz-in 0.9 stepper I will be installing on my Y axis soon.

I don't know how low steps per mm can go on X/Y/Z before the steps become apparent in the prints, but the more steps, the better, if you're not sacrificing torque.

So are you saying that 0.9 degree motors with 1/16th microstepping is better than 1.8 degree motors with 1/32 microstepping?  If so, why?  Both configurations come out to the same 160 steps/mm (using GT2 belts, 20 tooth pulleys) so I would have thought it is a wash.  I'm just trying to understand.

Of course, you could go all out with 0.9 motors and 1/32 micro stepping for 320 steps/mm but I'm just not convinced you would ever see a visible difference.  Even with an extremely well calibrated machine that is a tiny distance.

Ya I would be pretty happy if someone more knowledgeable than me chimed in here but here are a few that seem similar in volts, amps, holding torque, etc to the stock models from the above post:

Similar to X motor:
http://www.omc-stepperonline.com/nema-1 … -p-91.html

Similar to Y motor:
http://www.omc-stepperonline.com/3d-pri … -p-17.html

Several more robust models are available at the same website.  I wonder if there is any benefit to upgrading to 0.9 degree motors?  Yes, you would double the steps/mm and therefore the resolution if I am thinking correctly but at a certain point you are running into moving the nozzle to a greater precision than you can really control the plastic flow (if that makes sense).

More powerful 0.9 degree steppers would allow you to gain more steps with less microstepping, which ultimately means more torque. So yes, it is advantageous. I have a 60 oz-in 0.9 stepper I will be installing on my Y axis soon.

I don't know how low steps per mm can go on X/Y/Z before the steps become apparent in the prints, but the more steps, the better, if you're not sacrificing torque.

Similar to X motor:
http://www.omc-stepperonline.com/nema-1 … -p-91.html

Similar to Y motor:
http://www.omc-stepperonline.com/3d-pri … -p-17.html

Several more robust models are available at the same website.  I wonder if there is any benefit to upgrading to 0.9 degree motors?  Yes, you would double the steps/mm and therefore the resolution if I am thinking correctly but at a certain point you are running into moving the nozzle to a greater precision than you can really control the plastic flow (if that makes sense).

http://www.smartautomation.com.cn/Produ … icleID=500
http://www.smartautomation.com.cn/Produ … icleID=497

http://i.imgur.com/eYTRvPY.jpg
http://i.imgur.com/BS7ImKz.jpg
http://i.imgur.com/OibV0mm.jpg

Now I guess the question is,
if the main variables are
torque,
Amperes

Should I look for a motor with the same torque or Amperage? Or is more okay? Or do I risk damaging my motherboard?

what are those specifications of stock Solidoodle 4?

That would be the key wouldn,t it. I see no specs on there web page.

But there seem to be so many variables besides the size. Which should I pay attention

Of course the frame size this is the NEMA 14,17, 23 etc.
then the length of the motor.
torque spec in newton meters or oz/inches  iirc this number ranges from about 76 oz/in  to 89 oz in for the NEMA 17 i have looked at for 3d printing. and the amp rating is something to look at.

I suggest you get a spec sheet and llok at before you buy  a motor.
There are lots of tutorials on stepper motors . You may want to look at the reprap wiki.
and there is some discussion here.

http://www.soliforum.com/topic/7893/sou … ma-motors/
Tin