But honestly I'm a bit disapointed ... the extra 10Nm and extra 1.2A will NOT make a big difference!!! I think that in microstepping mode the absolute difference is smaller and therefore there is not much improvements ...

It's a bit of pitty but anyway - It's good to know that I now have the maximum I can get out of the given material!

Digi-Key is a whole saler and only selling to registered companies and the few interesting types all have a MOQ of 10 pcs!

Yes I found that out when they wanted to charge me $300 for but a set of 10 steppers and would not let me purchase 1.  I will say that the online customer services was very good though. 

http://www.digikey.com/product-search/e … ageSize=25

https://shop.stoutwind.de/Nema-17-Schri … altemoment

I've already modified the mainboard driver to give me full 2.0A to the stepper - this will require a heatsink on the driver as well. I hope to get it this weekend so I can try and report. The motor is a bit more heavy but gives much more torque due to the design and the higher current I can run with it! I've also modified the other stepper drivers so they will run the motors with 1.0A not just 0.825A as in stock version. I think / hope this will compensate the extra weight!

Here is the datasheet from the supplier of the stock motor: http://www.eminebea.com/en/product/rota … pm-k.shtml

Holding torque of 380 mNm that is 38.0 Ncm!

According to the datasheet the maximum current is 1A - when you replace the stepper with a different model you should select a type with equal or higher current ratings. The drivers on the board limit the current to about 0.825A anyway - so you will not damage the board! Please refer to this thread for more information about the stepper drivers!

http://www.soliforum.com/topic/11346/st … rs/page/2/

Checkout http://www.soliforum.com/topic/14628/ex … 17pmk142b/

Thanks Viper, I am familiar with the thread.  I suppose I was seeking a broader understanding of the ins/outs of steppers on the DaVinci and perhaps my post was not very clear.  I essentially want to know what are the technical parameters of using steppers for the extruder on the DaVinci.  As I indicated I know that it needs to be 1.8 and NEMA 17 compatible.  I would like to know if amps, volts, shaft size, etc matter. 

I was also seeking a recommendation for a larger version of the stepper as well, similar to stock.

I am entertaining options for a replacement extruder stepper motor.  I will be doing some upgrades and prefer to keep my stock one intact with the gear on there.  My understanding is it needs to be NEMA 17 compatible and 1.8 steps.  How important is the amps?  They seem to vary by a lot and I believe the DaVinci one is either .9 or 1 amp.  I don't want to get one that will be too demanding for my board.

I will most likely be getting two of them.  One will be a smaller pancake motor that Viper has referenced in another thread. 

http://www.amazon.com/Short-Bipolar-Mot … ge_o04_s00

That is now out of stock. 

Another will be a similar sized one to the stock one.  I am trying to find one that will have the correct stats for the DaVinci and the same way to attach the wiring harness (although I could live with something else).  Does anyone have any recommendations on a "drop-in" replacement for the 1.0a ?

Something like this one??

http://www.amazon.com/Stepper-Motor-Bip … ds=Nema+17

I realize that the wiring for the DaVinci's is different but that is another topic. 

Thanks