Stepper Motors

Hello guys!! FIrst, thanks for all the information you have provided trough this forum. Sorry if this is somewhere here, I couldnt find it.
Im gonna buy some stepper motors from tony34306 on ebay and dont know what is best. Im gathering the parts to build a graber i3. These are my two options:

[www.ebay.com]
[www.ebay.com]

I know that the second option is gonna work just fine, but i want to know if the first, by having a greater torque and the same current of 1.2A, is gonna be better, cause any trouble or be overkill. Thanks again!!

The first option looks OK to me. The only question I have is how many teeth the pulley have. 16 or 20 is good but you don't really want more than that.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I'm using these:
[www.ebay.com]
in my Prusa i3v. Essentially the same as your first link, but in a package of 5 and without preinstalled pulleys. They work just fine. I use 0.8A, which I found to be the perfect balance between torque and heat dissipation. Datasheet at [www.eminebea.com]
The exact model number is 17PM-K402-P4V, and they're practically identical to the ones listed as 17PM-K442B in the datasheet. Or 17PM-K442U if you use in unipolar. Note that for bipolar drive, they're rated only up to 0.9A (the 1.2A is for unipolar); indeed I have found that if you increase the current over 1A in bipolar, they tend to stick and skip.

Edited 2 time(s). Last edit at 11/21/2015 07:43AM by stamasd.

Many thanks for you both
I was going to buy one kit from another top seller but discovered after some messages that the motors shaft had 4mm diameter. Must be careful with that... I thought that all nema 17 had 5mm shaft. Here in Brazil at least im pretty sure i would have some trouble finding a pulley for these. And I ended up buying the same kit stamasd! Cant wait to get them Also thanks for the additional info on the motors!

You're welcome. I generally print my own pulleys, but if you don't have access to a printer while building one it leads to a problem of the-chicken-or-the-egg unfortunately.

Good luck with your build. Actually, since I like to have many spares I just ordered another set myself.