I'm in the proces of choosing a set of steppers to use on my Vixen New Polaris GoTo project.
I bet the save choice is this one:
http://www.omc-stepperonline.com/nema-17-bipolar-stepper-12v-04a-40ncm567ozin-17hs150404s-p-14.htmlFor me it is a good combination of torque en weight. But the thing is that when I buy two steppers the shipping costs more than double the price, so I´ve been looking at ebay as well.
On ebay I see lots of nema 17 stappers, but most steppers with lot of torque use more than the 1,25A the DRV8825 can handle whitout heatsink.
Alternative one:
http://www.ebay.nl/itm/221420132370Alternative two:
http://www.ebay.nl/itm/281633378754The first is, for two stepper only slightly cheaper that a set from omc-stepperonline, but it's torque is also much less.
The second is much cheaper, has enough torque, but it is rated at 4,2V and the current per phase is 1,2A. When I use the stepper at 12V, can the AstroEQ controller handle the required amps and will the torque remain enough?
Until now I've been looking for a stepper with at least 360Nm torque. I imaginge that will be enough for my Vixen NP, probably more than enough, but I'm uncertain until how far I can drop the torque before it is to low.
Who can help me choose the right stepper?