Regarding ballscrew rotation speed, they say <ballscrew diameter> x <RPM>
shouldn’t exceed 70000 and that’s about it. So with a 1605 ballscrew, 4375 RPM is my limit.
And I agree that 9mm 2MGT is almost certainly enough but I have dreams of doing crazy things to my machine like sticking on an 80mm spindle with ATC in which case I might want a bit more stiffness in my belts. I couldn’t find backlash numbers in the guide you linked though?
I’ve been looking at giant pulleys out of necessity unfortunately, that’s a big part of the problem. My servo shafts are 14mm and the only pulleys that support bores that large are enormous. But on other hand, I don’t want too large a pulley on the ballscrew because that makes designing the axis as a whole a bit more painful.
I’ve seen a lot of stuff on this forum about tension so I’m very aware of the need. My plan at the moment is to add an idler on top of a stiff spring that can be adjusted by one grub screw and locked into place with another. That should allow me to apply a reasonably precise but consistent force to the belt.
Thanks for the supplier recommendations! I’d looked at POWGE in the past but couldn’t find what I needed from them. I was looking at the 3GT section which looks pretty empty but the 2GT section is apparently pretty full! The others look good too. I like the eBay seller but the problem with most of the European sellers is that they take so long to ship that I may as well just order from China…