Hey Jim,
Thanks for the kind words here on CNCZone. Through the years, I have learned most of what I have implemented my website from all of the experts here.
I would recommend the 2 starts rod and you can source them from Mcmaster Carr. They have the 1/2"-8 2 starts which will yield 4 revolution per inch. Length are 6" or 3" which can be cut down to proper length. Don't forget the wear compensation nuts. You will reduce backlash with these nuts. I think you can also get wear compensation nuts from dumstercnc that match the mcmaster carr rods.
These compensation nuts will be flanged for easy adaptation to the kit. I will guide you if necessary.
Thanks again, Patrick
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