I'm looking at places such as McMaster Carr for acme threaded rod. Price isn't too bad. But they sell so many different types, sizes, fits, etc. I'm building a very light duty (12"x12" deck) CNC for engraving purposes. What is it I exactly need to do this? I'm looking at having my steppers run though a reduction gear to gain torque, so how would I fix the gear directly to the rod? Any good means of attaching the head to the rod? I'm completely new at this, so not sure what i need. Anyone able to help out a fellow DIY'er?

Go to dumpstercnc.com to find the anti backlash nuts for what ever acme thread you plan to use, you would want to attach the AB nuts to the gantry or table (which ever is going to be moving) and the z axis.

I use acme 1/2-8 2 start thread with dumpster AB nuts.

Another place to find more info is cnczone.com

Do you have a sketch of what you are trying to do i can sugest how to attach motors as well as mech. to list table.

Joe