Question: What would be the preferred timing belt for a new design? Here is the application. I'm making a z-axis control for a Harbor Freight mini mill (Sieg X2). In this design a 5/8 diameter, 0.200 pitch ball screw is fixed and the nut spins. The nut is driven by a timing belt "about" 50 teeth and the motor has an about 25 tooth pulley. I'm thinking a 400 in/oz. NEMA 23 stepper should work. Assuming the 2:1 reduction each 1.8 degree step lifts the head 0.0005 inches. By 1/4 stepping I get 0.000125 per pulse.
When looking for a good design for the mini mill I was looking for a good place to put the ball screw. This design places it very close to the dove tail, almost touching it. Maybe 0.1 inch in front of the dovetail. The ball screw goes right where the current rack it the original design. I will have to remove the rack to fit the screw. So I need to select a belt type and size. My initial guess at this a the GT2, 3mm pitch and 9mm wide. Some one else used a XL type 3/8 wide and 0.2 pitch but I'm reading that XL is not the best for new designs as GT2 has a much improved both profile that eliminates backlash. I started to calculate torque and load on the belt then thought "Why bother?" the actual force is going to be whatever the motor can do as I'll set the acceleration limits until it start skipping steps then back up by about 30% or so. I might go with a NEMA 34 1100 in/oz motor if I need to. So I might choose a belt that can handle whatever the 1100 in/oz motor can do. Just looking to double check GT2, 3mm pitch and 9mm wide is reasonable. So I guess the best way to ask the question is what kind of belts are working well with motors in the 400 to 1100 in/oz. range. If there is any interest I'm modeling this in Fusion 360. and can share the CAD files -- Chris Albertson Redondo Beach, California ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
