Originally Posted by
Aaronem
I am currently trying to extend my 1200mm x 1200mm (4ft x 4ft) gantry router to 2400mm x 1200mm (8ft x 4ft). I am being told that a 2400mm long screw is going to whip around like mad, and I believe it, and that I would be better off using either a belt or rack and pinion. Belt seems preferable because the stepper motor does not have to move around, but do belts work reasonably well?
Also at the moment one revolution moves the axis 4mm. With a pinion or a toothed wheel the axis will move maybe 75mm to 100mm. Will I need to gear down the motor and is there a cheap way to do this.
My gantry weighs about 75 kg, I have nema 34 steppers with fairly powerful micro stepper drivers
I would really appreciate some thoughts or experience on this.
Cheers
Aaron
You could always do a rotating ballscrew nut. The screw would stay still and the nut would rotate, eliminating whip.
http://www.glenspeymillworks.com Techno LC4896 - 2.2Kw Water Cooled Spindle | Moving Table Mill from Omis 3 CMM, 500Lb granite base | Epilog Legend 32 Laser Engraver