11-13-2012, 11:13 PM
(11-13-2012, 10:31 PM)f350ca Wrote: Looking good.
When you say the Y axis is driven from both sides, does that mean two motors?
In this case it does.
There's basically three options for the Y, all of which have their pros & cons.
1: single side drive. Cheaper on the electronics & easier to setup once built but lacks rigidity and risks of wobbly cuts during direction changes when cutting at the far end from the driven side. Also requires a bulky driven end which means rails on that side longer than the usable table space. Usually ends up in a gantry heavier than other designs to try build in the required stiffness.
2: both sides driven with one motor. Again cheaper on electronics but requires careful planning to include a method of supplying drive to both sides, usually by a shaft or center mount, dual shafted motor driving a shaft to each side. Depending on design, this can lead to the lightest assembly but can be a pain to setup square to the X-axis.
3: Both sides driven and having a motor dedicated to each side. more pricey to build in most aspects, generally slightly heavier. However can be setup to Automatically Square itself when the axis is sent "home", is rigid and doesn't require a means of transferring drive to the other side.
As you'd already be aware of there's also the option of direct drive- cheap and nasty, reduction belt assembly- mid price and tuneable swapping pulleys, finally gear reduction drives- simple but pricey for minimal backlash.