So I am new to this and looking to build a small wood cnc router, I was looking at the 40x40 kit and after about a week of research I see many of these kits use a stepper motor on both sides of the main table with a belt drive. how are both motors controlled exactly the same? I was looking to control mine with a GRBL shield and an arduino. but that only has 3 motor drivers. Would it make more sense or be possible to have a single ball screw in the center with a cross beam under the table instead of the 2 belts? Thanks in advance for the help.
I see so something like the TinyG it has 4 motor drivers. Would it not be wise to try a center screw drive with a single stepper?
I understand the desire for a single motor but implementing it can be a bit of a trick. Of all the designs posted here on the forum I can't recall anyone having even tried.
I built my first router out of MDF with a similar design. The problem is that the gantry can rack or twist a bit, making your x-axis not exactly perpendicular to your y-axis and leading to making a parallelogram when you are trying to cut a square, i.e. the corners aren't exactly 90 degrees. The dual y-motors mean that when you tell the router head to move 2 inches, both sides move exactly 2 inches, keeping the gantry the same distance from zero on both sides. While it seems more difficult to set up, it really isn't with most boards that get recommended on here. It's one more motor and one more run of wire to have a router that has WAY more accuracy and repeatability, key factors for most CNC router usage.