So i notice with this one, the roller wheel rolls right on the cutting surface. This means that the path back and forth across the table has to be kept free of chips or even an accumulation of sawdust so that the machine doesn’t go over top of this and the z-axis doesn’t get raised by a mm… This seems like a part of the device that would be prone to error.
I’m wondering the advantages/disadvantages of using bearings and a stainless rail (like the mpcnc) on the side of the table with a brace at the midpoint to keep it rigid. It wouldn’t be terribly difficult to get the two rails parallel.
True. A vac helps, or you could put a little sweeper near the wheels if you had an issue, or use angle as some have as a track and debris deterrent. There are a ton of options. When cutting all the way through, this isn’t really and issue, and if you have pockets maybe a bit more so but generally in giant projects a few tenths of a mm are not that bad. Tolerances are built into projects.
You also have to see any error will be an angle, one wheel up one mm is averaged with the other wheel that would be half, then that distance is a factor of the angle created with the other side and the distance to the cutting bit between the rails. So on the far side…basically nothing nearest the rails much less than .5mm for a 1mm deviation of one wheel as the bit is minimum of 7" from the wheel.