by TLHarrell » Fri Jan 17, 2014 7:47 pm
The smaller THK rail systems are sufficient to carry the laser optical head and an air assist. Benefit to THK vs round linear bearing is that you can side mount it to the gantry beam and it won't twist. THK is also much smoother than most wheeled variants. I have a unit made by Full Spectrum which uses wheels for both X and Y axis. There is a noticeable wobble to cut edges. When I have time, money and space to build a larger machine, I'll be removing this issue from the design by using THK.
For a larger machine, I'd probably be in the range of a 20x40 or 40x40 beam for the gantry.
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