Originally Posted by CuttersCov Shopbot seems to over come this problem of backlash from a wide gantry design, so I may end up making my gantry supports 6" wider |
The ShopBot is driven from both sides, so you can't get the skewing of the gantry you're seeing. My machine is the same way, and a lot of others are noticing it too. Bottom line seems to be that you must drive the gantry from both sides to prevent this. I'm pretty sure even a very solid and heavy steel gantry would do the same thing to some extent, unless the bearings are spaced very far apart, maybe 2 feet or so, with good linear bearings.