I recently finished building a Folgertech Kossel Delta 3D printer (http://folgertech.com/products/folger-tech-kossel-2020-full-3d-printer-kit), and am on to the setup phase. Following the instructions, I used the pronterface console command: G1 X50 F4000. This was supposed to lower the extruder nozzle to where it thought 50 mm above the bed is. The nozzle being far too high, I tried to steadily lower the X value in the command until the extruder was just touching the bed, as per the instructions (negative values were supposedly ok). However, I ran into a problem: the nozzle would not descend past where pronterface thought that X0 was, even with a negative X value. This is a massive hindrance to configuration. Does anybody know how to make the nozzle X value negative? Thanks!
TL

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The console command G1 XA F4000 will not lower past A=0. Does anyone know how to make A a negative number?