I am quite satisfied with my moving gantry machine (see the Big Bamboo thread) but once a while I want to do something bigger than the 34"x31"x8" range allows for.
I surely can not set up a full size 8'x4' machine but was wondering if I could do a 8' or maybe 9' by 31" moving sled as a compromise. That would be a removable table, maybe on skate bearing slides that is clamped to the extrusions of the main table. While the gantry moves left (-x) the sled would move right (+x) and vice versa. I might even use my rotary A-axis stepper with harmonic drive reduction to actuate this sled (steel cable or belts). The Planet-CNC controller allows for slaving this 4th axis to "x" but I need to check if it can do that with different steps/inch. When I don't need the long travel I would just take the sled off and store it vertically in a corner of the shop.
Anyway, it looks like a wacko compromise but has that been tried before?
Thanks, JB
I surely can not set up a full size 8'x4' machine but was wondering if I could do a 8' or maybe 9' by 31" moving sled as a compromise. That would be a removable table, maybe on skate bearing slides that is clamped to the extrusions of the main table. While the gantry moves left (-x) the sled would move right (+x) and vice versa. I might even use my rotary A-axis stepper with harmonic drive reduction to actuate this sled (steel cable or belts). The Planet-CNC controller allows for slaving this 4th axis to "x" but I need to check if it can do that with different steps/inch. When I don't need the long travel I would just take the sled off and store it vertically in a corner of the shop.
Anyway, it looks like a wacko compromise but has that been tried before?
Thanks, JB