I am actively developing this. I am going with a single motor for the z and a single motor for the filament drives. Here is the plan.
The z will pull all up at one. Each side will have a spring loaded platform for independent adjustments.
The filament drive will have a long shaft that has been hobbed 4 times.
If a quadrant messes up you can keep running by releasing the idler for that quadrant and then turning that hot end and heated bed off. I think I will keep all the temp control separate from the controller board. I will have 8 knobs connected to some simple pwm circuitry.
Homing is going to be manual. You push the hot end all the way in or pull it all the way out and then rotate the arms to be centered on a platform. You also push the beds to the bottom position. You only have to do this once while it is being continuously powered. That could be months between homings. I will build in a larger than normal factor of safety so the chance of skipping steps will be relegated to the occasional cosmic ray instead of the occasional bump. With 4 heads that only need to go 60mm/s that should not be a problem.
The z will pull all up at one. Each side will have a spring loaded platform for independent adjustments.
The filament drive will have a long shaft that has been hobbed 4 times.
If a quadrant messes up you can keep running by releasing the idler for that quadrant and then turning that hot end and heated bed off. I think I will keep all the temp control separate from the controller board. I will have 8 knobs connected to some simple pwm circuitry.
Homing is going to be manual. You push the hot end all the way in or pull it all the way out and then rotate the arms to be centered on a platform. You also push the beds to the bottom position. You only have to do this once while it is being continuously powered. That could be months between homings. I will build in a larger than normal factor of safety so the chance of skipping steps will be relegated to the occasional cosmic ray instead of the occasional bump. With 4 heads that only need to go 60mm/s that should not be a problem.