I need your opinion about something, does it seems possible, with a CoreXY architecture, to have two separate X axis on two separate Y axis. With this, there will be four printing heads, one at each corner. Any idea?
A while back, I thought about using 4 SCARA arms on one printbed. That would make mechanics much easier. Problem was, there is no firmware to support this ( co-operation of n controllers with the need of a few more datalines ) and SCARA arms are tricky to build.
Yeah, I have already thought of it and what I was thinking was an extension of this architecture.
The coreXYU has mechanical advantages over a two gantry coreXY.
The non-moving X gantry adds its steppers to moving the gantry in Y, as the gantry will be the heaviest component you see the gain.
A dual gantry coreXY will have the same number of steppers and belts as a coreXYU, the only plus is you don't lose any X travel to accommodate the second carriage that the coreXYU adds to the gantry. However, you sacrifice Y for the additional gantry.
Now, if you're talking dual coreXYU, belt routing will definately be an issue. That and you'll need 8 steppers just for the XY table alone. Plus 4 for the extruders and atleast one for the Z, for a total of 13. Don't know of any boards that support that many...
Yeah, it will be very difficult to have this.
After thinking a bit more, a CoreXYU architecture seems to be good choice for what I am trying to do. Do you have any schematics to have a general idea of the motors positions?
The most straight forward stepper location is on the arms (lowest point in the picture below), where the belts make a 180 degree wrap.
Two steppers point up, and two down. So the arms will resemble two hammers, if you have an open frame like Hlidskjalf.
For Hlidskjalf, I added more pulleys on the side for a 2:1 ratio. More for packaging, and "overly complex" for most maker's tastes.
For Lars coreXYU project, think he used shafts to drive the belts so the steppers are at the base.