Scrappy CoreXY Arm variant dry run.
Lots of work ahead (need to get a Z probe in, actually mount the hotend, etc etc) but the basic motion control is working as expected for gross motor control.
Can’t wait to see the first crappy prints from this beast!
I have a plan for calibration that should - in theory - let me super sloppy with bed placement.
Basically the Prusa Original technique, but assuming that the XY is orthogonal, instead of assuming YZ is orthogonal.
Ohhh I like it very much, can I play??
Ha! Let me make a first print before you sink time into this one!
I just like the coolness efect
If you’re going to let one metal rod slide on another like that, you should put a better bearing surface between them. I would go for UHMW tape. You can wrap it around the moving rods to reduce friction and damage to the metal.
It’ll shure bend when the effector on the far right, away from motors on the left. Especially on the rapid movements. And if it catches a resonance it can get pretty bad.
I’m afraid you’ll have to decrease the speed a lot during some prints.
I’m not a fan of such complicated setups. But it’s an interesting one nevertheless.
I think we should come up with a new name for this. ArmCore? Heh.
I would consider this to be within the category of belt layouts that I’ve been calling Core-T (because they’re T-shaped and work like CoreXY).
I like Core-T - although developed independently, @Whosa_whatsis does have temporal precedence on the idea to me.
Btw, with four more pulleys (minus the two unnecessary ones you have) and an even longer belt that is fixed near the motors, get an additional 2x pulley reduction on top of the normal sqrt(2):1, for a resolution increase of more than 2.8x compared to a discrete cartesian bot. You do have some belt intersection issues to worry about on one end, which is why I didn’t pursue it further, but those can probably be solved the way that a typical corexy does it.
One very minor advantage - belt tension can be easily adjusted by bolts that go through trapped nuts, and push directly on the end rods.
Since this endcap is not tied mechanically to the supporting rod under it, easy to do, and even adjust the tension while running.missing/deleted image from Google+
