moggieuk / Happy-Hare

MMU software driver for Klipper (ERCF, Tradrack, Box Turtle, Night Owl, Angry Beaver, 3MS, ...)
GNU General Public License v3.0
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Different speeds for loading and unloading the filament. #537

Open porar-oss opened 2 days ago

porar-oss commented 2 days ago

Greetings.

During testing, the mmu type B found that in the case of loading, the speed of movement of the filament is limited by the mass of the coil with additional resistance from the Bowden tube. In the case of unloading, the resistance of the coil remains the same, and the resistance of the Bowden tube becomes less.

The specific speeds of 265mm/s are loading, 300mm/s unloading (these are the speeds at which the mmu worked stably). The data were obtained using nema17 17HS4401 motors, supply voltage 24v, current 0.8A. BMG gear, with a 20:16 step-up gearbox. The length of the bowden is 1500mm, the inner diameter of the tube is 2.5mm.

During the configuration, Happy Hare found that it is not possible to simply set different speeds for loading/unloading the filament. I think such functionality can fine-tune the mmu in order to save time changing plastic.

P.S. for speeds of 265 and 300mm/s (for loading and unloading, respectively), the time gain is about 6%, compared with a speed of 265mm/s for both operations.