Extruder skip steps on fast-ish retraction (A30T)

[airbrett]

First off thank you so much for your efforts on the Geeetech A30T, it's such a huge improvement over the SmartTo firmware.

The problem I am facing on my printer is blobs at the start and end of a line. To combat this I am trying to tune the retraction but I cannot command the extruder to move filament faster than 20mm/sec without skipped steps. Reasonable speeds like 40mm/sec are out of the question. I think I went up to 60mm/sec with the SmartTo firmware (after raising the max feed rate) but I can't confirm this (I haven't been successful in flashing my backup back onto the printer).

Are you seeing the same 20mm/sec limitation on your printer?

[TheThomasD]

Hey, I'm sorry I didn't reply sooner. I haven't used my A30T in a while and wanted to improve the display software today. If I get it running I'll try the retraction speeds on my end. As far as I can remember, I definitely used more then 20mm/sec. However, I also replaced the original extruders to non-geared ones (see picture).