I've been working with a Chimera+ (air cooled) for a few months. I've been having oozing issues the whole time. The hotend will ooze indefinitely when left idle at print temperature. This particularly becomes a problem since the idle hotend will eventually starve itself of filament. Then the hotend becomes active but has no filament primed to print. Details: PLA Hotend @ 190-200 degrees ~300 mm Bowden tube (as provided in the Chimera+ kit) 4mm retraction and 4mm tool-change retraction 0.4 mm brass nozzles (previously also had 0.3 and 0.4 mm hardened steel nozzles) I believe the "proper" solution to oozing is to simply increase retraction distance. However, the old Chimera documentation warns you to avoid increasing retraction past 5 mm. In my experience, 4.5 mm and above of retraction distance reliably clogs the heatbreak with cooling PLA. However, I believe it is quite standard for Bowden extruders to require 5-8 mm of retraction. This likely holds up well for the tool-change retraction as well. Also to note: The new Chimera+ guidelines say to keep retraction at or below 2 mm. At this distance, I am experiencing constant (fine) stringing. 3-4 mm seems to be the most reliable for me. -- Questions: How can I get the hotend to stop oozing? The oozing needs to be negligible over >1 minute so that the other (active) extruder can print 2 full layers without interruption. Slic3r can reduce the inactive extruder's temperature, but in the time it takes the extruder to drop ~10 degrees, I get 20 mm of ooze. This is obviously unacceptable for essentially any print. Do Bowden extruders generally require 5+ mm of retraction? If so, why does the design of the Chimera+ heatbreak preclude this option, especially when the system is designed to be installed in a Bowden configuration? Thank you for any help!