Unloading filament?
I've just did my mk2.5 upgrade and its printing really well on filament change however i've notice the filament is retracted but by the time it reaches the point the LCD tells you to remove the filament immediately a blob has formed on the end making it difficult to remove (and will eventually cause a clog). Is there a way to speed up how quick the filament is retracted on unload so it doesn't have time to cool and form a blob? Failing that i guess i could just over heat the nozzle before unloading as i guess it will take a few seconds longer to cool and harden.
Just wondered what other peoples experiences are and their solutions?
Re: Unloading filament?
I haven't had this issue yet. Perhaps me replacing all my PTFE with Capricorn blues helped? They are purported to be far more dimensionally accurate and consistent as well tolerating higher temperatures, more slippery and less flexible. This is speculation. But since I work with mostly PETG, which has the highest thermal retention thus prone to blobbing, maybe worth a shot.
I also shaped my guide tubes (there are two in MK2.5 extruder design) with chambered inner edge and flared receiving end ( meets Bondtech gears) as I found with stock PTFE tubes from factory. Though it might be best to modify aftermarket tubes while disassembled as a piece of errant PTFE rendered a nozzle worthless.
MK2S kit owner since 8/15/2017
Re: Unloading filament?
I extract a bit of filament before unloading.
No more blob.
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Gert
Re: Unloading filament?
A simple trick is to start putting a little tug/back pressure on the filament once you have pressed the button and continue to do so until it is out. Not a lot but you will get a feel for it after a few times.