Dual drive extruder gears including the ones in our Prusa Mk3 printers - Interesting video
I think most are aware of the zebra stripes you can see with a mk3 on vertical surfaces. There's even a calibration print on prusaprinters from Prusa to test for it and try to compensate yet I never could really see much difference. This video and the follow up proposes an idea why we see this sort of artefact on printers including ours. Thought it was worthy of sharing and discussing.
What I've learned about your 3D printers (and mine)
This is AMAZING to see! I'm so thankful I'm subscribed and get to see the content you make. You're methods of investigation are great, and you're testing every permutation. I cannot wait to see more.
So - throw out the gears?
And what is the proposed fix?
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FYI I am not the person who made the videos. I merely think it's interesting and love someone went to that level of detail in studying the 'issue'.
As for a proposed fix, some suggestions are made but I think there will be more to come in this area.
RE: Experimental alternate idler door design provided
And what is the proposed fix?
He's got a good summary on the tradeoffs at about the 7:30 mark on the 2nd video:
There's an alternate idler door design provided in the links for the Mk3. If you're willing to give up on printing flexible, you might not need to do much.
The root cause does seem to be the dual-gear Bondtech extruder gear design. I'm ot sure of geared extruders will have same issue, but I'd think so. It is interesting that the single-gear extruders on my Sidewinder and (cheap) Cadet don't have this specific issue. Once I get my Mk3 back up and running I'll do more comparisons.
Do watch to the end. This doesn't fix all issues.
and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan