The Hula Dance is Shaking My Printer Apart
Since adding the Hula feet my table shakes a lot less but my printer shakes a lot more. I've started to notice more loose or detached screws than before I switched. I'm going to assume this is caused by the printer shaking more than it used to.
I suppose I can start using Blue Loctite everywhere but I'm going to switch back to the previous TPU static feet and see if that changes things.
RE: The Hula Dance is Shaking My Printer Apart
I would have expected that the vibration frequencies supported by the heavy printer mass and soft Hula-feet spring constant are too low to shake any screws loose. But as another data point, my printer sits on a sturdy bench and its standard L-shaped feet, and I have only noticed one loose screw so far. (And that one I very likely did not tighten properly: It was one of the two screws I had added to attach the door handle to the polycarbonate sheet.)
RE: The Hula Dance is Shaking My Printer Apart
It's nothing new that screws fall out due to constant vibrations and oscillations. I can't understand why Prusa doesn't mention using Loctite in the assembly instructions.
I also wanted to use the HULA feet, but I'm still struggling with the TPU part. In the meantime, I'm trying to use rolled-up rubber rings.
I can't test it on the Prusa C1+ yet, as it won't be delivered for a few weeks, but I'll test the alternative version on the Prusa XL with a homemade enclosure.
I suspect the TPU ring is too soft and the printer vibrates too much.
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Not an engineer so it's just my highly subjective opinion. I'm going to switch back to the TPU feet and if I notice improvement (again subjective) I'll stick with them. Otherwise I may remount the Hula feet. For reference, this is the table I'm using: Stationary Shop Stand
RE: The Hula Dance is Shaking My Printer Apart
While upgrading the last of my Mk4S to Core One I added Hula feet because they looked cool. After a few weeks of crazy Hula dancing I reverted back to https://www.printables.com/model/1303606-prusa-core-one-feet-v2-prusa-rubber-feet-reuse plus paver. I couldn't handle the excessive shaking of the printer anymore. I guess if they do the job for some people, great for them. But for me it's another example of something that on paper sounds like an improvement but doesn't survive contact with reality, very common in our space.
Formerly known on this forum as @fuchsr -- https://foxrun3d.com/
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While upgrading the last of my Mk4S to Core One I added Hula feet because they looked cool. After a few weeks of crazy Hula dancing I reverted back
I did exactly the same yesterday. They look cool but then I can't help but think my printer will shake itself apart. For me it was a "Solution in search of a problem"
RE: The Hula Dance is Shaking My Printer Apart
I'm not an engineer, but the HULA foot is only half a solution. As with a car, damping and suspension must be in harmony to function properly. In my opinion, the TPU ring is not ideal and is too general for all printers.
RE: The Hula Dance is Shaking My Printer Apart
You move the self resonance to lower frequencies with softer rubbers, so stuff can happen and move in new ways that it doesnt do in the std setup. Maybe just make the bench sturdier and heavier, the std rubbers works great on my heavy sturdy bench. But I understand many people dont have such workbenches at home 🙂
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Not an engineer so it's just my highly subjective opinion. I'm going to switch back to the TPU feet and if I notice improvement (again subjective) I'll stick with them. Otherwise I may remount the Hula feet. For reference, this is the table I'm using: Stationary Shop Stand
I am surprised that your printer still moves on top of that table. Mine is not that different (it has metal sides instead of the huge metal columns) and, using the Prusa original rubber feet, the core one doesn't even vibrate...
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Not an engineer so it's just my highly subjective opinion. I'm going to switch back to the TPU feet and if I notice improvement (again subjective) I'll stick with them. Otherwise I may remount the Hula feet. For reference, this is the table I'm using: Stationary Shop Stand
I am surprised that your printer still moves on top of that table. Mine is not that different (it has metal sides instead of the huge metal columns) and, using the Prusa original rubber feet, the core one doesn't even vibrate...
Indeed it's a very stable table. I think (in my case) I was still in the honeymoon phase of trying out every mod I could find on Printables, stumbled across these and thought: "ohh shiny". I already had the same thrust bearings I used on a completely different project (a telescope mount) so I thought to give it a try. I've since switched back to the TPU feet.
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The TPU padded feet are better in my opinion. Ironically the printer and table shake less than with the Hula feet attached. I guess I would argue that the Hula feet are another example of a solution in search of a non-existent problem. I guess this is a case where it's better to have the printer more tightly coupled to a rigid structure, i.e. my 45kg table.