Compliant tube based headphone pad idea I had while riding a bicycle two days ago. I got the thickness and dimensions dialed for printing and bending, but I either need to setup my old KP3 kingroon with a longer 2040 Z extrusion or print this in 2 pieces. Either way, the joint connection needs more than just the overlap and glue. TPE would probably be better too, although I have no idea what shore hardness this $10 clearance spool of TPU has. The sound quality seems a little tinny and I have no way to tell how loud it is externally, but it is just my first iteration that I can put around my ear and test. TPU is so slow to print and the moisture levels impact the qualities drastically. I actually like the texture and properties of wet TPU more than dry, but it is hard to get it just right. With the design’s compliant bend, consistency is kinda important. Anyways, just another boring project. On the bright side, this seems cooler temperature wise when the TPU pad is against my ear.

I spent all day chasing custom logarithmic infill patterns that might incorporate a compliant bend but only learned about how not to do a thing like that in CAD.

  • IMALlama@lemmy.world
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    16 hours ago

    This is very cool! Wear glasses and have been tempted to make my own TPU ear pads with some notches to better accommodate my glasses frames. That will obviously nerf the seal some, but it sound be a low cost reversible thing I can try and revert if I don’t like it.

    I was considering printing them with no walls and varying amounts of gyroid infill to get the right amount of squish.

    Be sure to post a follow up and impressions once you’ve used them for a little while.

    • j4k3@lemmy.worldOPM
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      16 hours ago

      Unless you’ve got a way to mathematically generate the change in infill, don’t bother. Lining up infill patterns and logarithmic strategies are hard. The solid parts are just as important as the flex. Keeping things straight is a challenge.

      • IMALlama@lemmy.world
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        15 hours ago

        I was thinking about doing this purely with a slicer and infill density. If it needs a solid layer or two for some reason you could leave top/bottom layers as non-zero.

        • j4k3@lemmy.worldOPM
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          14 hours ago

          The problem is that the infill layers are not well fused and the lack of alignment means they will only cross at angles. This post design can be made solid and turned into cubic with no anchor. That might work with a softer material, but there are still overhangs and the infill pattern is likely to create non linear twist to the bending. At least on my headphones, the tightest part of the bend needs to obfuscate around 60% of the vertical distance on the other side. In other (poor) words, for ever 10mm of vertical height, 6mm is folded out of the way. That is a lot of bulk to push out of the way. Even in this instance I posted, the back side has sections with thinner walls in some areas to make the flex work in such a tight bend without buckling.

          • IMALlama@lemmy.world
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            1 hour ago

            Oh, I see where you’re coming from - you want to print a straight line than you can bend. I was thinking to completely 3D print the pad and remove/replace the stock units. This would let me print them as an oval.