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.
Is it safe to have dyed soft plastic have skin contact for prolonged periods of time? I'd check the rating of the plastic, wouldn't want chemical dye or softener to leach into my skin.
The vinyl of all headphones is plastic. I'm not concerned at all. The fear of plastic is mostly paranoia. The vast majority of micro plastics are from car tires yet that is not what people freak out about.
I painted cars for a long time and worked in heavy industry for awhile. I've been exposed to truly nasty stuff. Other than my horns, and third arm, I'm mostly fine so long as a full moon doesn't happen on a Thursday.
Plastics like this are generally stable. TPU is used in the interior of your car and the grips on power tools. There may be some in your sports clothing. You are likely eating food that is packaged in PLA and PET. There is ABS is everything. These are all around you and come in printable forms. The colors made in the modern world are not arsenic, mercury, chromium, and lead based, like was common 200 years ago.
The majority of microplastics are from synthetic fibers in clothing, actually. Your point is valid though.
"But I only eat canned food!" Canned food containers are plastic lined, but don't worry - we've moved from BPA linings to less studied linings that are totally safer in the long run
"Paper cups and containers!" If it's touching something wet, odds are they have a plastic lining
"But I drink soda/beers out of metal cans!" Oh, hum
"Glass containers!!" Many have plastic on the metal lids
Etc etc. If you eat out you're eating tons of food that was heated and/or kept warm in some kind of plastic liner.