A replacement for the tiny little gasket on the Welch Allyn KleenSpec Disposable Ear-Specula Dispenser for 521-Series Ear Specula (for Pneumatic, Operating, and Consulting Otoscopes) and Part number 521000.
The stock gasket is very functional, but as anyone in medicine knows who uses these on a regular basis, it frequently becomes pulled off over time. The housing becomes damaged or fractured as beds and IV poles smash against them when cleaning and managing critical and unstable patients.
This replacement is designed to replaced the existing one. Im attempting to develop another which offers more support by extending deeper along the tubing assembly. Finally, I plan to develop a 3D modeled replacement for the entire assembly of the 521 Series Ear Specula/Otoscope tip (Part 521000) which costs about $355 for 10. Unfortunately, I don't see an ability to purchase the gaskets individually from the remainder of the assembly, nor can I see the individual to buy one single assembly.
Ninjatek Cheetah TPU TPU
I modified my Prusa i3 MK3 with the Diabase Flexion HT extruder so I can print higher quality TPU prints. That may be necessary...I'm not sure how well it works on stock MK3 that's well tuned in.
I tried NinjaTek NinjaFlex TPU (Shore hardness 85A), but it seemed a little too flexible. You may be able to use it if you thicken the teeth further away from the core of the gasket (towards the floor and away from the otoscope tube holder). NinjaTek Cheetah TPU (Shore Hardness 95A) seemed to be better but that may be that I'm more experienced with it.
You'll NEED to do custom supports to print. Simplify3D is very useful since you can add in custom supports of the size and location that you want. You can't use automatic supports.
Print in the orientation as shown with the teeth on the TOP. This allows for proper printing of the gasket assembly so that it can properly lock onto the holder. If you print the teeth on the plate surface, the attachment rings on the inner portion of the gasket will not have support and will potentially fail.
Make small supports (I used 2.75mm supports) that are manually placed at the very edges of the gasket. If you place them at the tips of the teeth (closest to the center of each tube), then the support can easily be clipped off the model without any difficulty.
I'm in the process in making a gasket that extends up higher, but I'm trying to find the best method of orienting it so it prints properly. But in the current orientation, it doesn't seem to print the ridges as precisely as I'd like. Model TBD.
Clip off the supports. Mount so that the teeth extend on the inferior aspect of the assembly.