Overview
The Tsunami Ear Saver is an attempt by the Signal Processing and Instrumentation Section (SPIS) at NIH to develop a reusable device to reduce the pressure placed on ears by face mask straps. The design is optimized to be laser cut from 1/32” acrylic. It costs $0.70 to produce and can be cut in 50 seconds. The thin acrylic used is easily cleaned with soap and water or hydrogen peroxide. We provide 2 sizes, a standard size which fits most adult heads as well as a smaller size for people who find the standard size uncomfortable.
Background
The goals were a low-cost design that could be produced quickly and cleaned easily with commonly available supplies. None of the SPIS 3D printers could produce parts in a way that met all goals, so we developed a 2D design that could be cut from bulk acrylic on a laser cutter. The first designs provided many hooks to adjust for comfort and different mask types, but the hooks became tangled in long hair. This flaw inspired the Tsunami Ear Saver, named after the shape of the mask strap hooks.
The Tsunami Ear Saver features a long rectangular back and 3 sets of hooks on each side for tension adjustment. The hook’s unique shape reduces the chances of hair tangling and the long rectangular back places the hooks on the side of the head, away from where most users’ hair was concentrated.
Material
The recommended material for the Tsunami Ear Saver is 1/32” Rowmark Value ADA Alternative Bright White Engraving Plastic. This material is flexible enough to conform to the back of the head while durable enough to not snap under the tension of mask straps. Unlike many 3D printed materials, the homogeneity of laser cut acrylic allows it to easily be cleaned with soap and water or hydrogen peroxide.
The design was also tested with both 1/16” and 1/8” cast acrylic sheets and neither size was suitable. 1/8” acrylic was determined to be too stiff as users complained of discomfort and 1/16” acrylic broke easily during testing.
Production
Our Universal Laser Systems PLS6.150D laser cutter can cut a 12 x 24” sheet of 21 ear savers in about 18 minutes. The only post-processing step is to remove the protective film that is attached to the top side of each sheet. We also advise each user to wash the ear saver before the first use to remove any residues from the cutting process.
Alternative Manufacturing
While this design is intended to be laser cut from 1/32” acrylic, it could also be produced by other means. We include STL files for the design so that it could be produced on 3D printers, however we encourage users to consider material properties (especially biocompatibility), production times, and sanitization needs when choosing an alternative manufacturing method.
Design Files
A variety of design files are provided to make the design accessible to a range of users. This package includes the final design for both sizes as a SolidWorks model (sldpt), Corel Draw (cdr), Dxf, and STL.
Disclaimer
The device described here along with the accompanying files is experimental in nature and has not received regulatory approval for use in humans or any other use. CIT does not warrant its use for any purpose and disclaims all liability for its use. By using the enclosed plans, the user agrees to accept all liability.
