“One of the more time-consuming parts to sew in this plan is folding bias tape in half and stitching it together to form the strings that loop over your ear or behind your head,” said Wynveen. “Bias tape has a bit of springiness to it because of the 45-degree weave angle. The tool we are 3D printing is a funnel that folds the tape back onto itself, so that when it exits the tool, it can be fed right into a sewing machine, or be ironed flat.”
Bias tape tools are available commercially, but a sewer who doesn’t have one on hand would have to leave home to purchase one – not advisable right now – or order one online and wait for delivery. Wynveen found a bias tape tool on thingiverse.com to design a bias tape tool that could be 3D printed and enlisted fellow development engineering manager Chris Jenks and Mercury Racing technician David Dins to help crank out the plastic tools. All three Racing employees are 3D printer hobbyists, according to Jenks, and one of them brought home a 3D printer from Mercury Racing to keep engineering projects moving forward while the company is on “work from home” status.
“The 3D printer community is finding many ways to help during the pandemic,” said Jenks. “PrusaPrinters created files with its local health ministry in the Czech Republic for face shields and shared them with its printer community. Those in the 3D printer hobby usually make small models or arts-and-crafts projects. I’ve been making motorcycle parts. The bias tape tool was something we could make quickly and share locally.”
The tool is designed to be handheld and forms the tape as it is fed into a sewing machine, or as it is ironed flat. Wynveen communicated with two Facebook groups coordinating sewing of masks in Wisconsin – Masked Sewists for SE Wisconsin (2,762 members) and Wisconsin Face Mask Warriors (3,963 members) – and on March 30 offered his bias tape tool. He then enlisted Jenks and Dins to help print the tools, or “formers.”
“We are printing 30-piece nests of four-centimeter and five-centimeter formers,” said Wynveen. “I picked that nest size as it’s about a 12-hour print, which best lines up with our human sleep schedules, and gets us 60 pieces per machine, per day.”