For almost three months, MU’s College of Engineering has been cranking out face shields, testing swabs and ethanol-based hand sanitizer in the university’s pandemic-fighting efforts.
And with just three weeks left before the start of the fall semester, efforts to produce 4,500 face shields for MU faculty are in high gear.
The university announced in mid-June that faculty would wear face shields while students will be required to wear masks.
The College of Engineering was asked to produce the face shields for the university by early to middle August. The lab was also asked to produce 2,000-3,000 powered air-purifying respiratory shields, 5,000 headbands for the simple shields and has continually 3D-printed testing swabs for MU Health Care.
As two MU staff members stood over a table last week in Lafferre Hall gluing soft plastic cuffs onto the powered air-purifying respirator shields, director of international programs Cassandra Siela compared the work to doing arts and crafts.
”It’s been fun,” she said.
Hilary Mueller, the college’s director of diversity and outreach initiatives, and Siela said college faculty and staff began producing masks at the request of the college’s administration, which asked engineering faculty and staff to do the work in tandem with their regular work.
Producing the shields has been an “all hands-on effort,” Siela said.
Mueller said she was inspired to help produce shields because she likes knowing she’s contributing to something bigger.
Since the college tested four versions of the powered air-purifying respiratory, or PAPR, shield with University Hospital, it has taken steps to mass-produce them.
The College of Engineering had made more than 2,000 simple face shields as of Friday.
The shields are made from polyethylene terephthalate glycol, which is made from recycled bottles, said Ron Monson, director of facilities.
When the pandemic hit, PETG was in short supply, but now the flow of production seems to have normalized, he said.
PETG comes in a 4-by-8-foot sheet that is machined into smaller sections by research engineering technician Ghassan Al Bahhash, who has worked with machines for 25 years and the university for 10 years.
Bahhash uses a mill machine to cut and shape the PETG for face shields in bundles of 36.
It takes about 15 minutes for the machine to mill one bundle, and he can manufacturer about 250 plastic shields a day.
“It’s not that difficult, and the machine program was easy to make,” Bahhash said.
At first, the lab cut the plastic shields with the mill, he said. Now, only the simple shields are milled, Bahhash said.
The lab cuts the PAPR shields using a side arm press with a clicker die, which allows the team to cut the shield and clips with one press in seconds.
“It’s like a giant cookie-cutter,” Monson said.
Rapid prototyping lab supervisor Michael Absheer said he has been 3D-printing headband prototypes for testing. 3D printing is primarily used for making prototypes because of how long it takes to print, he said.
Right now, the university is in the process of contracting with a company to mass produce the headbands with an injection mold, Absheer said. The contracted company can produce 5,000 headbands costing about $5 each, he said.
Absheer said he printed 100 headbands over the course of a month. The headbands would cost about $11 each if they were 3D-printed, he said. It is “way too slow to make thousands of headbands,” he said.
The type of printing he uses is called fusion deposition modeling, Absheer said. The method is similar to using a hot glue gun to layer materials.
Using an injection mold to produce headbands is similar to the way an ice machine makes ice, he said. The materials are poured into the mold machine and a headband is produced like ice from an ice tray.
The injection mold method can produce a headband “in a matter of seconds,” he said.
The shields and headbands are being produced in the same labs as swabs. University Hospital bought the College of Engineering five 3D printers with the agreement that the engineering department would print swabs for the hospital, Monson said.
He said, each machine prints one pallet, which holds 320 swabs, and the printing process takes about eight hours. After the swabs are printed, the resin must be cured in ultraviolet light and sterilized using alcohol, Monson said.
All of it is hard work.
“It’s wearing me out,” Monson said. “But I’m not complaining.”