With so many ways to formulate plastic to get just the right combination of color, texture, strength and durability, it’s easy to forget how the parts will be assembled. However, if the parts will be assembled with screws, overlooking such parameters as thread style, driver speed and boss design could spell disaster on the assembly line.

Laser welding of plastic parts creates precise, high-quality, particulate-free joints for medical devices, consumer products and other assemblies. However, for the process to work, the laser light must pass through the top part to be absorbed by the bottom part. Welding a clear plastic part to another clear plastic part was not possible.

ROMEOVILLE, IL—A group of 20 workers at an auto parts assembly plant here walked off the job April 6 and announced they will quarantine themselves after a co-worker tested positive for the coronavirus.

DETROIT—This week, union workers at a Ford manufacturing plant outside Detroit raced to set up new assembly lines. But instead of making hybrid car batteries, the usual output from the factory, they are preparing to churn out tens of thousands of ventilators, joining the sprint against the clock to fight the coronavirus.

How quickly things change. On March 1, I was one of 15,000 people watching the Chicago Cubs play a spring training game at a ballpark in Mesa, AZ. It was warm and sunny, the beer was cold, and I had not a care in the world.