I Didn’t Know That...

Q. How do they put the hole in the needle of a syringe?

A. Syringe needles are made the same way as larger pipe, according to Bill Westendorf of Air-Tile Products Co. Stainless steel is rolled out into thin sheets, then wrapped around a die to form a hollow tube, which slides off the die. The joint is then heated to close it, in effect welding it shut. One end of the needle is then sharpened, while a plastic nub is fixed on the opposite end to attach it to the syringe.