Although picks, or plectra, for playing musical instruments are commonly plastic injection molded or stamped, some are machined.

For example, Machine Control Technologies Inc., Corona, Calif., built a grinding machine for a pick manufacturer to produce picks made of polyether ether ketone (PEEK), said Sam Yu, company president. He added that PEEK is a tough material that won't chip and positively impacts the sound of a stringed instrument.

According to Yu, the unique CNC grinder is equipped with an autoloader. The diamond wheel follows the pick shape and produces a beveled edge on both side of the pick.

After achieving a return on investment after 5 months, the customer purchased a second custom grinder, Yu said.

Other CNC machined picks are available from BlueChip Picks Inc., Knoxville, Tenn. The picks are named after the company's machine shop, Blue Chip Machining Inc., but are not blue. The specially formulated composite material used to create the picks is brown as a result of the complex chemical makeup and the processes it undergoes, the company reports. It added that the material contains special lubricants, which make the picks fast off the strings.

The cost of BlueChip Picks range from $35 to $75 because of the cost of the heat- and wear-resistant material and labor involved to create them, according to the company. The picks are CNC milled, then beveled and polished by hand before being laser-etched.

The numbers on the picks represent thickness measured in thousandths of an inch, such as 35 for 0.035" and 50 for 0.050".