These injection molded filters made for the medical market have more than 1,000 76-micron (0.003 inches) squares with wall thicknesses of 0.006 inches. "The previous way to make a filer was to run a metal mesh through an injection mold and then mold a frame around it," comments Donna Bibber, vice president of sales at Miniature Tool & Die. The trend to minimally invasive surgery is triggering a boom for micro components that travel through blood vessels. "Everywhere we turn there is a challenge we have to overcome,"
comments Bibber, a plastics engineer. Example: MTD had to develop a 7-gram hopper for resin drying. Conventional dryer hoppers are in the 150- to 200-lb range. "Also, we don't always have the luxury of a surface we can eject on to," she adds. MTD often ejects from runners or gates. For more information, go to http://rbi.ims.ca/4922-503.