Agar is a naturally occurring gelatinous substance derived from seaweed. When used as a binder system in MIM materials the aqueous agar-based binder is debound through short air-drying. Other binder systems require expensive and time-consuming thermal or solvent debinding and are much less environmentally friendly.

The new agar-based feedstock lets designers build MIM parts in excess of 200 gm and with wall thicknesses > 0.25 in. Parts this size are reportedly more difficult to debind in a time-efficient manner with other MIM feedstock systems.

A case in point is a new putter from golf club manufacturer Ping Inc. Ping needed to combine custom club specifications with an efficient production process. They worked with the Powder Metal Products Div. of Remington Arms Co. Inc., Ilion, N.Y. (www.remingtonpmpd.com), a pioneer in the use of MIM materials. Remington Arms recommended the agar-based feedstock called PowderFlo.

According to Matthew Marley, operations manager for Remington's Powder Metal Products Div., "PowderFlo compounds let us consolidate a stainless-steel putter blade and nozzle into one part. The feedstock is both consistent and predictable. Even with this large part, controlled moisture content helps us keep dimensions in close tolerance. This application would not be economically or commercially possible using other MIM feedstocks."

To further customize the putter, Ping adds a range of high specific-gravity compounds to the back of the blade. This imparts heft to the club that's keyed to the preference of the individual golfer. The combination of four different blades and three different back weights with different geometries lets Ping market a "customer specific club," says Marley. "It also lets them take advantage of the unique properties of different materials each in a single, efficient process."