Gary,
Have you tried a shallower cut with faster feed with the 3 flute? You ought to be able to get enough advance per flute that way, you'll need air to clear chips and cutting lubricant (WD-40 or a 30/70-20/80 engine oil/paraffin mix) to reduce chip adhesion to the cutter, a quick squirt into the cut once every pass or two is usually adequate,

- Nick