@clickclick thanks for the heads up. I've been trying to wear a mask more lately. I may have to invest in a respirator. The dust masks fog up my safety glasses.
@pappy, The metal base was originally a bolt. I turned the tamper on a pen mandrel and then epoxied in a 1/4 inch bolt. I rounded it off on my belt sander.
A friend of mine is a metal worker as well and told me he would make me caps once I come up with a few designs and can give him dimensions. Hes made quite a few tampers that have turned out really well.