Question about early minting technology—how much of a problem were “sticky planchets”?

Longacre

I was reading Burdette’s Renaissance of American Coinage book and in one chapter he talks about experimental alloys used for coinage. In particular he discusses aluminum alloys. He writes,

“An early draft of the bill called for use of an aluminum alloy—something the mint had tested in the past but found unsatisfactory.” [Then Burdette quotes a letter from superintendent Landis to director Roberts:] … “In 1896 experiments were made in this mint with pure aluminum and alloys containing 97% and 98% aluminum. All of these were found to be too soft and clogged the dies.”


For the early minting gurus in the house:

(1) How much of a problem were these “sticky planchets” (for lack of a better term)?

(2) Was the technology not developed yet to prevent the aluminum planchets from clogging the dies?

(3) How similar is another soft metal, such as copper, to aluminum? I don’t know if the mint had trouble with copper planchets in the past clogging the dies. If not, why couldn’t the current technology be modified to assist with the aluminum planchet problem?

CaptHenway

Picture in your mind how the lettering and/or stars used in the late 19th century tended to rise up out of the field at nearly a right angle. Think of an Indian cent, or a Liberty nickel.

This is merely speculation on my part, but I would suspect that when you struck an aluminum planchet with a die with this type of lettering or stars, the soft metal would pack tightly into those letters or stars in the die and "stick" to the upper die as it withdrew. There would be little weight for gravity to hold it down, as compared to a planchet made out of copper or copper-nickel.

TD