Dave Dam is known for turning old artillery shells of various sizes into amazing steam whistles (Vol. 34, No. 5).

The Eau Claire, Wis., whistle expert recently turned a giant, 2-ft. long cast aluminum air horn made by the Westinghouse Air Brake Company into an attraction at antique engine shows. The flared end of the horn measures 10 in. in diameter.

“This air horn was originally designed to be used in trains and factories. I found it at a surplus store for $15,” says Dam. “The round end piece that contains the baffle - which causes the vibration that makes the sound - was missing so I made a new one out of aluminum. I also made a 5-in. baffle from stainless steel. I installed a pipe thread in the baffle and hooked a nipple up to it so I could attach an air hose.

“Sometimes I take my air horn to antique engine shows, where I hook it up to an air compressor tank in the back of my pickup. It sounds like a riverboat or a foghorn. I use a 100-lb. propane tank for an air tank and usually keep the pressure at 125 lbs. Any more pressure than that causes it to make a screaming sound that’s almost unbearable.”

Dam’s collection of artillery shell steam whistles has about doubled in size since FARM SHOW’S first report. He now has about 45 in his collection, and has another half dozen 21-in. tall, 105 mm Howitzer shells on hand. The biggest whistles can be heard a couple of miles away. He takes them to antique engine shows to blow for the noon whistle.