Elmer, I made one for next to nothing, two computer fans, some scrap plywood, a piece of vaccum cleaner hose, 5 gallon bucket, some old sheet metal, and an old pair of panty hose. More then likely, you've got most of that stuff laying around the shop, shed, garage, or basement. (if you go cat fishin, check your tackle box for the panty hose

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Click on the link below for my photo album, there's a few pictures there. If you need more info just ask.