I've made ~150 chisels over the years. I've built them for my bosses friends and to offer for sale. I live on the Minnesota River and that was the primary way of making a spear hole until, and even after the chainsaw came along. The ONLY one I have was one I made FOR myself. Here's my 'recipe': 1/2"x 3"x 6" piece of truck leaf spring (aka, the blade). A torsion bar from an older Chrysler product about 30" long with a 3/4" to 1 1/2" pipe reducer welded on the "north" end. then a 2' length of 1 1/2" pipe with a cap and an eye-bolt welded (from the inside) in the top end, then I filled it with lead. If you haven't deduced by now, It's a 2 piece, that breaks down to about 32" max length. I've had this chisel since the mid 70's and the only way anyone
will get it is to 'pry it from my cold, dead hands'.
But, I could send pics!! Post your email, I have the pics. Phred52