I have just completed the construction of my gas powered mulcher. The soil, or lack there of, here in West Bay, Cayman Islands, is more like concrete than soil. I have an abundance of yard waste from all of the ficus, hibiscus, bamboo, etc. I figured the best way to improve my soil is with compost/mulch.
I installed a lawn mower engine and blade on top of a 55 gallon drum that I cut down to approximately 20 inches tall. I then installed a chute for the debris to be dropped in. Instead of sucking the clippings, leaves, weeds, and such into the barrel, it blows it back out, just like the exhaust chute on the typical lawn mower. Realising that a lawn mower cuts grass from the bottom of the blade, I need to change the pitch of my blade and sharpen the edge so it cuts from the top. Has anyone experimented with this? In theory it should work famously, but an out of balance blade could be disasterous!!!
Have done it modifying an old lawn mower. similar arrangementexcept feed shute on the side so that works more are less like a regular lawn mower. Put 1/2 inch mesh in the discharge to to get the right size. Works well for leaves.