mystery solved!
Saturday morning, as I was loading up my rotary cutter for a trip to the welder, I had it at eye level and noticed something that I had missed when it was on the ground: the whole deck was bent downward by at least 1.5 inches. Suddenly it all became clear, and the reason for the cracks on the sides of the deck was obvious. Also, I had been wondering why my rotary cutter seemed to be cutting closer and closer. Now I know why. The deck was being bent downward more and more so that at the front , the tip of the blade got closer and closer to the ground. When I got to the welding shop several farmers had bushhogs there being repaired. I noticed that every one of them had angle iron or the equivalent welded across the top of the deck to keep the deck rigid. The welder had to turn my rotary cutter upside down and use a come-along and a big wooden block to pull the deck straight (actually reverse bowed a little to account for spring-back). Then he welded some angle iron on the edges to hold the deck straight when he released the come-along. He next turned the deck over and welded two heavy pieces of angle iron on the top to make sure the deck stayed rigid. He finished up by spray painting the whole rotary cutter. Total cost was $80 plus a $10 tip, plus a half day of my time. Moral of the story. With heavy use, the rotary cutter deck will bend and become permanently bowed downward. It has nothing to keep it rigid except the deck plate itself and some flat reinforcement strips on the underside. On a 4 foot span neither is sufficient to prevent permanent deforming of the deck. Terry says they have never had a problem with the rotary cutter deck, but if that’s true, its because no one has reported it. In my humble opinion, and with due respect to Power-Trac, the lack of support (like angle iron or the equivalent) for rigidity on the rotary cutter deck is a design flaw. If you use the rotary cutter hard, you WILL bend the deck. It is an easy fix to stiffen up the deck. I am enclosing some pictures of my fix. The first one shows the whole deck. The second one shows a close up of the angle iron that was welded on the top and sides of the deck. I hope no one has the problem I had, but I will be surprised if some of you don’t. Ken in Mississippi.