Damn Machine . . .

The Damn Machine is a 3 inch Troy-Built chipper/shredder. It is a big red monster with a 10 horsepower over head valve engine and can allegedly chew up a 3" log. Well, my beloved and I were turning last year's leaves into this year's compost when, "Bam" out flies a thee inch piece of metal and the whole thing is so off balance it is tearing itself apart. I got it shut down before too much damage was done.

My mechanical curiosty got the better of me and I preceded to disassemble the monster. Not to hard, just a lot of bolts and occasional assistance from my honey on removing awkward assemblies. Got it apart and saw where the pieces known as flails had disintergrated.

Each flail had three fingers that are about three inches long by inch wide and maybe a quarter of an inch thick. And the flail was held in place by pin, about 3/8ths of an inch thick and a little more than three inches long. The flail rotated on this pin. The flail was held in place on the pin by a "rolled pin." A rolled pin is a common man's term for a pin made of steel that has been rolled into a pin shape. Some call these "spiral pins" and the true brand name is "Spirol" pin. Spirol being the name of the actual manufacturer of this device. So you can see where sprial and rolled come from.

You must have a "drift" to drive the pin out. A drift is nothing more than a round pin about three inches long and then tappered up into about a half inch round butt end. Drifts are bought by the size of the small end. In this case the end had to be 0.156 inches in diameter. That translates into a 3 MM drift. So I had to go get one of those.

After gaining access to the working area of the chipper, I found it configured with a short blade about 12 inches long. This blade was sharpened and was held into place by three bolts. One in the center and two out 2 inches from the center. It was meant to stay in its place, not move. Then comes the flail area. There are four flails, located at the cardinal points all 90 degrees from each other.

So material to be ground up enters the big red chute, and encounters the big sharpened blade first. After it gets passed the blade, it gets beatened to pieces by the flails. And the impeller assembly is turning so fast that all the material is expelled out a chute on to the ground.

Well one of the flails had thrown one of its three blades and that blade had hit other flails causing other flail arms to fail. This in turn caused the severe imbalance. I mean pieces of metal were flying all over the place, inside for few damanging seconds and then out the chute on to the ground.

After some Internet search, I found the parts, and I ordered them up. Got my drift and drove out the rolled pins - turned out to be a relatively easy job. That took about 10 minutes. Waited six days for the parts to come in. And then installed them. Had to drive the rolled pins back in through the flail into the pin and out the other side a little bit so that the pin was flush on both sides of the flail. Then we reassemble the chute with the help of my honey, she keeps me from cussing to much.

Fired up the red monster and we began make mulch again. We were grinding up oak leaves and small branches. We ran though one tank of gas and were half way through the next tank of gas when "bang" a flail finger shot out of the machine. Crap, same old problem again!

A little study and some belated thoughts and I concluded one of the flail mounts must be distorted or, so to speak, "bent out of shape." Not really misshapened so much as knocked off center so that the flail fingers were interfering with the structure. This was leading to premature failure of a finger that led to an interference with the remainging fingers (flails). As you can imagine, the interference happened once per revolution and let's say the assembly was turning 4,ooo thousand revolutions per minute. That is a lot of pounding and something has got to fail.

So the damn machine is on the patio waiting for me to tear it down again. This time I will have to "re-align" the flail mounts. This will not be a precise process, I do not possess welding machines or torches, so the tool will be a two pound hammer. Yep, I will have to beat it back to its original alignment. That means I have to figure out which one is the culprit and work on it, then reassemble the whole shebang and see if that fixes it. Poor man's trial and error method!

The assembly with flail mounts is called the impeller. A new impeller cost $233 plus shipping, so you can see why I am "aligning" the old one.

Bottom line is never, ever try to put a large rock or piece of concrete through a chipper/shredder. I know that no one would intentionally do that (yeah, right) but that is probably what happened to start this series of failures. Something very, very hard has had to knock the flail mount off its alignment. And the rest is history.

Beware of Damn Machines!