Combines Rotor Balance

[cutter2388]

The rotor drive hub bushings could be out of it. I have had this in the past and it has a pretty bad vibration what only gets worse.

 

[Ed_Boysun]

I've wondered about the whole rotor balancing thing too. What you are doing when you add weights when the rotor is in the machine is "static balancing". It seems to me that one end of the rotor could be a pound heavy at 12 o'clock on the drive end and the other end could be a pound heavy at 6 o'clock and it would be perfectly balanced at rest. When you start to run it at speed, however the drive end would vibrate one way and the discharge end would vibrate the other way. I think that this would lead to twisting and bending forces on the rotor and consequently undue stresses on bearings and also vibration. If you notice the computer type tire balancing machines put differing amounts of weight at different places on each side of the tire to affect a "dynamic balance". Fortunately a few of the shops in my area have installed computer balancers for rotors that should take care of this and let an old worrier like me rest a little easier. Ed in MT

 

[John_W]

Years ago on a tour of the CIH combine plant I saw them balance rotors on a special machine that spins the rotor and tells them where to put the weights and how much weight it needs. Took the guy about a minute to balance a rotor. They said at that time that they would re-balance any rotor for free if you bring it to them. How far are you from East Moline IllinoisIJ

 

[rtnKY]

I am about 400 miles plus I have to take the rotor out. What I am concerned about is if the rotor runs smooth within the range that I operate will there be a problemIJ

 

[Trevor]

I agree with Ed, the rotor may appear to be balanced, but highly unlikly that it is balanced properly. When you see a rotor dynamicly balanced you will understand that it is next to impossible to balance in the machine. Check around the Machine shops, there is likly one close that can to this kind of work. Pulling the rotor sounds like a difficult chore, but is a simple job, can be done in about a hour with two people. Trevor

 

[steve_farmer]

I'm in Minnesota and last fall a guy from Minneapolis, Kansas came through the area balancing rotors,choppers,fans,etc. right on the combine. He did my chopper and it worked great for $175.

 

[Ohio__Steve]

There is a shop locally that will cut a 6 in. hole in rotors to get in and remove dirt accumulation.This dust seems to harden with condensation moisture unevenly and fairly permanently to put the rotor out of balance...after careful clean out the piece is wire welded back in place, any other holers repaired and rotors run smoothly again...is done in machine and has worked well on the machines I know about

 

[thrasher]

This last comment is exactly the problem we had. If you hook up to the front of the rotor and pull ahead about three feet you can see the bushings which will cause a bad vibration and "out of balance feeling" when in operation. Also, a lot of dirt and debris gets caught under the triangle shaped mounting areas for the rotor bars up and down the rotor.

 

[Redfever]

There is a way you can statically balance your rotor. First take out the middle separating grate so you can get to the rotor. Run machine(rotor) to get it warmed up and really free to turn. Shut off everything and shift rotor drive gear box in to neutral. Turn rotor by hand and notice if it stops at the same place every time. Mark the bottom and rotate bottom to top. Find a piece of scrap metal to bolt on behind a rasp bar if specialty rotor or a separation bar if standard and bolt it on the bottom. Trial and error is the idea here as to how much weight and exact placement.It can be done just use patience and common sense.

 

[turbored]

Go to a farm supply store and buy some cow magnets and use them to balance your rotor. You can move them around easily and when you find the right amount of weight, take it off, weigh it, cut your piece to weld on and get it a few ounces lighter and weld it on! Good luck!