Sharpened my blades, now the tractor is vibrating.

[Snatchface]

Did I screw up? I am not the worlds's most mechanically saavy person. I removed the mower blades and sharpened them up with a dremel. Reattached them. Torqued them in as hard as I could. Now when I start up the blades the tractor vibrates and sounds generally awful...not smooth as it did before. I know the blades are on in the correct orientation - I even mowed with it for 1/2 hour and it works fine. Any ideas? Is there some trick I am unaware of?

BTW - it's an old Husquvarna LTH140.

 

[KirkMcD]

Did you rebalance them after sharpening?

 

[Snatchface]

Rebalance? Eh? I suddenly have that feeling that I did something wrong... You think I really could have taken off enough to unbalance the blades?

 

[rebelmedic]

Yes,it is possible to take enough off a blade to unbalance one.A simple way I balance mine is to drive a nail into a post or shed at near 90 degree angle.Place the center bolt hole of blade over the nail far enough out so as not to touch the post.The blade will rotate to the heaviest side.You then grind a little at time off the heavy side till balanced

 

[Snatchface]

That advise is very much appreciated. Thank you.

 

[beenthere]

Did you rotate the blades (turn them around) after you re-attached them to see if they were operating in the same plane? Maybe you didn't have them correctly seated on the spindle. Unless you ground a lot off in re-sharpening, I too doubt you un-balanced them enough to notice a lot of vibration. But there is something wrong. Best to explore and do the balance thing just to make sure, as well as find the cause. I wouldn't continue mowing.

Also, tight is good enough. Beyond tight just makes it tough to get them off the next time. /forums/images/graemlins/wink.gif

 

[thcri]

Nail in the post is the easiest way. This is how I do it also and you can get it pretty close.

murph

 

[Bird]

I balance blades the same way as the other guys, except I use a very small, round shaft screwdriver held in my hand instead of driving a nail into a post. And I'd certainly check that if I were you, but I also agree with the post by beenthere; quite possible that there's another problem as he said.

 

[normde2001]

Well said, beenthere. It takes a lot of grinding with a Dremel tool to get a blade out of balance enough to notice.

 

[gotrocks]

I've goofed reinstalling blades before. The threaded part of the shaft was a little smaller that the part of the shaft that actually went into the hole in the blade.
I put the blade on and the washer then tighten the nut, but the blade was caught on the shoulder where the size changed. Boy did it jump, didn't take long to stop and find the problem. Now I am always aware of that when changing blades.