Zero Turn 42 blade bolt and washer

[HKJ]

Had a blade come lose today while getting up leaves. Thought I tightened it and it was still lose. Inspected bolt and ran it in without blade. No problem. I noticed the washer did not look exactly flat. Like it was slightly concave. I turned the washer over and the blade became tight. I talked with the dealer who sold it to me who is also a friend. I think he thinks I am crazy. Has anyone seen this?

 

[bertsmobile1]

Three types of spring washers
Std Split
Star for use on soft or thin material
Cupped for applying even pressure
And many blades go on with a cupped washer

 

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I had the same problem with aftermarket blades - they were too thin - - I got the thicker blades - new washers [ convex] and all is well.