Rotary Cutter Bent Rotary Cutter Blade

[Cityboyfarmer]

I'm getting pretty good at tearing stuff up. I bent one of my rotary cutter blades when it caught on a pine log while driving through a dip. The leverage was enough to bend the blade down.

 

[Cityboyfarmer]

The photo in the post above has the new blade and the bent blade side by side for comparison.

Here is another shot looking at the ends of the blades.

 

[hudr]

Wow, last time I did that kind of damage to a blade, I wound up also replacing the output shaft on the gearbox. I hope the blade was the only casualty.

 

[Cityboyfarmer]

Its actually only 1-1/2" bend, but with the off-set blades it really caused serious vibration. The gear box and shaft are OK. I ran it after I put the blade on. Nice & smooth now.

 

[sweettractors]

<font color="blue"> Here is another shot looking at the ends of the blades. </font>

It is very unusual for JD to have a blade that will bend. You would think the slip clutch or shearpin would have prevented this from happening. Are you sure the blades were made from the correct material and heat treated correctly?--Ken Sweet

 

[Keith_B]

We bent a blade like that recently on the bush hog. It was a new blade and was way too soft.

 

[RonMar]

Was the mower spun up when this happened? I could see some sort of a twist if you really locked it up while running, but not this sort of straight down bend. I would also imagine if it hit something that serious, as mentioned above, the pin or clutch would have given way before a swinging blade would bend.

 

[Cityboyfarmer]

It was kind of a freak incident. I'm not exactly sure, but here is how I believe it happened. I was cutting an area that is sloped and has dips, stumps, and some pine beetle damaged tree sections about 6" in diamater on the ground. I think one of the pine logs got wedged between the rear tire, the blade and the deck. I heard the racket, then smelled the slip clutch. I raised the cutter and the blades began rotating again, but the cutter was vibrating real hard. I disengaged the PTO and I could see one blade was lower than the other from the seat of the tractor. I think the blade was bent as I lifted the cutter and the wedged pine log, not from striking the log. Or the blade could have lodged in a stump and bent as I raised the cutter. There was a pine stump in the vicinity with a big chunk taken out of it.

Anyway, I replaced the bent blade and ran the cutter for an hour yesterday and it ran smoothly. So I survived this one with just a $25 blade.

 

[hobbyfarm]

Funny,
He doesn't even mention all that scratched paint! /forums/images/graemlins/grin.gif

 

[Indydirtfarmer]

Is it possible that the blade was "hooked" on the stump, and bent when you raised the mower? I've wedged logs between the blade and upper deck on mowers more times than my nerves care to recall. Never bent a blade yet. Usually the slip clutch takes care of that. In spite of the easy availability of brush mowing equipment, it sure isn't always for the faint of heart.....