Shear bolt on rotary cutter

[CMV]

Just wondering....what does it take to break one? I have a 5' TSC light duty rotary cutter - the angled back one they sell for $1200. It's taken a lot of saplings over its rated 1", lots of softball sized rocks, chunks of dead wood, and just yesterday a concrete cap block - the ones that are about 1/2 the width of a typical cinder block but solid.

So far, it just keeps going and set real low, giving me a pretty nice cut. Looks like field was cut with a lawn mower other than how longer clippings lay after being cut.

Anyway, is it more a matter of time or X # of hitting things you shouldn't? I'm still on the original factory one - didn't do anything like replace with a grade 8 fastener or something. Other than the terrible racket or seeing a big rock dart across the ground, doesn't seem like it cares about hitting these things.

Have a spare 4-pack of grade 2 shear bolts in the toolbox, just haven't needed yet and kind of thought I would by now...

 

[prichard]

I've been surprised at not breaking a shear on mine as well. We had a forestry mulcher clear the land when we bought it and there are occasional larger chunks of wood (logs) I hit but it keeps going.

 

[oosik]

I've never used a rotary cutter. But for about 18 years I cleared my driveway with a snow blower. I could usually figure one, possibly two, blown shear bolts - the first time I cleared the driveway. The cause was invariably a chunk of wood that would get stuck in the blower somewhere. Rocks, chunks of ice and mice never seemed to bother it at all.

 

[Sawyer Rob]

First thing I'd do, is to see that it has the RIGHT bolt in it in the first place. IF it does, then I'd not worry about it.

Back in the day, before I ran rotary cutters with clutches, I sheared bolts regularly and got SICK of having to deal with shear bolts, so I won't have a cutter without a clutch these days!

SR

 

[MESSMAKER]

I mow commercially so I use a mower more than usual and in some tough places. I may go a month and not shear a pin or I might shear 3 in one week. It is usually a rock or stump that gets me. It takes 5 min to change one. I use a 1/2 inch standard bolt 4 inches long.