When will the clutch slip?

[bigtiller]

I have a new 5' rotary cutter for my jd 2720. The RC has a slip clutch rather than a shear pin. With the RC blades free to swing out of the way when hitting an obstacle, when will the clutch ever slip?

 

[mddorange]

It will and most of the time you won't even notice. About the only time you will notice is when it starts to bog down the tractor but doesn't stop it.

 

[HEC]

Just keep it adjusted properly and it will do it's job .

 

[geneP]

Just because the blades swing back doesn't mean the cutter doesn't take a shock when the blades hit something solid. If it is adjusted correctly, the clutch will slip a little to absorb the shock and you might never know it. Mine usually has noticeable slip when I get the stump jumper hung up on one of the many low-cut stumps I bush hog over trying to keep weeds and brush out of my cut-over land so maybe grass can get a start. When the blade completely stops I can hear the clutch squeal. I quickly raise the cutter to clear it.

 

[bumperm]

Oh, it'll slip. When rotating, centrifugal force has those "free swinging" blades appear to the tractor as solid. That is, until they hit something even more solid that's enough to overcome the considerable centrifugal force working to keep the blades extended. By allowing the blades to pivot on such impact, less stress is imposed on the gearbox and drive line. Pivot blades will have shear bolts lasting longer and slip clutches sliping less. But shear bolts will still shear and the slip clutch will still slip when need be.

Shear bolts are cheap and about as idiot proof as can be, except they can be defeated through the use of too high strength bolts. Slip clutches are more expensive and arguably less id'jut proof - - you do have to remember to unstick the clutch before first use after it's been sitting awhile (loosen bolts, turn free, re-adjust clutch bolts) otherwise the slip clutch may not unstick until damage occurs elsewhere.

 

[bigtiller]

Oh, it'll slip. When rotating, centrifugal force has those "free swinging" blades appear to the tractor as solid. That is, until they hit something even more solid that's enough to overcome the considerable centrifugal force working to keep the blades extended. By allowing the blades to pivot on such impact, less stress is imposed on the gearbox and drive line. Pivot blades will have shear bolts lasting longer and slip clutches sliping less. But shear bolts will still shear and the slip clutch will still slip when need be.

Ok, that makes since, i never figured centrifugal force into my thinking. I have never used a rotary cutter so i am looking forward to this new mowing experience.