Rotary Cutter Shear pin?

[the old grind]

Depends on what you mean by 'regular'.

The plainest unmarked-head cheap grade 2, not grade 5 with the '3-spoke' head marking, unless you're hard on 'em & want to push the limit of 'ok'. (its done a lot within reason)

They're sized/intended to give way comfortably shy of breaking something else between PTO and turf. I have 'em & break 'em on & only when using the slasher, usually if too high rpm, too low to ground, too quickly releasing the clutch, or a combination of them .. clumsy operating. ("Hello it's me, .." )

But grade 2s are cheap by the pound at TSC. I use jam nuts when I install vs tighten against a hub.

 

[MHarryE]

Hate to steer you wrong but most use grade 5 or 8 for shear bolts. Grade 2 are very ductile material and tend to smear when they break. Grade 5s and harder fracture clean and are easy to remove. They also tend to specify shear bolts of a size so the solid portion is in the shear area meaning no threads at the shear point. Gives a more consistent value at fracture.

 

[WranglerX]

Most most common bolts in use are grade 2, grade 5 and grade 8... Other grades exist but usually for "special" applications...

SAE Grade 2 - 74,000 psi, low carbon steel (no spokes on head)...
SAE Grade 5 - 120,000 psi, medium carbon heat treated steel (3 spokes on head)..
SAE Grade 8 - 150,000 psi, medium carbon alloy steel (6 spokes on head) ...

Dale

 

[NoTrespassing]

I actually bought a package of King Cutter shear bolts/lock washers/nuts. They're grade 2. Probably cost a dollar or two extra but it was easier than buying individual parts and they were packaged nicely.

Kevin

 

[PILOON]

Hate to steer you wrong but most use grade 5 or 8 for shear bolts. Grade 2 are very ductile material and tend to smear when they break. Grade 5s and harder fracture clean and are easy to remove. They also tend to specify shear bolts of a size so the solid portion is in the shear area meaning no threads at the shear point. Gives a more consistent value at fracture.

I agree with this as well.
Soft will elongate and damage the holes while grade 5 will shear nice and clean.
IMHO 5 is nice and should still protect the equipment all while shearing clean.

It was mentioned that often the holes grow bigger over time and that was probably due to damaged aligning holes from soft bolts.

My experience is mainly from snow blowers. (and most use grade 5)