Shear Pins

[sixdogs]

A shear pin is just a bolt and usually a grade 2 with no markings on the head. Some things use a grade 5 and are identified by three marks on the head. Just check the owner's manual and buy bolts at the local farm store in the bulk bin.

 

[Deere Dude]

I am all for saving a buck, but if you need to buy bolts from the bulk bit you probably have other issues like rocks or ice that need to be dealt with.

 

[bigtiller]

That's got to be frustrating! But the OP has a JD 54" snow blower which requires a grade 5, 1/4" bolt for a shear pin.

Well shucks, that's the second time today I forgot to ad my pic.

 

[Code54]

A shear pin is just a bolt and usually a grade 2 with no markings on the head. Some things use a grade 5 and are identified by three marks on the head. Just check the owner's manual and buy bolts at the local farm store in the bulk bin.

100% agree - I grabbed a handful several years ago and still have 1/2 left - doubt I spent $5 on the whole bag of them from Rural King

 

[SPYDERLK]

Magnum
Shear pins are there to take the "hit" so something else doesn't break that may be more expensive than shear pins. Your decision as to what to use.
If shearing too many pins, find out what is causing this to happen and remedy that problem.
I like to use lock nuts on the bolts and do not tighten the bolts, but leave them loose.

I always snug em up. Not very tight, but I figure the slight elastic stretch relieves the shear zone as it is cut in two.

 

[bigtiller]

I always snug em up. Not very tight, but I figure the slight elastic stretch relieves the shear zone as it is cut in two.

I do the same, and I also add a drop of blue lock-tight. They last for a very long time this way.

 

[PILOON]

What I found is that 'hardware store grade' bolts stretch and distort B4 they shear while a grade 5 makes a nice clean break.
The trick is to not have a thread in the shear area as that is a built in fault so to speak.
I don't torque up tight, just snug and always use a nylon lock nut.

The softer bolts once sheared are hard to drive out while a grade 5 will simply pop out easily with the outers usually long gone and it is simply a bit tricky to align the holes to press out the captive shaft remnant (that is on the augers) an my fan I never find either halves, LOL. (I have a gravel drive)

Oh, I located a manual at one time and the factory actually did call for grade 5.

 

[sixdogs]

Manufacturers have gotten a little more snarky lately and recently I have seen two things with grade 10.9 metric socket head cap screws (bolts) as hear bolts that are hard to find if not bought from a dealer. Most hardware store metric socket head cap screws are grade 12.9 so to be true to the equipment you almost have to buy from the dealer and the price is many times as much as hardware, even though it's the same thing. It's OK but I was able to find some grade 10.9 on EBAY.

I'm not sure but I think 10.9 is similar to grade 2 in that it's not heat treated while grade 12.9 is likely the same as grade 5 with mild heat treating. it's kind of a mystery.

 

[oosik]

Well - I thought ASTM grade10.9 was equal to SAE grade 8. Looked at my torque tables and now I'm not so sure. Have to see if there is a cross-reference table somewhere.

 

[CobyRupert]

If you're ever stuck them you can use s regular bolt with a nut but don't tighten it too much.

Make sure the bolt is slightly of a smaller diameter. It helps..

Now while everyone will say get shear pins etc, a regular bolt doesn't have much strength and will shear pretty easily off.. if not easier than some shear pins.

But like I said, if ever the store is closed and you're midwork.. a regular bolt can save the day.

"..a regular bolt"?
"Make sure (it's) of a smaller diameter"?

Don't take this the wrong way, but this is some of the worst advice I've ever read on the internet.