[AT] Adventures with shear pins

[Ralph Goff]

On 7/27/2014 8:07 AM, charlie hill wrote:
>
> I've been through a few other brush cutters since that one and I have
> never yet had a sheer bolt to sheer when I hit something regardless of
> having a slip clutch or not.  In fact I've hit stuff so hard with that old
> D-10
> that with the engine running at wide open throttle it shut off dead in it's
> tracks,  Sheer pin never budged.  Not even the brass ones.
>
> The best thing I've found is the slip clutch but they didn't have them back
> in the
> old days or at least I didn't know about them until the 80's.   The only
> trouble
> with slip clutches is that if you set them loose enough to do any good they
> tend
> to slip when you don't want them too.  It gets down to how much risk to your
> equipment you are willing to absorb in order to get maximum production.
>
> Charlie
>
>
Sounds like your shear pin was working loose. We had that a lot on 
square balers. A new shear pin would seem to "stretch" and work itself 
loose after a few bales. Finally we started using double lock nuts on 
the shear pin and it did make a difference. Those balers just used a 
common 5/16 or was it 3/8 bolt. My newer NH 847 round baler takes a 
rather odd sized shear pin on the gear box and I have not found a right 
sized substitute other than the original NH parts. Luckily it does not 
break many shear pins.

Ralph in Sask.