Barn Cleaner Drive Sprocket Bolts

[oldfarmall]

Hello-

Can anyone confirm what grade of bolts go in the drive sprocket for a barn cleaner? I have a 3 tooth sprocket that drives 240 feet of riveted flat chain (like Badger flat riveted/pintle Chain). The sprocket attaches to the hub with four 3/8" diameter bolts. I imagine these are supposed to shear if the load is too great and the sprocket just spins on the hub after the bolts shear? Grade 8 best to use? Thanks in advance!

-Jesse

 

[ET]

We used grade 5 in ours

 

[Bruce from Can.]

I use the same shear pins as we did in our small square baler. You want them hard enough so that they break off clean. And not give a bent or rivet type edge

 

[oldfarmall]

I use the same shear pins as we did in our small square baler. You want them hard enough so that they break off clean. And not give a bent or rivet type edge

Makes sense. I had a hell of a time removing the old bolts. Needed to heat with torch, then drive them out with a punch and hand maul from the bottom up. They didn't shear, just bent/deformed, which explains why they came out so hard. Must have been softer bolts? No marking in the head of the bolt that I could see.


I use grade 5 shear bolts in my small square baler. I have seen guys use grade 8 on the flywheel. Not sure which is correct? Grade 2 snapped too easy during normal baling.

Main reason I took it all apart was because 2 bolts were snapped off on bottom of the sprocket. Got the hub and sprocket removed yesterday. Cleaned and lubed up with anti seize. Going to pick up some new 3/8 shear bolts this week. Looking like grade 5 might be best. Thanks!