Shear bolts -- possibly older terminology

[VistanTN]

My "new to me" but very old IH Model 46 baler has several shear bolts. The operator's manual (a reprint) talks about type 1 (regular), type 2, and type 3 (special) bolts and says use type 2. The picture shows a bolt head with three hash marks that I would call a grade 5 bolt. Is this correct? I don't want to put in a grade 5 if it is too hard and will cause the machine to be damaged, but the normal cap screw (grade 2) would be a mistake if it is too soft. Figured if anybody anywhere can tell me, you all can.

VistanTN
Time for second cut haying ...

 

[tf116]

a grade 5 bolt will have 3 slash marks and a grade 8 will have 6....that is what I've been taught......the grade 2 and softer bolts do not have any slash marks...
Mike

 

[CharlieTR]

ASTM A449 Specification - Portland Bolt

You might try calling these guys or it seems like they have a chat page.
This link gives some specs you might compare to the grade 2 and 5 on another web page. It seems that the markings on the bolt would indicate gr 5. (three bars) Does ASTM show up anywhere in the book?

 

[jwcinpk]

I have a IH McCormick model 46 also and I have never had any problem with the Tractor Supply Company cheap bolts. I buy them by the pound. I believe they are grade 5. I've run it like that for about 6 years now and over 10000 square bales.
Just go to TSC and tell them you want a low grade bolt that will shear and they'll point you in the right direction.

 

[VistanTN]

TSC carries grades 2,5, and 8 with 2 being weakest and cheapest. If you've had no problem with those, that's a safe way to go. I was just confused by what the manual called "type 2" in several places and then the companion illustrations that showed what I was taught was a Grade 5 (add two to the number of hash marks). I guess since most commonly you can only find grades 2, 5, and 8 that could be what they are calling type 1, 2, and 3.

Thanks for the responses.
VistanTN