www.mcmaster.com

Get the right stuff. If you choose the military grade stainless, it will most likely be more than enough. 

On Jul 8, 2011, at 12:14 AM, Rocket J Squirrel wrote:

> Hi all (jumping the gun a bit on that Friday thing  . . . )
> 
> I bought a Hi Lift jack from Al "Pensioner" Knoll earlier this year.
> It's a vintage piece. Very cool.
> 
> I just went to refresh the critical parts on the jack with ones from Hi
> Lift's jack rebuild kit, but the shear bolt and the climbing pins in the
> kit don't fit.
> 
> Puzzled, I contacted Hi Lift and described what I was looking at and the
> fellow there said that the jack was made prior to 1960 (!) and they
> don't have parts for it.
> 
> While the original climbing pins are in good shape, the original shear
> bolt is bent a bit. Needs replacing. I asked Hi Lift what grade of bolt
> I could use there and the nice man wrote back to say:
> 
> "I�ve been a couple of days trying to get you an answer, but with little
> success.  Our shear bolts are specially made and heat treated for us.
> The Rockwell hardness scale on these bolts ranges from B85-95, with most
> testing to B89-90.  I�ve been trying to find out what bolt that compares
> to but have failed to find any comparison."
> 
> So I looked at some charts this morning and, if using tensile strength
> is any indication, this Rockwell hardness translates to something like
> 88,000 psi. Grade 2 bolts come in at around 74,000 and Grade 3 (a
> rarity, I think) are more like 110,000. It's a 1/4'' bolt.
> 
> Did I count on my fingers and toes good enough?
> 
> The fellow went on to add that,
> 
> "I know my dad would break his shear bolt and just stick another bolt
> into it, but that is not a recommended safe practice.  I wish I could
> just send you a shear bolt, but we�ve checked and don�t have any laying
> around after all of these years."
> 
> Fair enough.
> 
> So I got four choices here: re-assemble the jack and sell it on
> craigslist with a caveat and buy a new jack, re-assemble this one with
> the deformed shear bolt and see if it holds when I need it (not so
> smart), or bang in some Grade 1 or 2 bolt* from the hardware store
> (unknown degree of smartness).
> 
> Ideas?
> 
> =============
> * There does not seem to be any way to determine whether a bolt is Grade
> 1 or 2, as neither have marks on the head. So what's my Ace Hardware
> store gonna stock? It is a mystery!
> 
> --
> Rocky J Squirrel (Jack Elliott)