Date: Fri, 8 Jul 2011 11:19:18 -0700
Reply-To: Rocket J Squirrel <camping.elliott@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Rocket J Squirrel <camping.elliott@GMAIL.COM>
Subject: Re: [Friday] Bolts -- Rockwell hardness translate tograde?
In-Reply-To: <426920C23F7643A29F8130149CDD3369@JimArnottPC>
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Hi Jim,
I was feeling a bit irritated this morning by some kneejerk responses to
my technical question and took it out on you. My apologies for my
surliness.
But it's probably good idea to avoid mentioning here that you jacked up
a house because the same folk that got the vapors when I mentioned the
word "jack" (with no mention of "van" or "vehicle" or "climbing under")
are probably popping a whole lot of Valiums right about now.)
As the guy who works for Hi Lift told me, his dad, like you, used to pop
in any old bolt when one broke. Not that he recommended doing that, of
course. I mean, I do things here that I would never tell my customers to
do. Liability, surprise calls from lawyers of freshly-widowed women,
that sort of thing . . .
Grade 1 and 2 bolts most likely have less shear strength than the OEM's
no-longer-obtainable spec'ced bolt and that's the direction I'd like to
err in. Using a harder bolt, as others have pointed out (and using your
excellent fuse analogy), would be like replacing a 10 amp fuse with a
100 amp fuse. Not such a smart idea. It's the shear bolt we want to see
snap, not a chain or tree saver strap or loop on the van.
In the current version of the Hi Lift jack (mine's pre-1960 so no
telling about its specs) the shear bolt, AKA "safety pin," is designed
to fail if the load exceeds 7,000 lbs (3175 kg). A person with an ME
degree and a poor sense of how to spend his time could probably figure
out what a Grade 2 bolt would shear at. It's probably still higher than
what I need to haul Mellow Yellow's a** out of sand.
-- RJS
On Fri, 2011-07-08 at 10:01 -0700, Jim Arnott wrote:
> Sorry Rocky, that wasn’t my intention at all. The bottom line is the
> bottom line. Aircraft Spruce is where you’ll find something close to
> what you need. Me? I’d plunk any old bolt in there and continue on.
> (But then I’ve so overloaded a Hi-Lift that I had to replace the lift
> pins. We jacked up a house....)
>
> Jim
>
> From: Rocket J Squirrel
> Sent: Friday, July 08, 2011 8:30 AM
> To: Jim Arnott
> Cc: vanagon@gerry.vanagon.com
> Subject: Re: [VANAGON] [Friday] Bolts -- Rockwell hardness translate
> tograde?
>
>
> Hey there Jim,
>
> I appreciate the answer but it feels as though you are lecturing me.
> Maybe I'm misreading it.
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