Re: wheel torquing, air guns, and litigation (rated:pg13)

[MSV96@aol.com]

In a message dated 7/9/98 Shane East (seast@home.com) writes:

<< I noticed the mechanic attaching the wheels with
an air gun, so I politely asked him to hand torque them instead. He showed me
some attachments that looked like nothing more than various lengths and
diameters of iron, that supposedly limit the torque the air gun can deliver. I
convinced myself that I understood while thinking " how the heck does that
work?". He never did re- torque by hand, incidentally. Was I bamboozled? It
seems plausible a torque limiting device could be attached to an air gun, but
I would expect it to be more clutch or gear like in its design. >>

There are indeed very good torque limiters for air tools. We use them in our
manufacturing line where I work (Mountz tools I believe). I see no reason why
what works for little screws with inch/pound torque specs can't be applied to
bigger tools.

I too have seen the tool you describe used by a tire shop (Parnelli Jones
Tires) and they explained to me that it is indeed a "torque wrench" (but
certainly NOT "hand torqued"!).

<< BTW, I photographed (what I do) a lawyer who successfully sued a wheel
manufacturer that didn't have torque specs on the wheel. His client's wife was
killed when an over- torqued wheel cracked, flew off a nearby car, and flew
through their window. Their argument was if tire manufactures print inflation
specs on the side walls, wheels should have torque specs. >>

One has to consider who the end user of the instructions is. Anyone operating
the car can add air at the local filling station--thus max pressure is on the
sidewall (which almost certainly differs from recommended pressure). Changing
the wheel is described in the owner's manual and includes the torque spec.
While it can be argued that "anyone can figure it out" this is not a routine
thing done at every fill-up.

FWIW, it is also a matter of competance by the repair facility. Last time I
bought tahrs from Sears (flame on but I got Dunlop D60A2's for the ovlov
"mommiewagon" for less than mail order there) I was told that their policy is
to always "hand torque" now (prolly part of the fall out from Sears Auto
Centers getting fried by the press for their crappy work). Indeed...on their
work order is the torque spec that is pulled up by their 'puter from a
database. Now if they really do as they say is another story...

Mike Veglia
87 5kcstq