I have three. Two are the direct read beam/pointer type, the third a
ratcheting adjustable. All three bought from Sears MANY years ago. I suspect
the beam type may be more accurate, depending on a couple of points, and
they are probably prone to maintaining their accuracy since there aren't
really any moving parts. The ratchet wrench and one of the beam wrenches are
150 lb/ft, the smaller beam wrench is 600 lb/in. I bought it originally just
to torque pressure plate to flywheel bolts. They're only 12 lb/ft, if I
remember correctly.
IIRC, at the time of purchase the ratchet wrench was around $35, the 150
beam wrench around $25, the smaller beam wrench around $20, but that was
some years ago, mid to late '70s. I bought the smaller one because I
remembered reading that all are most accurate in the middle of their rated
range, least so at the two extremes.
First point, make sure any beam/pointer wrench you buy has a floating handle
that pivots on a pin in the middle of the handle. This very simple concept,
I think originally patented by a company called Sturtevant (?), allows for
very accurate/repeatable results since the torque being applied, and the
readings, is always consistent. Secondly make sure the needle is always free
floating when tightening. It's easy to bind the needle on the scale if
you're not careful.
Snap-on used to sell a tester, for the expected "OH MY GOD!!" price, but
other than that I've not seen a rig to check the accuracy of the ratchet
wrench, but they're bound to be out there. I guess you could adjust the
wrench and tighten a bolt or nut and then use a beam type to see how much
torque it takes to move it. Theoretically the two numbers should match.
Might be able to rig up a deal with (probably) an electronic bathroom scale
and do some math, somewhat similar in concept to a valve spring tester, but
I'll leave that to the real engineer types. Have to think about that one for
a while.
My two 150 lb/ft wrenches seem to be pretty close. I keep them, along with a
couple of long breaker bars in their own drawer in my small roll around tool
chest. If they go in a tool box for "mobile" work each gets wrapped in a
thick towel. Am I paranoid? You bet!! ;>)
FWIW,
Ron
> This sounds like the "clicker" type, which I have. Does anyone have
> any experience with the type with the needle and scale ? which is more
> accurate? Durable?
>> I bought a 10-100 lb 3/8" drive SK torque wrench at toolwareouse.net
>> which I
>> find good for headbolts and most of the torquing on any car I won.
>>
>> I also have a 1/2" torque wrench that goes up to 150# that I use for
>> heavier
>> torquing such as crank pulley bolts.
>>
>> I also have a 1/4" drive that uses inch#s.
>>
>> Torque wrenches are generally not that accurate w/i 20% of their low
>> end or
>> high end of the scale.
>>
>> And remember to always zero out your wrench after use and don't drop
>> it and
>> DON'T loosen anything with it.
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