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Originally Posted by Ronzi
'But, the best is still the old Beam Type...'
Interesting. Do you mean the type that has a graduated plate with a pointer??
Many years ago when I bought my first torque wrench I went to the Snap On shop and asked for one of those. The guy behind the counter sneered and said "We sell torque wrenches, not guessers."
I was effectively put in my place and ultimately bought a Snap On 150 lb/ft dial type wrench for $65, a pretty good pile of money for a torque wrench in those days.
As for $5,000 for a torque wrench, a hell of a lot of engines have been rebuilt using wrenches that cost a lot less then that. A commercial rebuilding shop might be able to justify such a device, but I bet the reason for using it has more to do with repeatibility and durability over thousands of operations than strictly accuracy.
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Hi,
A Beam Type wrench uses
Physics as opposed to
Engineering in the mechanical Dial or Click Type. It is the most accurate, but does require the user to properly read the scale, which is where the guessing you mentioned comes into play. There are many things which can fail in the mechanical types which the Beam is immune to, it relies on simple, known deflection.
In truth, there are so many variables, including the ambeient temperature, whether or not you're using an extension, etc. that Accuracy is really more of a concept than a reality. But, the Beam Type has fewer variables which must be correct to achieve an
accurate torque.
With better machining tolerances in today's manufacturing, the trend is to rely less on a Torque Value in favor of a Torque Angle Value. This takes into account the material used, the size and pitch of the threads and results in a tighter tolerance when torquing a Fastener. A Torque Angle Meter is a simple tool similar in simplicity to a Beam Type Wrench. You use a Torque Wrench to achieve maybe 3/4 of the spec and then continue to rotate the Fastener an additional specified Angle to achieve the proper tightening...
Happy Motoring!... Jim'99