Date: Fri, 3 Jul 1998 10:40:38 EDT
Reply-To: Scooter061@AOL.COM
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: Scott DeSanti <Scooter061@AOL.COM>
Subject: Re: question for an engineer
Content-type: text/plain; charset=US-ASCII
In a message dated 98-07-02 23:55:01 EDT, you write:
" I picked up a used torque wrench a couple years ago that I'd like one of you
smart engineers to learn me about, if you can. It's rather small as these
things go, maybe 16", reads in Nm's(up to 70) and inch-pounds(up to 600)
only.
Has a circular scale that swivels to read either of the above. It was
manufactured by Consolidated Devices, Inc. (City of Industry, Ca). The model
#
is 6002 DI. There is what appears to be a military stock # (if you know what
that is) of 5120-00-288-8865, and it and the date of manufacture are stamped
one above the other on it towards the end where the socket fits on. Now, my
????'s are these:"
Hi Jason,
As a military electronics technician, believe it or not, I deal with
these things on a daily basis. Lemme take a wag at answering your questions.
" Is there a way to find out if it's accurate, without paying through the
nose?"
There sure is. Just look in the yellow pages under "Laboratories-
Testing". If there isn't a measurement and test lab listed call one of the
listings and ask them where they get their devices tested.
"Can foot-lbs be converted to inch lbs, and vice-versa, by simply
multiplying/dividing by 12? I don't think they can, but I'm not sure. Can
you splain this in moron terms so I can understand it?"
Believe it or not, you are exactly correct. 600 inch pounds would equate
to 50 foot pounds. Not a great deal of torque but adequate for small
fasteners. Ideally, a torque wrench should have a max range of twice the
torque required for the task. This places the setting used at the
midrange...the most accurate range on the wrench.
" If I can have it calibrated, will it stay that way for a considerable amount
of time, or will I have to have it done on a regular basis?"
That all depends on how much use it gets and how careful you are with it.
According to Air Force maintenance practices, torque wrenches are calibrated
every 90 to 180 days. But this is because of their high frequency of use.
Personal use would probably only require yearly cal at the most.
Additionally, anytime a torque wrench is dropped or severly jarred it should
be recalibrated.
" I know a torque wrench is important, as are properly torqued nuts and bolts,
but I'm too cheap to sink big bucks into a good, full-sized one if I don't
have to."
Gee, if a Bently manual costs 60+ bucks, what's another 50 or 60 to get a
decent torque wrench to really do the job right? Just my .02. Hope this
helps some. Happy Fourth of July.
Scott De Santi