[rebel-builders] Torque wrench
Posted: Sun Feb 19, 2012 6:31 pm
There are a lot of sources. Automotive, Aviation, Snap-on, Proto, Mac,
Craftsman, etc. What do you want to torque?
I have a Snap-on 0" to 200"/lb clicker type with the quarter inch drive that
I use for most of my work (A/P, IA, Titan Rocket engine builder) prior to
retirement.
I also have a Proto 100" - 1500"/lb 3/8" drive clicker that I use for the
higher values. These meet most of my needs.
I also have some much bigger and much smaller ones for specialty
requirements. On a Slick magneto the "P" lead is about 20"/lb you will
brake the ceramic insulator of the capacitor if you do it by hand to what
you feel is tight. On some Rocket engine components I have applied 600
foot/lb to the mounts.
Another type of Tq Wrench is the bending arm with a pointer, or a Dial. Now
days I believe they make digital versions.
When a torque of drag plus specific torque is called out, I always used a
dial to get the drag of each nut, then add that amount and continue to the
called out value + drag.
Calibration: At the Rocket factory we had purchased about 25 new wrenches
at one time, we sent them to our cal. Lab., 5 of them were rejected as
outside of our 5% requirement. Another tid-bit, we did not use a tq wr in
the bottom 20% of it's range, so if it was a 200"/lb we did not use it at
less than 40"/lb. I believe that is a good policy myself, because most were
not accurate in that range when we did our required daily tests. Yes this
may have been over kill but in several hundred pay-load launches our engines
never caused a failure to place a satellite in proper orbit.
SO be aware, not all torque wrenches are calibrated equal. Another thing if
one is dropped!!! God forbid the Dog knocked it on the hard cement
floor...It SHOULDE BE re-checked.
The FAA wants to have you have them calibrated each 2 years. Of course we
are building Experimental Airplanes so if a wrench is out of calibration it
shouldn't matter...right.
At a big shop that, I once operated the single engine department, WELL the
multi eng guys installed a prop on a 421C and pulled 2 of the studs out of a
prop before the mechanic questioned if it was a bad prop, or his torque
wrench. Needless to say ALL torque wrenches, company and personal, went out
for calibration. About 20% needed repair or retirement. We also added a
torque meter for daily checks.
Dick Wampach SR-108 N331RW
-----Original Message-----
From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf Of Kelly
M. Ewing
Sent: Thursday, August 05, 2010 11:49 AM
Subject: [rebel-builders] Torque wrench
Good afternoon all, anyone know where to get a decent torque wrench? I know
spruce has them, just want another source.
Thanks
Kelly ( Moose )
Canada
kelly@tru-form.ca
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Craftsman, etc. What do you want to torque?
I have a Snap-on 0" to 200"/lb clicker type with the quarter inch drive that
I use for most of my work (A/P, IA, Titan Rocket engine builder) prior to
retirement.
I also have a Proto 100" - 1500"/lb 3/8" drive clicker that I use for the
higher values. These meet most of my needs.
I also have some much bigger and much smaller ones for specialty
requirements. On a Slick magneto the "P" lead is about 20"/lb you will
brake the ceramic insulator of the capacitor if you do it by hand to what
you feel is tight. On some Rocket engine components I have applied 600
foot/lb to the mounts.
Another type of Tq Wrench is the bending arm with a pointer, or a Dial. Now
days I believe they make digital versions.
When a torque of drag plus specific torque is called out, I always used a
dial to get the drag of each nut, then add that amount and continue to the
called out value + drag.
Calibration: At the Rocket factory we had purchased about 25 new wrenches
at one time, we sent them to our cal. Lab., 5 of them were rejected as
outside of our 5% requirement. Another tid-bit, we did not use a tq wr in
the bottom 20% of it's range, so if it was a 200"/lb we did not use it at
less than 40"/lb. I believe that is a good policy myself, because most were
not accurate in that range when we did our required daily tests. Yes this
may have been over kill but in several hundred pay-load launches our engines
never caused a failure to place a satellite in proper orbit.
SO be aware, not all torque wrenches are calibrated equal. Another thing if
one is dropped!!! God forbid the Dog knocked it on the hard cement
floor...It SHOULDE BE re-checked.
The FAA wants to have you have them calibrated each 2 years. Of course we
are building Experimental Airplanes so if a wrench is out of calibration it
shouldn't matter...right.
At a big shop that, I once operated the single engine department, WELL the
multi eng guys installed a prop on a 421C and pulled 2 of the studs out of a
prop before the mechanic questioned if it was a bad prop, or his torque
wrench. Needless to say ALL torque wrenches, company and personal, went out
for calibration. About 20% needed repair or retirement. We also added a
torque meter for daily checks.
Dick Wampach SR-108 N331RW
-----Original Message-----
From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf Of Kelly
M. Ewing
Sent: Thursday, August 05, 2010 11:49 AM
Subject: [rebel-builders] Torque wrench
Good afternoon all, anyone know where to get a decent torque wrench? I know
spruce has them, just want another source.
Thanks
Kelly ( Moose )
Canada
kelly@tru-form.ca
-----------------------------------------------------------------
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Unsubscribe: rebel-builders-unsubscribe@dcsol.com
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