Torque Wrench Calibration at Tallahassee

Ken H.

Active member
Sep 9, 2000
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To all those who attempted to calibrate torque wrenches at GMCMI
Tallahassee with my Craftsman Calibrator: I've just finished retesting the
3 sets we attempted to use. With those devices, it is ESSENTIAL to match
the Load Cell with its own Display. Apparently I violated that rule when
we were testing.

What I found during my tests today, using a known accurate bending-beam
torque wrench, was that the Display I normally use, when connected to its
proper Load Cell, is "dead on". The other two, units, in their original
packages, when properly connected, proved to be inaccurate by about the
same percentages we saw at the rally. I've marked both of those as
"Inaccurate".

Sorry for the frustrations. Based on these results and what I remember of
our tests, I think most of your torque wrenches are reasonably accurate --
trust them instead of your "senses".

Ken H.
 
Ken:

Thanks for trying.

Just out of curiosity, how do the Harbor Freight torque wrenches fare from an accuracy standpoint?

I have a couple of Craftsman beam type that I use for applications that require accuracy. I had them tested with the Snap On guy about 15 years ago, and they were fairly accurate.

I know all generalizations are wrong including this one, but I would love to hear your observations on the HF (general 10 bucks) specials.

Dolph

DE AD0LF

Wheeling, West Virginia

1977 26’ ex-PalmBeach
Howell EFI & EBL, Reaction Arms, Manny Transmission

“The Aluminum and Fiberglass Mistress"

>
> To all those who attempted to calibrate torque wrenches at GMCMI
> Tallahassee with my Craftsman Calibrator: I've just finished retesting the
> 3 sets we attempted to use. With those devices, it is ESSENTIAL to match
> the Load Cell with its own Display. Apparently I violated that rule when
> we were testing.
>
> What I found during my tests today, using a known accurate bending-beam
> torque wrench, was that the Display I normally use, when connected to its
> proper Load Cell, is "dead on". The other two, units, in their original
> packages, when properly connected, proved to be inaccurate by about the
> same percentages we saw at the rally. I've marked both of those as
> "Inaccurate".
>
> Sorry for the frustrations. Based on these results and what I remember of
> our tests, I think most of your torque wrenches are reasonably accurate --
> trust them instead of your "senses".
>
> Ken H.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Dolph,

IIRC, there were a couple of HF wrenches tested and they showed similarly
erroneous readings to those of more expensive wrenches (such as at least
one Snap-On). With some trepidation based on limited data, I'd say the HF
wrenches do "pretty good".

Ken H.

On Sat, Apr 13, 2019 at 12:41 PM Dolph Santorine
wrote:

> Ken:
>
> Thanks for trying.
>
> Just out of curiosity, how do the Harbor Freight torque wrenches fare from
> an accuracy standpoint?
>
> I have a couple of Craftsman beam type that I use for applications that
> require accuracy. I had them tested with the Snap On guy about 15 years
> ago, and they were fairly accurate.
>
> I know all generalizations are wrong including this one, but I would love
> to hear your observations on the HF (general 10 bucks) specials.
>
>
> Dolph
>
> DE AD0LF
>
> Wheeling, West Virginia
>
> 1977 26’ ex-PalmBeach
> Howell EFI & EBL, Reaction Arms, Manny Transmission
>
> “The Aluminum and Fiberglass Mistress"
>
> On Apr 13, 2019, at 12:35 PM, Ken Henderson via Gmclist <

>
> To all those who attempted to calibrate torque wrenches at GMCMI
> Tallahassee with my Craftsman Calibrator: I've just finished retesting the
> 3 sets we attempted to use. With those devices, it is ESSENTIAL to match
> the Load Cell with its own Display. Apparently I violated that rule when
> we were testing.
>
> What I found during my tests today, using a known accurate bending-beam
> torque wrench, was that the Display I normally use, when connected to its
> proper Load Cell, is "dead on". The other two, units, in their original
> packages, when properly connected, proved to be inaccurate by about the
> same percentages we saw at the rally. I've marked both of those as
> "Inaccurate".
>
> Sorry for the frustrations. Based on these results and what I remember of
> our tests, I think most of your torque wrenches are reasonably accurate --
> trust them instead of your "senses".
>
> Ken H.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
>
 
One thing that is often overlooked with the click type torque wrenches is the need to unload the spring after use. This is done by returning the torque setting to zero or below prior to putting the torque wrench away. Leaving a preload on the spring for extended periods tends to push the wrench out of calibration. Where I dork, we have several thousand torque wrenches in use and have seen a good number of failure modes over the years. The most commons being weak springs.

If you are looking for the Cadillac of click-type torque wrenches, have a look at Stahwille. Since we started using them, our failures have dropped close to zero, and their ability to hold accuracy over their life-span is amazing. Be prepared to fork out a few $$ though.

Les Burt
Montreal
'75 Eleganza 26'

>
> Dolph,
>
> IIRC, there were a couple of HF wrenches tested and they showed similarly
> erroneous readings to those of more expensive wrenches (such as at least
> one Snap-On). With some trepidation based on limited data, I'd say the HF
> wrenches do "pretty good".
>
> Ken H.
>
> On Sat, Apr 13, 2019 at 12:41 PM Dolph Santorine

>
>> Ken:
>>
>> Thanks for trying.
>>
>> Just out of curiosity, how do the Harbor Freight torque wrenches fare from
>> an accuracy standpoint?
>>
>> I have a couple of Craftsman beam type that I use for applications that
>> require accuracy. I had them tested with the Snap On guy about 15 years
>> ago, and they were fairly accurate.
>>
>> I know all generalizations are wrong including this one, but I would love
>> to hear your observations on the HF (general 10 bucks) specials.
>>
>>
>> Dolph
>>
>> DE AD0LF
>>
>> Wheeling, West Virginia
>>
>> 1977 26’ ex-PalmBeach
>> Howell EFI & EBL, Reaction Arms, Manny Transmission
>>
>> “The Aluminum and Fiberglass Mistress"
>>
>> On Apr 13, 2019, at 12:35 PM, Ken Henderson via Gmclist <

>>
>> To all those who attempted to calibrate torque wrenches at GMCMI
>> Tallahassee with my Craftsman Calibrator: I've just finished retesting the
>> 3 sets we attempted to use. With those devices, it is ESSENTIAL to match
>> the Load Cell with its own Display. Apparently I violated that rule when
>> we were testing.
>>
>> What I found during my tests today, using a known accurate bending-beam
>> torque wrench, was that the Display I normally use, when connected to its
>> proper Load Cell, is "dead on". The other two, units, in their original
>> packages, when properly connected, proved to be inaccurate by about the
>> same percentages we saw at the rally. I've marked both of those as
>> "Inaccurate".
>>
>> Sorry for the frustrations. Based on these results and what I remember of
>> our tests, I think most of your torque wrenches are reasonably accurate --
>> trust them instead of your "senses".
>>
>> Ken H.
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>>
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org