Beam style torque wrench

[Anonymous Poster]

I have been in the Automotive and heavy equipment repair business for thirty plus years and have been told many times that the beam type torque wrench was the most accurate. The clickers and break away's are good for when you cannot look at the scale while you are working with the wrench. So I guess I will have to agree with Hinomotomike

 

[Anonymous Poster]

I had my beam torque wrench checked for accuracy today. From 25 to 65 ft lbs it is right on the money. From 65 to 100 it reads slightly low. When my wrench reads 78 ft lbs it is actually 80 ft lbs. When it reads 95 it is actually 100 ft lbs.

I am pretty happy with the results. It is close enough for the work that I do.

 

[hazmat]

Glad to hear it. How much did the test cost?

 

[Anonymous Poster]

No cost... a friend of a friend did it for me. He is a Service Manager for a large automotive dealership.

John

 

[Trev]

</font><font color="blue" class="small">( Bob, there are instruments specifically for measuring the torque output of air impact wrenches. Of course, they cost over a thousand dollars. I think if you're concerned about torquing to a specified amount with your impact wrench, your best bet is a set of "torque sticks." You can get them various places, so Matco Tools is just one that you can look at and read about. )</font>

Thanks, Bird. I got myself a 80 ft/lb Torque Stick, but it came with no instructions. I'm kind of wondering.. what's the best technique? Leave your impact wrench at a high setting, then just hit the nut quick (say a second or two) with the Torque Stick? I presume if you just kept on hammering away, you'd exceed the 80 lbs, or the stick would break? Just a quick hit on it seems the most intuitive approach. Anyone had much experience with these things?

Thanks,
Bob

 

[Bird]

Bob, as many times as I've seen those sets of torque sticks on my brother's tool truck, I don't remember reading the instructions, so I'm not sure; maybe someone else knows better, but I think if you're looking at the end on the nut or bolt and run the impact wrench until the nut or bolt quits turning, you'll be right. On the instruments I know about for measuring the torque output of an impact wrench, you would normally give it 5 seconds, and I think that's what about what I'd do with the torque stick. Only a second or two will not let the impact reach it's nominal torque.

 

[bgott]

Watch the lug nut and you'll see when it quits turning. A lot of it rides on the torque of your impact wrench, I have a lower powered, older Craftsman and I would have to hit it longer than when I used one of the other mechanic's newer high powered impacts. Practice makes perfect, or at least gets you within an acceptable margin for error. /forums/images/graemlins/smile.gif You can break those torque sticks, we went through a few when I worked at Firestone. They flex and fatigue over a period of time but unless you have four different people using the same stick repeatedly day in and day out you shouldn't have a problem.

 

[LLove]

The instructions that come with "Torque Sticks", we have a set of 8 at work, is as follows...
"Set your impact wrench to 250 ft lbs of torque. Test the Torque of the Impact Wrench
with a known good Torque Wrench. Always use the Torque Sticks with the Impact Wrench
at this setting."
It also sayes to "Periodicaly check for proper torque".
They're NOT to be used for critical tightening such as Head bolts, Intake or Exhaust, & so on.
They are meant for wheel lugs and bolts, however they are not precise! The error is +/ - 2%.
If the spec's give a range of torque, say 85- 105' lbs, Then I use the stick rated at 90. When
the spec's give a single torque rating I use the Torque Wrench, not the Sticks.
Another factor not mentioned in the instructions is the Supply of Air. Both pressure and volume.
As pressure falls so does the output of the Impact. It also does the opposite as the air pressure
supply goes above 90psi.
A Regulator on the air line feeding the Impact nullifies this problem. Volume of air available to the
Impact is very important. Not enough = Weak output. No problem with Too much volume since
the "tool" will only consume what it needs.
In using the "Sticks"... Pull the Impact Wrench Trigger fully, (after you have it on the Lug), and
continue the tightening proceedure until you notice that the Socket end of the Stick is no longer turning.
Excessive Hammering will lead to Torque Stick Fatique/ Inaccuracies/ and Breakage.

Sorry for the long post, hope it helps! Lloyd

 

[Trev]

Thanks, everyone, for the help on the torque sticks! Sounds like it will work out fine..

Apreciate the replies!

Bob

 

[Bird]

</font><font color="blue" class="small">( Sorry for the long post )</font>

Nothing to be sorry for; that's the specific and detailed information wanted. Good post.