Torque calibration

[Hunter7]

Per the B 2601 manual, I have torqued the loader frame M14 bolts to 108 lbs/ft. The manual says to repeat every 30 hours. A couple of the spring lock washers sprung. The dealership mechanic said this is not something he sees. He suggested my Dewalt torque wrench may be off. However, he has never re-calibrated his torque wrench either. I found a service to re-calibrate the instrument, but that service costs about the same as just getting a new one, about $100 with shipping. The Dewalt torque wrench is kept in its case, never dropped, and returned to “0” after every use. While the web has videos on do it yourself calibration, I can’t find instructions for adjusting this particular tool. There is no obvious adjustment screw. My local rental place rents a torque wrench for $30 a day, but admits they don’t have it calibrated. Questions: is it worth paying for re-calibration? What is the easiest, most reliable torque wrench for just one tractor? Do most people simply do “good n tight.”? Should I just buy a new torque wrench every couple years?

I used to work in the medical field. We tested and calibrated measurement instruments on a regular schedule. This is so different. Is calibration just for companies doing machine tools? Do most dealers calibrate their torque wrenches?

 

[mcfarmall]

I work in the Pharmaceutical industry. You're working on a tractor. Replace the junk lockwashers and tighten the bolt until the water comes out.

 

[xrocketengineer]

No that it is the best practice but I have an old Craftsman 150lb-ft beam torque wrench that I hardly ever use. There is not much calibration that can go on that one. Then I take my other cheapo click type torque wrenches and put on a 15mm socket and connect the two torque wrenches together. I set the click type torque wrench to 20, 30, 40 or whatever value and apply the torque and when it clicks, I check the reading on the beam wrench. At least that gives me a warm tummy feeling that the torque wrenches are not completely out of whack.

 

[lynnmor]

The old and simple beam style torque wrenches stay accurate for a very long time. I connect a beam style to a click wrench and see if the clicker clicks when it gets to the test setting. That is good enough for me. If the clicker needs adjustment, there are videos for various brands.

 

[Flintknapper]

Per the B 2601 manual, I have torqued the loader frame M14 bolts to 108 lbs/ft. The manual says to repeat every 30 hours. A couple of the spring lock washers sprung. The dealership mechanic said this is not something he sees. He suggested my Dewalt torque wrench may be off. However, he has never re-calibrated his torque wrench either. I found a service to re-calibrate the instrument, but that service costs about the same as just getting a new one, about $100 with shipping. The Dewalt torque wrench is kept in its case, never dropped, and returned to “0” after every use. While the web has videos on do it yourself calibration, I can’t find instructions for adjusting this particular tool. There is no obvious adjustment screw. My local rental place rents a torque wrench for $30 a day, but admits they don’t have it calibrated. Questions: is it worth paying for re-calibration? What is the easiest, most reliable torque wrench for just one tractor? Do most people simply do “good n tight.”? Should I just buy a new torque wrench every couple years?

I used to work in the medical field. We tested and calibrated measurement instruments on a regular schedule. This is so different. Is calibration just for companies doing machine tools? Do most dealers calibrate their torque wrenches?

Junk Washer IMO. Replace.

Your torque wrench is not THAT far off that you torqued the bolt to 'yield' and it twisted the lock washer.

Some bolts/fasteners should be torqued to 'spec' (lug nuts, engine components, etc). Many others can just be tightened to the German Standard of "Gutentite". Its a tractor.

 

[Pawnee]

I have done what the rocket engine guy does. You can do it with 2 click wrenches as well. They will both click at the same time if they agree. It's uncanny how close the clicks are.

I have also built a "Calibrator".
Say you want to calibrate at 100 ft Lbs.
Put a big bolt through the middle of a 10 foot 2x4 and set it on something so it can rotate freely enough.
Hang 20 Lbs on one end 5' out.
Set your torque wrench to 100 ft Lbs and start to lift the weight by torquing the big bolt.
It should click when you get it horizontal.

I've never done it with 100 ft Lbs but I have with lower values and have never found either of my 2 quite good wrenches much out of spec. They get put away in the case at a low setting just like you do.

I don't worry about it anymore.

 

[cthomas]

The snap-on tool truck sometimes has a torque checker tool. Yes I have spent the hundred bucks to calibrate my torque wrenches.

 

[The Evil Twin]

Some stuff I worry about how calibrated my torque wrench is- BMW con rods, crank bearing caps, engine cases....stuff that is torque to yield.
Most stuff the important thing is that they are torqued evenly- head studs, wheels, clutch plates.
Whatchu got there is a need to replace a washer. If your wrench was that far off the scope you would be snapping bolts on stuff.

 

[cthomas]

I did the calibrations on mine when I was doing a few valve bodies a week and didn't want a leak, in the Traverse/Acadia's transmissions. Always get a kick out of some engineers bright idea sucks in the real world. I have heard that Germany engineers must be a technician for 2 years in their respective field. I hate split spring washers just for this reason, replaced a few with concave washers/blue lock-tite.

 

[number two]

Angle Repair Service in Beckley,WV is the go-to place for torque wrench calibration and repair.
Good Vendor!
Check them out online.
Good Luck!

 

[radas]

+1 for the beam style torque wrenches. I have a precision instruments (they make snap on and IIRC HF's Icon wrench) and it's been excellent for tractor use.

Also, yes, replace the lock washer with a grade 8 or 10 from the hardware store and move on. Was there a washer under that lock washer?

 

[ferguson]

I do the same as xrocket Have two old / old beam ones 3/8 inch LB & 1/2 foot LB marked Grumman Aviation. Checked them back in the eirly 80's when i worked at a Mack dealier in NY They were right on then. Have no reason to believe there off now. Have had to adjust the Stanley click one my son has. Also any thing on the threads will change the torque put on the "bolt". IE oil, never Seize, lock tight.