Torque wrench basic information

[pwuser161228146379]

In this video I showed you guys how to use torque wrench, Learn to use and maintain Torque Wrench properly. Using Torque Wrench on nuts and bolts is important to make sure that the bolt is tightened to the correct tightness of torque. Local mechanics don't care. It can ruin your Car. Always make sure that the nut or bolt is tightened to the correct torque. Make sure nut or bolt is not lose or overtighten. I shared everything I knew about Torque wrench.

The price of this Torque Wrench is Rs.5500 and it easily available in Pakistan.

[Xulfiqar]

Have you tested the accuracy of these?

[pwuser161228146379]

No it was having Calibration certificate so I didn't tested the accuracy. Also I don't know how to test and do the calibration for it. If you know how to do let me know.

[Xulfiqar]

A rough way to check is to use a beam and weights, basic physics

Btw

Torque wrenches need to be handled like glass and reset when not in use. Meaning zero them out and treat them like glass when not in use.

Also one needs to understand friction, drag and stiction torque when tightening a bolt. Meaning if the spec calls for an unoiled clean thread and you have an oiled nut/bolt, you need to clean it or reduce the torque.

Torque wrenches are most accurate in the midrange of their scale. E.g. if you need to tighten a screw to 8lb/ft its better to use a in/lb (small) one (5-140 in/lb scale) and set it to 96 in/lb rather than use a medium one and set it to 8 lb/ft (5-100 lb/ft scale)

[pwuser161228146379]

Yes I reset it when not in use so that there is no load on spring. Its a big size torque wrench so I only use it for wheel nuts which are unoiled and clean but If I use it for engine in future I will remember to clean it or reduce torque.

But my torque wrench don't have in/lb unit of measure. And I was using this big size torque wrench for small bolts with low torque specs and I stripped the treads of bolt hole after that I only use this big torque wrench for 30 lb/ft to 150 lb/ft.

[teknokid1]

Hm, so it would be better to own 2 torque wrenches, a small and large one? The torque spec difference between say lug nuts and spark plugs is quite a lot.

[Xulfiqar]

Yes

You need two, one tiny one for the very small ranges of 1-14 lb/ft -these are sold as in/lb torque wrenches (10 kay bolt aka m6 bolts n nuts)

And one regular one for other work. (12 ke bolt aka m8 and above)

[Xulfiqar]

As i said you need to use the torque wrench so the range you are using is in middle of scale.

Btw how were you tightening low torque items with a large wrench?

[pwuser161228146379]

I cleaned the spark plugs and when I was fitting coils I thought to tight the coil bolts to 10 lb/ft ( Chrisfix ban-nay ka shouq tha first ) I tighten them with hand then I used torque wrench and the bolt was like free while tightening with torque wrench because it is large torque wrench so it is not that much sensitive and the force I applied was to much because of its long handle. And after turning it few times I told my dad that I think I damaged the bolt threads and when I removed the bolt the hole where the bolt fits was stripped. Then I went to mechanic , he used tap and die tool and now 12mm bolt is installed.

[Xulfiqar]

You had a wrench that could measure 10!lb/ft?

Btw pencil coil bolts are 8lb/ft on all toyotas, this has been revised about 5 years ago.

Btw by 12mm bolt im assuming 12mm head which means an M8 bolt.

Your mechanic is crazy for doing that as Im sure he had to remove the spigot bushing from the coil too. A helicoil or bushing repair is much better, stop visiting moron workshops

[VCheng]

My shoulder pops at exactly 50 ft-lbs.

(I have other calibrated joints too to cover all ranges.)

[pwuser161228146379]

But I think helicoil is not available in Pakistan. I am sharing pictures of my torque wrench on box its written that 30-150 lb/ft but we can set torque wrench to 10 lb/ft.

[Xulfiqar]

This wrench is trash, on spec they are writing 30-150!lb/ft usable range and then printing 10 on the scale.

This automatically means the calibration cert that comes with it is good for “raddi” also.

This is why I asked that if you tested it. And also said to use a torque wrench where the required force is in the middle of the usable scale.

Please buy quality instruments, not the cheapest trash. And btw helicoil is sold in Karachi at least, its slightly expensive but worth it, and a lot of machinists can make a brass insert too that can restore the original threads for light torque like a pencil coil bolt.

[nfssaad]

for helicoil contact them

http://www.naaspak.com/products/helicoil.html

[pwuser161228146379]

I will test and check if its correct or not. And I think only these are available in Pakistan but I will check in Market.

[Xulfiqar]

You can buy high quality click type torque wrenches too in Pakistan, they cost a lot of money too - e.g. any decent one will be about 100 USD at minimum no matter if you are in USA or Pakistan.

If you are crafty enough you can use a simple ratchet, a pull scale and some basic math in your head.

If you find some old tool sellers, you maybe able to find old torqo-meters or scale type wrenches but be careful with them, you can overtighten any bolt easily if the coefficient of friction is upset (heat, thread type, stretch etc etc, the torque should be applied in one smooth motion and then stopped and left alone).

[VCheng]

the torque should be applied in one smooth motion and then stopped and left alone

... unless tightening in steps as specified, or by degrees of rotation as specified.

[Xulfiqar]

Even then, the torque is done in one motion, not gently creeping the wrench,

If the spec says 30 lb/ft then 70 lb/ft

You have to smoothly pull the wrench till it clicks at 30

For the 70, you again smoothly pull the wrench

Same for angle tightening, best to do in one equal smooth pull.

[VCheng]

Ah, I now see what you meant.