Torque wrenches

[Keith2305]

I have a craftsman 1/2" 25-150 lb torque wrench that has served me well. It was around 70$ made in us. Anyway what I wanted to add is for any of the clicker type torque wrenches I've read to always back them off to 0 after each use. Makes sense that leaving it in the tool box set to 100 would compress the spring over time.

 

[paulfun9]

I had a surplus WW2 Snapon 'blade type' that calibrated just fine after spending over 50 years in various tool boxes.

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Funny how the simple blade style just works time after time without any problems but the expensive clicker type always seem to get out of adjustment. My oldest blade style still works perfect and every time I had it tested it was spot on but every single one of my click style wrenches has been off each year I had them tested and I don't even use them as much. So much for advancement give me the old style any day!

 

[Keith2305]

I agree that the blade style is probably going to stay accurate longer but I always wondered how much of a pain they are to read doing something like torquing 150 lb lug nuts? When you're trying to exert all that force and have your eyes lined up with the gauge?

 

[Spindifferent]

From Lowes:

Shop Kobalt 1/2-in Drive Click 50-ft-lbs - 250-ft-lbs Torque Wrench at Lowes.com

Works well, I have this and the smaller 3/8-in drive. Happy with both.

 

[newbury]

Yeah my bad on the first link. Meant more like what Jim suggested. My rear disk to hub bolts are supposed to be 406 lb/ft. Similar numbers in the 400s for some of the loader bolts (cap screws). I guess I'm looking at a second wrench for those?

For one time/rare use I do the math. My rear disk bolts require 400 lbs plus. I put my 200 lb son on a 2' breaker bar.
The 450 lb torque wrenches are EXPENSIVE.

I agree that the blade style is probably going to stay accurate longer but I always wondered how much of a pain they are to read doing something like torquing 150 lb lug nuts? When you're trying to exert all that force and have your eyes lined up with the gauge?

That's where leverage comes into play, assuming you have the room. Put 4' of pipe on the handle and get someone else to read it. The handle of the wrench doesn't measure the torque, the head does.

Calibration is critical in the airline and manufacturing industry. I don't think if I'm off 10% on tightening most of the exterior bolts on my tractor equipment it will fall out of the sky.

 

[paulfun9]

I agree that the blade style is probably going to stay accurate longer but I always wondered how much of a pain they are to read doing something like torquing 150 lb lug nuts? When you're trying to exert all that force and have your eyes lined up with the gauge?

Sometimes you just have no choice but to use a big click style wrench but for most of my needs I can use one of my multipliers and get up to 300 FT LBS at the nut with one hand. For many things tractor related I still use the old fashioned way of the BIG bar over the big breaker bar till the feel is about right to my weight. As pointed out I have no fear of falling out of the sky when running my tractor. When it comes to things like Gland nuts on a flywheel that must be over 300 FT LBS I am picky and use the multipliers.

 

[kebo]

bsvitale:
Torque wrenches are not a buy it, and use forever wrench.
They must be calibrated periodically.
There is no hard rule for how often this is necessary, but it IS necessary if you want accurately torqued fasteners.
Some say every 6 months, but that seems excessive, and probably applies only if you are using the tool every day, for 6 months.
Some say to re-calibrate after 2500 uses. For most of us that too would be never occur.
The real story here is that the settings for a new wrench, when compared to a wrench that has been used, or sitting in an unheated building, or has been dropped, may be very different.

Good information! I will also add some more pointers that I learned in a torque class at work taught by an instructor from a tech college in Tennessee. He was affiliated with Snap-On and of course, all the equipment he brought to class was Snap-On brand.

1) Torque wrenches should always be stored with it set to its lowest setting. Typically, that is "0", but some wrenches don't go down to "0".

2) Torque wrenches have a tolerance, some of the better ones (more $$$) are pretty low, down to about the +/- 3% range. The lower priced units can have a tolerance range as much as +/- 10%. So, keep that in mind.

3) A wrench should be sized appropriately. For example, if you have a nut that should be torqued to 148 ft lbs, don't use a wrench that only goes up to 150 ft lbs. You can do that, but it's not going to you accurate pulls on a consistent basis. You need to use a wrench that has an upper working upper limit that is at least 10% above the highest setting you will use it for. Example, for a 150 ft lb wrench, don't use it for pulls above 135 ft lbs. Likewise, the same holds true on the lower end of a wrenches working range.

4) As bsvitale stated above, if you drop a torque wrench, all bets are off and it should be recalibrated before being used again.

5) For a good pull, use a slow, steady, and firm action to get the wrench to click. Don't jerk it! Never check a nut that has been torqued!!! In other words, don't click the same nut again AFTER YOU JUST TORQUED IT. I know the urge to do that is irresistible, but that WILL result in an over-torqued condition! You must have faith in your tools to do it right the first time.

6) Nuts that have been torqued once should NOT be used again. I know this one gets ignored 99% of the time, but that's what we were told. There is a reason for that and it has to do with the nut and or bolt being stretched after it has been torqued once.

So there you go, my company paid a lot of money for that information (which is just some of the high points), but you are getting it for free and you are welcome to use all or none of it. :thumbsup:

 

[crazyal]

Kebo, #6 iis not a hard and fast rule. If it was you would be replacing lug nuts and studs every time you remove a wheel.

400 ft/lbs is not something you are going to do easily. My T wrench goes to 250 ft/lbs and just doing 200 is pretty hard. You should also learn how to correctly use it. For one thing you can't put one of your hands on the ratchet area of the wrench to help keep the socket on the bolt/ nut. If you have an air compressor and a good impact wrench you can buy torque sticks. But to get in the 400 ft/lb area you will probably need a 1" impact wrench.

 

[Wagtail]

Ta for that, kebo. I was not aware of much of what you wrote.

In fact, as per #1, I went out to my shed and backed my wrench to '0' as you suggested. It makes sense.

 

[kebo]

Kebo, #6 iis not a hard and fast rule. If it was you would be replacing lug nuts and studs every time you remove a wheel.

400 ft/lbs is not something you are going to do easily. My T wrench goes to 250 ft/lbs and just doing 200 is pretty hard. You should also learn how to correctly use it. For one thing you can't put one of your hands on the ratchet area of the wrench to help keep the socket on the bolt/ nut. If you have an air compressor and a good impact wrench you can buy torque sticks. But to get in the 400 ft/lb area you will probably need a 1" impact wrench.

I agree with what you are saying crazyal, and even said in my post that this rule gets ignored 99% of the time. I was just stating what we were taught in the class, you can use your own best judgment. I am guessing the heavy equipment, the aerospace industry and probably the nuclear power industry (and some others likely) are the ones that follow that rule.

Another option for high torque settings is to use a torque multiplier, like was suggested by a previous poster.