Best torque wrench/screw driver

[Samsonite801]

Edit to add, I use a regular driver for other connections but that Capri will mentioned looks really nice and may be on my list (you can never have to many tools)...

I have a special technique for screwdrivers and nut drivers, where it involves your grip, and using a controlled slippage method (up to proper torque), as I'm approaching proper screw torque, I am gripping onto the screwdriver handle with only a certain level of tension (as I am turning it in), and when the screw arrives at proper torque, the screwdriver starts to slip on my palm grip, and I keep trying to turn it each time and the palm just slips more and more until I get total slippage on every turn attempt. Then I know it is at right torque. The actual torque spec depends on how much controlled slippage you allow. I'd say it's both grip tension and heart intuition (mind/body/spirit/soul synergy).

WARNING:
Please do not try this at home unless you understand the technique well, until you can know that you can get same torque as with a special screwdriver. It took me since I was 10 years old through now, to learn the technique described here.

 

[JoshuaD]

I use the Capri tools torque screwdriver and it works well, but I have not used competitors products so hard for me to fully recommend. Does it job well so far. Would love to see what everyone else is using.

Great, thanks!

 

[MarkSolar]

I like the torque drive adapters, I can use whichever handle I already own that fits best, and it doesn't take up much space in the tool box.

 

[robbob2112]

I love all the old torque wrenches, but from several years in the Navy spent working in the calibration shop I can tell you they do wear out and go out of calibration.

The snap type work by a spring against a block mounted to touch the head just before the pivot point. If the springs get any corrosion or just plain get old they can weaken and throw off the reading. The blocks start out with sharp edges and slightly rounded corners on them, the corners wear down.

Maybe 10% of to torque wrenches that came in needed adjusting. There is typically an adjustment screw under the cap/handle at the hand end of the wrench where you can tighten or loosen the spring tension. If you take out the pin near the head the blocks can be replaced.

Calibrating a wrench consisted of putting it on a measurement jig and testing it at three positions in the range of the wrench. 1/4, 1/2, and 3/4. At each position your lowered it and tested 3 times. It had to snap within a few percentage points each time and had to be consistent. If it was non-linear you could sometimes stretch the spring a bit and retry. We kept a pre-expended bin full of new springs and blocks for those that failed.

The biggest issue that causes failures with a torque wrench is not storing it with the tension completly off the spring. I know it is a pain, but unwind it just past the minimum when you store it and never drop it.

The other issue is dropping it. When you drop it and it lands its blocks and springs smack each other really hard and can shead fragments because they are hardened steel and are brittle rather than ductile. The fragments can jam up the works or if the fragment is off a corner it can throw off the readings and make it inconsistent.

Usage - don't tighten a bolt to the correct torque and then come back later and "Check it" ... when you "check" it you are tightening it and overdoing it.

My 2 cents and what it is worth.

 

[robbob2112]

A bit more - the older style beam torque wrenches - you know the long handle with a pointer sticking out. Made up of a beam and pointer shaft.

Those were more stable over time but once they started to drift the only choice was to replace them. Sometimes people bent the pointer shaft to make it read correctly then tagged it 'only for use clockwise'. Then short cycle the calibration interval. This was generally frowned upon but it happened frequently if the squadron insisted they had to have it back today to get some work done. The replacement percentage on them being out of calibration and unable to be bent a little was only about 1%. They would drift from simple metal fatigue

If they needed to be replaced it meant switching to the spring and block type. The planes these were used on were the A7 and the F/A-18 and in some cases that specific type was called out in the manual. This was around 1990ish when they were still switching over from the A7 to the F/A-18

But, they were also more easily damaged. The tips got bent and the pointer shafts got snagged on things. They also were damaged more easily if dropped. If they were not kept in a nice carved out drawer that fit the tool the 'servey and replace with like item' rate was around 50%.

One more tidbit I am going to add after watching a video, when using any sort of torque wrench you want it straight on the bolt/nut and if you are using an extension you can hold that to steady things, but holding the head of the spring an block sort of torque wrench is a no-no. It can throw off the reading, probably not a lot but a bit. And when threading into aluminum all it sometimes takes to strip things is a little bit.

My 2 cents and what it is worth

 

[Bluedog225]

It’s a little hard to find a torque screwdriver that goes below 10 inch-lbs.