Introduction: How to Properly Use a Torque Wrench
Video tutorial on how to use a torque wrench. There are a few different styles of torque wrenches, but for this video I will be using a click type which is probably the most common. Other types include a beam type, dial, digital, slipper, and, no hub. In the video, I have both an inch pounds torque wrench and foot pounds torque wrench. Torque wrenches are available in certain torque spans which is why you may need more than one. Here I have a 3/8” drive inch pound torque wrench that goes from 50 to 250 inch pounds. Inch pounds are a finer increment than foot pounds. Next I have a 1/2” drive foot pound torque wrench that has a range of 30 to 150 foot pounds. A torque wrench is a very precise piece of equipment, therefore four tips you should know about ownership is never drop them, do not use them as a johnson bar to loosening tight fasteners, always keep them clean, and return the scale to it’s lowest torque range.
Now to set the torque wrench, they should have some form of a lock which needs to be disengages, then rotate. This vehicle which is a 1998 Ford Ranger, the wheel torque spec values is 100 foot pounds. Rotate the handle and then line it up on the scale correctly. We will have larger increments on the barrel scale, so there will be 10 foot pounds in between each number. To setup the single value increments, the scale around the handle is needed for that. Align the number line on the handle with the center line on the barrel, so considering this is 100 foot pounds, the handle number line will be zero. If it were 105 foot pounds, then align it to 5. Next ensure the lock has been applied, otherwise you do risk adjusting the setting when torquing a fastener. Use one hand to hold the pivot in place, then the other on the handle. Rotate the torque wrench until the it clicks, you should be able to hear, feel and see the click. As soon as that click activates, immediately stop turning . One click is all that’s needed, otherwise you do risk over tightening the fastener.
Moving onto another example using the inch pounds torque wrench. Again this is the same principle, this too has a lock which needed to be pulled back, rotate the handle to the correctly value, and then release which will automatically lock into place. For this each of the bolts need to be torqued to 20 foot pounds. The inch pound torque wrench does not read in foot pounds, so a simple conversion is needed. 1 foot is equal to 12 inches, therefore 20 multiplied by 12 is 240. Just as an example I will set this to 230 inch pounds, therefore the 0 will need to be aligned on the handled. When setting the torque valve to 240 inch pound, therefore we will need to be past the 230 mark and align the handle to the 10th increment. Place on hand on the pivot point and the other on the handle, then rotate until you hear the click, again only one click is needed. When done with the torque wrench, position the scale back in it’s lowest position. Otherwise this will jeopardize the accuracy of the torque values.