Torque Wrench Shopping Dos and Don'ts
If you're the kind of person who has a keen hand for DIY repair activities, then you must have a complete set of tools to work with on your garage. A must-have tool for any auto repair job is a torque wrench. This will allow you to tighten up those loose bolts and nuts to the appropriate foot-pounds setting. If you're thinking about getting yourself one, then here's a guide to help you out.
- Purchase an accurate torque wrench. Look for one that is rated less than ?5% accurate in its foot-pound settings.
- If you're on a budget and want something really inexpensive, there are available torque wrenches that have a ?2% inaccuracy.
- Look for LED or digital torque wrenches since they are more accurate.
- Consider how often you'll be using the torque wrench.
- Buy a torque wrench that's made in America. Wrenches made from this country are mostly the ones that have the highest quality.
- Choose one with a good warranty. There are even torque wrenches that come with lifetime warranties.
- Don't sacrifice quality over fancy tools. It's better and more practical to purchase a durable and well-made torque wrench that is cheaper but can be just as accurate as expensive ones.
- If you're not a serious mechanic, don't shell out cash for really expensive ones. Save yourself some money and purchase one that's for about $80 or less.
- Don't purchase from salvage yards. Although you'll be able to save more, it would still be better if you purchase from a reputable brand.
With these dos and don'ts, you now have an idea on what kind of torque wrench you should buy. Always consider where you're going to use it. If you're really an expert mechanic, then it's good to invest in a professional wrench. But if it's just for home and garage use, then save some money and find a cheaper one with qualities similar to a special torque wrench.
Putting the Torque Back to the Wrench
The torque wrench is very helpful when you need to tighten a screw or bolt that requires a specific value. If you need to use this wrench, but then you discovered that it has worn out, then there really is no need for you to panic. You can easily repair the torque wrench just by following these steps.
Difficulty level: easy
What you'll need:
- Small flathead screwdriver
- Torque calibration machine
- New end cap
Step 1: Check the accuracy of the wrench using the calibration machine. The widely accepted standards are the ISO 6789 Hand Torque Tools Requirements and Test Methods (International Organization for Standardization) and the ASME B107.14 Hand Torque Tools (American Society of Mechanical Engineers). You must complete both tests because these two are slightly different.
Step 2: Set the wrench at 100 percent and operate it three times on the calibration tester to test the ASME method at 100 percent. Then, reset the wrench to 20 percent and do the procedure again. Test it at 60 percent and back to 100 percent. Take note of the accuracy discrepancy with each of the three tests.
Step 3: Complete the ISO version of the same accuracy test but perform the same sequence at the same settings five times per setting instead of three times. Don't recalibrate should the readings be within five or six percent of the accuracy requirements. If they are beyond the accuracy parameter, recalibrate it to sufficiently bring them back to accuracy range.
Step 4: Recalibrate for minor adjustment by setting the wrench knob at 20 percent of full scale. Taking a small flathead screwdriver, pry off the end cap/plug and remove it from the end of the knob. Test the wrench at 20 percent level and turn the handle clockwise to increase, and the other way around to decrease the reading to be able to adjust it.
Step 5: Insert the T-shaped hex into the T-shaped slot on the wrench knob and loosen the setscrew enough to enable you to work with the knob. Carefully, pull out the knob and twist it to set the 0 at the 20 percent mark on the scale. The marks should be exactly aligned. After, tighten the setscrew back down.
Step 6: Take out the scale bezel on the wrench's handle by using a 1⁄16 hex. Simply use your fingertip to reset the scale of the lowest increment line even with the lowest increment. Put back the bezel and inspect the readings at the test settings of 20, 60, and 100 percent. Put the new replacement plug into the end of the wrench.
- If the wrench refuses to turn, check the spherical ball placement of the secondary cam, which is found in the business end of the wrench.
- If these adjustments do not work, a more detailed calibration is required.