GREAT product design. I really like this tool. Comes with a nice blow molded, custom fitted, plastic case. The case has with what appears to be a substantial clamp. You can display torque readings in newton-meters(N-m), foot-pounds or inch-pounds. It uses one CR2032 coin battery and will auto shut-off after 60 seconds of no use.
I own 4 different mechanical torque wrenches (3x Precision Instruments and 1x Sears Craftsman). I estimate I have spent over $500 for these wrenches - including the occasional calibration. The cost to calibrate one of these wrenches can run from about $60 on up to almost $100. So, paying for just one calibration of a mechanical torque wrench costs more then buying one ARM602-4. Therefore, I believe his tool represents a great value. The published accuracy for the ARM602-4 is 2% in the CW direction. My best Precision Instruments torque wrench is 3%. The big disadvantage with the ARM602-4 is its size - it will not fit in similar tight places that a mechanical ratchet torque wrench can fit.
When I received my ARM602-4, I checked my other torque wrenches. I have a relatively new ( a couple of years old) Precision Instruments 1/2 inch split beam that agrees well my ARM602-4. But when I checked my old Sears Craftsman 3/8 inch, I found it was WAY off (but it has been almost 10 years since I had it calibrated). Yes, it is not evident which tool will have the most accurate torque measurement - but I think it safe to assume that a brand new ARM602-4 will have been recently tested for calibration.
I work as an engineer on new product development (but I spend my spare time wrenching). I believe the product design team hit it out-of-the-park on this design. Durability? I can not say yet - I have only had it about one month. But of course, I would not kick it around on the garage floor. But I do not kick my mechanical torque wrenches around either. With the twist grip style torque wrenches - if you drop them when the spring is not tight - you could knock them out of whack. And then you would be looking at a new calibration. Torque wrenches - including this tool - should be handled with much more care than any standard ratchet or wrench.
I have had nothing but problems with the click mechanism sticking on my Precision Instruments 3/8 inch wrench. EVEN after Precision Instrument "repaired" this wrench in 2014. So I appreciate the fact that the ARM602-4 does not have any mechanism that clicks and releases.
One thing I have learned, since I purchased this tool - is to SLOW down when attempting an accurate torque setting. This ARM602-4 can quickly capture a peak torque value. So if you quickly snap tighten your click style mechanical wrench you will see more of a difference in readings. I believe the difference can be explained by your technique and the fact that humans have a much slower response than electronics. By the time you feel the click and stop tightening your mechanical torque wrench - you can easily overshoot. So, I have learned to slow down - and I can now achieve much better agreement between a recently calibrated mechanical torque wrench and this electronic torque tool.
This has been a great purchase for me. I has me re-thinking the value of mechanical torque wrenches. If you do most of your torque settings where you have adequate clearance (like engine builds with the engine mounted to a stand or wheel lugs) the ARM602-4 maybe a better choice then buying one of the old, unreliable mechanical click style torque wrenches.
| Manufacturer | Durofix Inc. |
|---|---|
| Part Number | ARM602-4 |
| Item Weight | 7 ounces |
| Product Dimensions | 1.75 x 1.75 x 3 inches |
| Country of Origin | Taiwan |
| Item model number | ARM602-4 |
| Batteries | 2 CR2 batteries required. (included) |
| Is Discontinued By Manufacturer | No |
| Size | 1/2” (14.8 to 147.6 ft-lbs.) |
| Style | Adapter |
| Finish | Polished |
| Material | Plastic |
| Pattern | 1/2” (14.8 to 147.6 ft-lbs.) |
| Power Source | Air Powered |
| Torque | 147 Foot Pounds |
| Item Package Quantity | 1 |
| Head Style | Box End |
| Number of Handles | 1 |
| Measurement System | Metric |
| Display Style | LCD |
| Special Features | Lightweight |
| Included Components | Hard Shell Case, Digital Torque Adapter |
| Batteries Included? | Yes |
| Batteries Required? | Yes |
| Battery Cell Type | Lithium Manganese Dioxide |
| Warranty Description | 1 Year Limited Warranty |
