This month PMM reviewer Tony Powell gets to grips with Sealey’s 3/8 in. SQ drive digital torque wrench, model no. STW 308.
The wrench arrived in a glossy cardboard sleeve which waxed lyrical about the tool’s capabilities. Beneath this flashy exterior lay the sturdy black-blown plastic case which held the torque wrench itself. Opening the case revealed a very nice-looking wrench with a shiny chrome reversible ratchet head and a very comfortable feeling grey plastic handle.
As with many tools I was initially disappointed due to the lack of batteries, but this disappointment soon proved misplaced, as on further inspection I found them hiding under the paperwork in the bottom of the case. Paperwork, it should be noted, which included a relevant calibration certificate.
Getting started
Installing the batteries was simple and quick, you just unscrew the base and pop them in, a quick press of the red button and the wrench sprung into life. Initially setting the wrench without reading the instructions as most of us seem to do was very simple and I was also very pleased to note that once set, the wrench remembered the setting for next time: a good time saver for me as I do hundreds of bolts with the same settings and having to set and unset each time becomes quite a bind (winding off the tension on the spring on my mechanical torque wrench reduces wear and keeps it in calibration for much longer). Not a problem with a digital wrench though. Once I read the instructions I found that it can actually remember several different torque settings even when turned off and back on, most useful if using the same settings repeatedly.
This particular wrench operates from 8 to 85 newton-metres but can also read in lb.in, lb.ft, or kgf.m. I should add here that wrenches with higher limits are available in the same range.
Once set, the wrench will vibrate and emit an audible alarm once the preset-limit is reached and the scale has an LCD readout with LED backlight. I also noticed that at a simple flick of a switch on the ratchet head the wrench can be used to discover how tight bolts are when undoing them or when using a left-hand thread, of course.
This size wrench is ideally suited to smaller nuts and bolts as found in many vehicles these days including the likes of spark plugs, which need to be torque-tightened to ensure they are located in the correct orientation to ensure an efficient burn of the fuel mixture, injector clamping bolts and use on lawnmowers and motorbikes etc. With a length of 34 cm or just over 13 inches and a good solid feel it looks and feels the part.
Reaching the limit Sealey has covered all the bases by using a vibrate, audible beep and a warning light when the set limit is approached and met. So if you’re working in a loud environment you still know the limit is reached. I’ll admit that a part of me does miss the old-fashioned clunk made by mechanical wrenches and in my opinion, the beep could be louder!
In use, the wrench has proven to be a very helpful tool saving me quite a bit of time in winding on and off to release the spring pressure as I have to do with my old wrench.
The wrench itself is comfortable to use and although solid feeling, it’s not too heavy and doesn’t cause any fatigue in use. Plus, it’s small enough for use in the engine bay without difficulty.
The verdict?
Certainly a very nice, easily operated and useful tool and well worth the prices I’ve seen quoted for it.
