For most DIYs, a ratchet and socket set was probably one of the first tools ever acquired. When I started doing a little historical research on ratchets, I was surprised to learn that the ratcheting socket wrench and interchangeable sockets were invented in 1863. It was weird thinking that what many consider a core tool in their rollaway being a design more than 150 years old.
A ratchet is a mechanical device which allows motion in only one direction. Key components of a ratchet are: a round gear or a straight rack with teeth and a pivoting finger, called a “pawl”, backed by a spring. The teeth are evenly-spaced and asymmetrically-shaped with a moderate slope on one side and a much steeper slope on the other. The tip of the pawl engages each tooth and, when the gear or rack is moving forward, easily slides up and over the moderately-sloped sides of the teeth. After the pawl passes over the tip of each tooth, the spring forces it into the depression between teeth. Often this makes a “click” noise. If the teeth movement reverses, the pawl locks against the steeply-sloped side of the first tooth it encounters preventing further motion.
A ratcheting socket wrench has a round gear, one side of which extends outward in a square drive “nub” onto which socket with the appropriate square drive hole fits. Common square drive sizes are ¼-, ⅜-, ½-, 3/4- and 1-in. The wrench also has a detented lever which controls which way the ratchet allows movement, ie: to tighten or loosen a bolt.
“Swing Arc”, “ratchet swing” or just “swing” is the length of arc, in degrees, you have to move the ratchet for the pawl to move across one tooth. Generally, the smaller the swing, the easier the tool is to use in a restricted space. Most of the tool makers advertise their ratchets’ tooth counts and swing arcs.
In 2012, GearWrench introduced its “120XP” line of ¼-, ⅜- and ½-drive inch drive ratchets, each of which has a high, 120-tooth count and a small, 3-degree swing arc. Not only do these GearWrench ratchets offer the advantage a high tooth count offers when working in a restricted space but their ratchet mechanism has the strength of a 60-tooth count which allows the user to really pull hard on the tool. A 120 tooth count, 3° swing and strength meeting ASME requirements comes through a 60-tooth gear and a clever “double-stacked pawl” system. The patented design has the 60-tooth gear alternately engaged by two pawls giving the ratchet 120 positions and the 3° swing arc.
Turns out, the 120XPs do not have the highest tooth count. Sold by various Internet vendors, J.S. Products’ “Steelman Pro Cobra” brand ratchets have a 160-tooth count, however, that high number comes with a ratchet having a large head and handle which partially negates the advantage of high-tooth count with cumbersome size. Two other drawbacks of Steelman’s Cobra product are an unacceptably high level of “back-drag”–which means you often have to hold the socket as you ratchet the wrench back after pulling on it–and a reversing mechanism which is one of the more un-ergonomic designs we’ve run across in a while.
GearWrench puts the 120XP mechanism in its “tear drop” low-profile ratchet head and uses a flush-mounted directional lever. The double-stack pawl system has less back-drag than competing products. Additionally, the flush-mounted directional lever is easy to manipulate. Those features make for a compact, easy-to-operate tool–another advantage when working space is limited.
The 120XP ratchets are available with either fixed or six-position flex heads and we usually prefer the flex-head models especially in the case of GearWrench because their flex-head detent springs have higher tension compared to some other flex-head ratchets I’ve tried made by Mac Tools and Craftsman. Their weaker detent systems allow the heads to flop around when we don’t want them to move.
The 120XP ratchets come with either polished steel or “cushion-grip” rubber handles. We already knew about the Cushion-Grip feature because we’ve been using a GearWrench offset, flex-head spark plug ratchet with a Cushion-Grip handle for many years. We like that type of handles because they’re easier on our old, tired hands.
At the CAC’s project vehicle shop, we wanted to upgrade some of our ratchets so we ordered a set of GearWrench 120XP, Cushion-Grip, flex-head ¼- and ⅜-drive ratchets (PN 81204P. In our first use of them, we were smitten by the precise, fine-tooth feel of the 120XP double-stack pawl system, their low-back-drag and the advantages the 3° swing and compact ratchet head gave us when trying to turn fasteners in restricted spaces.
We wanted to try out the 120XP system’s strength, so we also ordered a ½-in. drive 120XP ratchet with the extra long, 2-foot handle (PN 81364). This tool is only available with a fixed head and a polished steel handle. We looked around for a really tight fastener which was, also, easy to access on which to “test” this long-handle 120XP ratchet. On an ATS-V, the rear drive axle shaft nuts are easy to get to and are tightened to 185-ft/lb. In the past we’d have to use our ½-in. drive breaker bar to undo a nut like that, as it had the longest handle (24-in) of any tool we had. We tried the GearWrench ½-in drive 120XP Ratchet and broke that nut loose with ease. Up to now, we’ve never had a ½-in. drive ratchet which was long enough and strong enough to also work as a breaker bar.
Bottom line on GearWrench’s 120XP ratchets?
They’re pretty good stuff.
For more information see the GearWrench web site.