| Ultra-Duty Automotive Impact Wrench
This wrench is a peach. I first became aware of it while watching a technician change a 911's suspension. Asked if he had any one tool that was a favorite, he pointed to his Ingersoll-Rand 2112. After that, I kept an eye out. It turned up in other clothes under at least three reputable brand names. It is the smallest, lightest and most powerful 3/8-in.-drive pistol-grip impact wrench available, weighing only 2.65 lb and delivering a maximum of 260 ft-lb torque in reverse (lefty-loosey). There are also 1/2-in.- and 3/4-in.-drive versions.
I've been borrowing a friend's air tools for some time, in exchange for me lending him the Power Tank system ("Tool of the Month," 03-01) when he needs to run them in the woods. One of his impact wrenches was bought for the staggeringly low price of $9.99. At first, it was small, lightweight and effective, but it ran roughly and sockets didn't always fit its drive well. After just a few months, it was accidentally dropped, as tools often are, and stopped working. My friend couldn't figure out how to repair it, so he bought another. No big deal, except the original stopped when he needed it, miles from the nearest tool store--or any store at all. I decided it was time to begin my own collection of air tools and started with the Ingersoll-Rand 2112.
Ingersoll-Rand's instructions are extensive. This little jewel is a serious machine, despite its small size and external simplicity. The instructions include complete service and repair instructions, as well as an exploded, numbered parts diagram. Unlike some made-in-China special with power sanding marks on the case, you should be able to get parts and service from Ingersoll-Rand for as long as you are around to need them.
Ingersoll-Rand recommends 3/8-in.-diameter hose and fittings as a minimum to ensure that the energy of the compressed air reaches the tool, rather than being used to force the air itself through restrictive plumbing. Think of the system like an engine: The easier the air gets to where it does its work, the better it performs. Most people are familiar with 1/4-in. fittings; 3/8-in. fittings screw into the same 1/4-in. pipe threads. They cost only a little more but are worth making your shop's standard. Buy a set of impact sockets, the heavy-duty black kind. Your chrome sockets are not made to stand up to the punishment the impact wrench delivers and can fail at the worst possible time. Don't forget to lubricate the wrench regularly.
I find the Ingersoll-Rand 2112 lightweight, easy to hold at odd angles and in tight places. It takes up little space in my portable toolbox. With no load, it spins very smoothly, indicating a precision lacking in lesser wrenches. Its direction can be selected with the thumb of the hand holding it, while the throttle trigger makes it easy to go for full power or just barely snug a fastener, leaving the tightening for hand tools. The power adjuster on the back of the case works only in the forward direction, so full power is always available for removing fasteners.
The best price I have seen for the Ingersoll-Rand 2112 was on a sale at Harbor Freight Tools, but you can buy one nearly anywhere. Look for the features; even if it doesn't say Ingersoll-Rand on the side, you'll know when you're looking at a 2112.