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workshop by Handyman
Details to save down-time (17)
Couplings for air tools must have the same i.d. as the hose otherwise they will suffer from reduced pressure
WITH AIR installations, watch that you do not have unnecessarily long air hoses between supply manifold and tools, as undue length will cause a pressure drop. So if it is necessary to go some further distance from the supply to the work point, then the extra length should be in the next larger bore size.
It is important that couplings should have the same inner diameter as the hose because any reduction in the supply line size will give a reduced pressure at the tool and you may therefore fail to move a stiff nut, or reach the torque needed for tightening.
Now, assuming that the supply side is in order, I will look at tools and accessories. A good make of air tool has a range of fittings including a strong universal joint, to work either at close quarters or with a suitable slim extension to keep the bulk of the tool out of the way. For instance, to operate a socket on a set of manifold nuts can mean that a plain extension of some 10 or 12in. long may be called for, with the universal joint at the socket end.
This is a popular set-up in the -lin. size, as a wide range of jobs can be done on an oil engine, exhaust flange joints, engine side plate nuts, fuel pump and bell housing nuts, etc, where long reach is needed. In fact, there is no particular limit to the extension length.
In the same way a screwdriver bit can be fitted either close up to the machine or on a suitably stiff extension. One extension I saw recently was equipped with an attachment to take the Phillips bits for the heavier range of screws in cab door hinges and floor plates.
In addition to the rotary action tool, there is the range of equipment that can be driven by the small air chisel or hammer. This tool is of considerable value when dealing with tapered ball and socket joints on the steering assembly, and a tapered fork chisel can be used to drive into the joint which will usually part after a second or two of operation. This saves all that damage to the socket body so often seen when two hammers are used to break the joint free.
Another tool almost on the same lines, the saddle-shaped hammer head attachment, can be used instead of the wedge fork to move tapered joints, and the effect of 3000 blows per minute is that a tight trackrod end thread can be released in seconds.
In the same way the cutting chisel can be put to many uses, removing the worn liners from brake shoes or clutch disc, cutting off bolts and rivets from difficult areas in the chassis. With a suitable mandril it can be used for riveting, punching out valve guides, bushes, etc, and there is a special tool for splitting bushes.
Pistol air drill
I have not so far mentioned the pistol air drill, which is light and reliable and takes up less room on the job than the electric drill. Possibly the only complaint the operator of air tools can make is that certain types tend to exhaust over the user's hand, and on some it has been found necessary to glue on a small deflector to avoid the problem of cold fingers.
Among the impact wrenches there is now a most versatile one with a fin, drive; this tool when fitted with the kit of accessories, extension, universal joint, etc, can get at vehicle parts that present real difficulties for ring keys or open spanners, or for that matter normal hand-used sockets.
Water pump removal time, for instance, can be halved by this tool, and the same applies to generators and their concealed bolts, spigot-mounted pumps, compressors, starters, etc — all are easy meat for the fin. drive model.
For the perfectionist in air tools, there is now a flat attachment that locks on the drive shank and can transmit drive to a socket at right angles to the air tool, but operating the socket on a line parallel to the air-tool shaft. This enables the operator to send the socket in behind a radiator in the narrow space between it and the water pump or fan-blade nuts, the slim right-angle drive taking up less room than the hand or fingers. This is both a time and skin saver for the enthusiastic mechanic.
An important feature regarding air tools is the safety factor; no frayed or faulty cables, switches, fuses, plugs or ragged slave boxes, no risk of electric shocks in wet areas; and as they are lighter to use they are less tiring.