At one time or another we have all improvised. We force some inanimate object to perform a function for which it was not designed, then later, explain to the spouse why we had to use the sterling silver spoon to pry open the can of paint. (Smart ones claim supernatural powers allowed them to bend the spoon.) In the beginning a club or stone tool served to put food on the table, or if you believe popular myth
a Conk on the head, ugh!, and you now have a new wife. We have evolved since then, and as with most specialized industries, aviation has its fair share of high tech, gee-whiz tools for every conceivable application.
Next time youre in the hanger, take a look at your trusted A&Ps toolbox. Most would make Tim Allen weep with envy, 10-15 THOUSAND DOLLARS worth of tools is not uncommon! New mechanics often asked me what are the best tools to buy, do they need this or that, and is there a minimum number of tools? There is no right or wrong answer, and it depends on the aircraft. If you go to work for an airline they may only allow you to bring a limited number of wrenches and screwdrivers, the airline will provide all of the specialized tooling you will need. You may be surprised to find that for a large aircraft, say a Boeing 737, you will only need a handful of basic tools anyway. The vast majority of work you can do on the flightline is with wrenches less than 1 inch. Tire changes, hydraulic actuators and the like usually take BIG wrenches, and the airline or Repair Station provides them.
Unlike an airliner, oddly enough, plan to invest a small fortune just to do the day-to-day inspection and repair work on a single engine Beech, Cessna, or other light aircraft. Few non-FAA approved repair facilities provide tools for the mechanics they employ. Most A&Ps prefer to work with their own tools anyway, and take pride in the fact that they keep the torque wrenches, multi-meters, cable tensionmeters, micrometers, and a host of other equipment calibrated. Its not cheap or convenient to do so, but they do. Guess what? If you as the aircraft owner complete maintenance under the provisions of Part 43 Appendix A (Preventive Maintenance), you too are required to use calibrated tools, current maintenance instructions, and approved parts, just like the professional A&P.
Lets start with a place to store these soon to be acquired implements. For the average weekend of bloody knuckles, Sears or (gulp) discount tool supplier will have a wide selection of rollaway, non-moveable, or hand carry toolboxes. Expect to pay $200-500 for an okay quality lower rollaway and upper chest. If you want the best, expect to give MAC or Snap-On tools 900-8,000 (yes, eight thousand) hard earned dollars for the high-end toolboxes. All perform the same basic function of keeping your tools convenient, secure, and organized. Beyond that, its simply a matter of how much you want to pay and where you intend to keep the toolbox.
I swallow hard when I hear discount tools, I still have scars from a $5 wrench that took $300 worth of skin off when it broke. Discount tool suppliers sell sets made in Taiwan, China, or the like. These tools WILL hurt you. If they dont break, they may not fit properly and will round off nuts, bolts, or what have you, and you will end up replacing those parts, sending more money down the drain. You can find some cheap tools that work in light maintenance applications, or to bend, twist, and cut-off for those hard to reach spots or one-time use items. But for the most part, you will get what you pay for!
While I dont want to say one tool manufacturer is better than another, I would say that dollar for dollar, Craftsman tools are a good trade off between price and quality for the average weekend wrench bender. Watching the paper, you can find good sales on wrench sets, ratchets, and socket sets. Other good places to find tools are pawnshops or swap meets. Look em over good before you plunk down your cash, and make sure it is a full set. I would recommend a combination (open and boxed end) wrench set. You will need 5/16 to 1 range for most applications. The same size range for sockets, 12 point will fit more applications, but a 6 point (number of sides on the socket) will work as well. Wrench sets will run from $79-149 on sale, depending on the number of wrenches in the set. Another $30-70 for most socket sets. Most light aircraft use SAE (Society of Automotive Engineers) sizes, and a few aircraft might have metric parts installed, but not many. A few old British aircraft will have British Standard parts installed. I say OLE chap
pass the adjustable spanner, works in this case, cause I dont know where you can even purchase these tools!
A word about torque wrenches: Dont waste your money on the beam type, those that have a wire running down the center of the handle with a scale attached. They cannot be calibrated, are not very accurate, are cumbersome to use, and, in my humble opinion, are JUNK! The torque wrench will be your biggest single expense, most quality torque wrenches start at 150 bucks and may reach $250. Spend the money! One improperly torqued spark plug will cost a lot more than the wrench when you pull the Heli-coil insert out of your cylinder. Or worse, as you make the off-airport landing because the spark plug blew out of the cylinder, causing a loss of power and resulting accident. Its your choice: $250 for a torque wrench or $20,000 to fix the aircraft after the accident (if youre still around to fix it that is). In my 25 years of maintenance experience, I have never seen a properly torqued plug come out. I have made a lot of money on improperly torqued plugs though.
Now that you have a quality torque wrench, it will need to be calibrated once every year, about 25 bucks a pop. Keep the paperwork from the calibration, I will ask to see it when I run into you on the weekend.
Basic tool use: NEVER, NEVER, and one more time, NEVER break torque with your torque wrench, you just paid big dollars for it and pay to keep it calibrated. Use your combination wrenches for this task. When possible, use the box end portion of the combination wrench to break torque and the open end for faster part removal. Lately, a new style of open-ended wrench has entered the market, these wrenches have a cutout on one side and allow you to use the wrench almost ratchet style. I have not used any of these, they may or may not be of any value for aircraft use. I would be concerned about rounding the heads of bolts or slipping and busting a knuckle, and I havent seen many in professional A&P toolboxes. That may say it all!
In the next issue Ill talk more about tool usage, the dos and donts of battery powered tools, technical data, and the how-to-do-it of weekend maintenance
till then: MAKE IT RIGHT FROM THE GROUND UP!