Selecting A Homebuilt Design

There you are, wandering through acres of airplanes at Oshkosh. The adrenalin ... someone to be your spouse. .... ing should be that you just like to build things.
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SELECTING A HOMEBUILT DESIGN PART1

Matching the Machine to the Man by BUDD DAVISSON

66 Scudders Rd. Sparta, NJ 07871

We all know the feeling. There you are, wandering through acres of airplanes at Oshkosh. The adrenalin is pumping and your fingers nervously twitch while fondling your checkbook. You've made up your mind. This is your year to build an airplane. No, not just AN airplane, but THE airplane. It will be your pride and joy. The airplane will be your statement to the world. It will be your gateway to faraway places. It will be something gossamer and magic. It will be ... This is a dangerous time! This is the time when rationality and logic have been overpowered by the dread disease, Igotabuildanairplanitis. At exactly the critical moment, when your saner self should reign supreme, your mechanical hormones are running amuck. You are in deep trouble and don't even know it. You are about to let those hormones pick a homebuilt design for you and, in so doing, create one of the longest lasting, most knuckle busting nightmares of your life. This would be a good time for a really cold shower. Or two! Selecting a homebuilt to build is far more complicated than, say, picking someone to be your spouse. At least in that case hormones were supposed to be part of the equation. The only way to approach the problem of selecting a design is with cold rationalism. This ain't easy. In fact, it can be darned hard, but by following some simple guidelines, it can be made easier and, when the decision is made, there is a better possibility of not only completing the airplane, but of having the machine match the man (or woman). Undoubtedly the most common mistake is basing the "which airplane" decision entirely on the airplane and what it does. Little or no thought is given as to how that airplane fits into the realities represented by our own life. In fact, without giving it some thought, many of us don't really know what the realities of our life are. That's okay, since not

knowing the realities is what keeps most of us from leaping off tall buildings. However, jam a project as big as building an airplane into the average life and suddenly the realities become very real. That's why the man/machine match is so critical. We don't want to put an aeronautical square peg into a hexagonal hole. Most of making the man/machine match right the first time is carefully evaluating all those things which enter into the situation, as it actually exists. The decision has to be based on our real life aeronautical situation, not the life we see with our emotionally closed eyes. Rule one, naturally, is don't take your checkbook to a fly-in until you've gone through the complete evaluation cycle. The evaluation process centers on four basic areas. The first is a self evaluation in which you stand off and take a hard, objective look at yourself as a builder, pilot, family man and provider.

". . . the most common mistake is basing the 'which airplane' decision entirely on the airplane and what it does." The other areas include evaluating your personal environment in terms of

a place to build said airplane. Then, it's necessary to look hard at the mission you have in mind for the airplane. Granted, we all want a 300 mph, fully aerobatic, four seat amphibian that burns 3.4 gph (of diesel) and builds in three months and can do everything. But, that isn't the real world. We have to decide exactly what it is we're going to do with this homegrown magic carpet

so we can select the best compromise as represented by each design. Last . . . and nearly least . . . is the evaluation of the airplane possibilities themselves. By the time you've taken all the other steps, many of the contending designs will have been eliminated by the decision parameters developed. You'll also have spent enough time thinking about it that most (not all) of your hormones will be under control. When it comes to self evaluation, some of the simplest questions we must ask ourselves are the hardest and often lead into entirely different subjects and directions. However, the questions we have to ask are fairly short and concise. It's the answers that get long and drawn out. The questions are the following: - "Why do you want to build an airplane?" - "What kind of a builder are you?" - "What is your 'life situation' in terms of time, finances and family?" - "What kind of pilot are you?"

Why Do You Want To Build An Airplane? If you answer the above question by saying "Because I want something to fly", then you are barking up the wrong wind tee. If your only reason for building is to fly, then chances are you'll never finish the project because your urge to fly will overpower your urge to build. If, during the project, the builder is constantly looking down the road, visualiz-

ing himself wafting out over far horizons, he will become discouraged and quit. In a project where progress is measured in millimeters, the horizons never seem to get any closer. There are thousands of flying machines out there that can get a pilot up and down without those thousands of hours of nitpicking labor which preSPORT AVIATION 37

cede the launching of a homebuilt. They are airplanes a pilot buys to fly. A homebuilt is an airplane in which the act of building is an end in itself. It is an unbelievably long, arduous task that will never be completed if it is looked at as a task or a stepping stone to someplace else. Acceptable reasons for building an airplane are almost always a little hard to get a handle on and they vary from builder to builder. The combinations of reasons vary as much as the personalities of the builders, but they almost always include some form of the act of creating and the tremendous satisfaction which comes from creating something that lives and breathes, as an airplane does. Also, acting as glue which holds together all the other reasons is a stubborn streak of individualism, of wanting a machine that is strictly, unequivocally the way the builder wants it to be. The most important reason for building should be that you just like to build things. Simple as that. What is being built is secondary. The fact that many homebuilts offer performance not normally available elsewhere isn't reason enough to jump into a homebuilt project. With a number of noteable exceptions, performance that approximates a homebuilt design is available in ready-to-fly spam can form. For instance, if you just want to do aerobatics rather than putting 3,000 hours into building a Pitts, buy a used Pitts S-2A - the dollars work out the same. Rather than building a Glasair II or Long-EZ for the long range cross country performance, put ferry tanks in the back of a late model Mooney or Bonanza. This kind of approach is for those who give "I want to fly" as their reason for building an airplane. This kind of approach isn't even worth discussing for those who have the mechanical creative bug running through their veins and have to have something that's as individual as their thumbprint.

What Kind Of A Builder Are You? Evaluating yourself as a builder has absolutely nothing to do with what you have done or what you can do. Skill and experience aren't part of the equation, although they do help. They aren't important because there is not one skill involved in building any airplane that can't be learned by the average guy at the airport who has the right attitude. And that is the magic ingredient . . .

attitude. The right attitude involves a willingness to do things "right" and learn what has to be learned. If this isn't your attitude, if your frustration level is low and 38 JANUARY 1989

interest in learning is nil, don't build. Don't even think about building. Even those who build things around the house might not know what their actual builder attitude is because they've never thought about it or have never tackled a long term, detailed project. If that's you, try the following as a test case: Build a good sized, flying model airplane and judge your feelings and attitudes this brings out. To make the test case a little more concrete and a heck of a lot of fun, buy a Sig Manufacturing, Montezuma, IA, Chipmunk kit (CL-19) and a Fox .35 or .40 engine. This is a U-Control (wires running to a handle, with you attached, in the middle of a circle) stunt ship with 53" wing span. By the time you are done building, finishing, flying (and repairing) one of these, you'll have gone through a tiny microcasm of bulding a real airplane, including scrounging up all the requisite parts. You'll be in and out of the project for about $100 and it will tell you a lot about yourself. If it shows you to have the wrong attitude, the C-note saved you thousands. If it turns you on, it showed you a new side of yourself and, at the very least, got you into a sport (U-C stunt) that's a lot of fun in its own right. One of the most important factors of the "builders attitude" involves "project orientation." This means the project at hand is the only project of immediate concern. In other words, the tiny piece you are grinding/sawing/bashing into the appropriate shape is the project. Granted, there are thousands of such projects under the umbrella of the larger one, but by concentrating on them one at a time, the job seems much shorter. Also, there's a lot to be said for sitting down to build a widget and seeing it started and finished in one sitting. The satisfaction factor is much higher than judging success and progress only by looking at the whole. By building the airplane one little project at a time, when you run out of little projects you'll look up and realize the airplane is finished. Another factor in project orientation is planning. There is a certain logic to the way any project proceeds and that has to be mapped out in advance. That doesn't mean setting strict time schedules (which are a sure way to disappoint yourself). That means certain parts and assemblies have to be done before others. Some parts can be built totally independent of all the rest and that can be used to your psychological advantage. Plan two different lines of building - one will involve longer term components and the other will involve those millions of little parts that can be built in less than an hour. This approach is more important than it appears. All of us run in cycles: one day we'll be ready to sink our teeth into something really meaty

and long term. Other days we want instant gratification, something that we can do right now. Also, some days we need work that is gross in nature (building work benches, sawing tubing, beating the dog) and others demand fine detail work (wiring, instrument plumbing, fitting clean-up, grooming the dog). If we recognize those cycles and work with them, then even on those days when we would usually not feel like working on the airplane, we can find something that fits our mood. Discipline is probably one of the most important, and hard to control, parts of project orientation. The guys who finish airplanes don't necessarily lock themselves in their shops for days on end, having their wife slip pizzas under the door. Most of them do, however, designate at least one small project a day to be finished. Many of them say all they ask of themselves is that they physically touch the project at least 4-5 times a week. That way they don't drift away from it or let other things get in their way. They also know, once they've overcome the sand-in-the-butt inertia that overtakes us all right after supper by simply walking into the shop, they'll wake up and work for whatever time is available to them. Another form of discipline is actually using available time. There are lots of little tasks that can be done in just a few minutes . . . removing masking tape after painting, sweeping the shop, etc.

"Discipline is probably one of the most important, and hard to control, parts of project orientation." These can be done while waiting for dinner or during a lull in family activities.

For instance, I once timed myself and

found it took 17 minutes to fit a diagonal piece of tubing and tack it, and 12 minutes for a vertical. So, when I found a spare 20 minutes I was out in the shop making headway. Paying attention to detail is another of those attitudinal factors that isn't innate with everybody, but, with some personal head banging can be learned. Getting the details right is critical and it is absolutely essential the feeling of "good enough" isn't tolerated. Down to the last detail, the builder must remember exactly what he is building and why every detail counts. An airplane is a machine that gets you just high enough to bust your tail and "good enough" doesn't cut it. Even/time you make a fitting and an edge has a tiny

nick that needs to be cleaned out, one you know probably doesn't make any difference, you have to think about being at 3,000 feet and wondering whether that nick really was inconsequential. There are no inconsequential parts of an airplane and strict attention to detail has to be part of the project, from beginning to end. The builder attitude can be learned in its entirety, but sometimes it has to be worked at. An excellent way to practice it is in building your workshop. In later parts of this series, we get up to our necks in the question of workshops and, when we do, certain parts of it are made for attitude development. It's also a great way to decide which are thumbs and which aren't. The materials used in constructing aircraft are also something an individual has to keep in mind when doing his builder evaluation. Folks are just naturally more comfortable with some materials than others, historically. However, that hasn't made much difference in what airplane is built. All people bring a rudimentary knowledge of wood construction into aviation, but few build airplanes out of it. Since all the other materials require skills that aren't commonplace, that in itself is a testimonial to the ease which new skills can be acquired.

What Does Your Life Actually Look Like? Tossing an airplane building project into many households would be like throwing a skunk in a bathroom window unless some preparation is made and the right selection is made. The selection affects the family almost as much as it does the builder and its effects are in two areas - the first is while it is being built and the second is when it is finished and flying. Let's look at the flying side of your life first. Let's say right now you had an airplane out at the airport, ready to go. How many times a week can you get out there and how much time can you dedicate each time you do? If you have a warp nine, cross continental runner, how often will you have several days to make use of its long legs? Regardless of what we want in our airplanes, often our life style dictates we opt for something else. If your weekends are filled up with soccer games, birthday parties and trips to the dentist, chances are the best you can do is a Sunday morning at the 'drome. In that situation, as much as you want a Glasair III, a CUBy or Pitts actually makes more sense. Also, is your family part of your aviation world? Do you actually need the second, third or fourth seat? If they

travel with you, how big will the kids be two or three years from now. A couple of years growth will really screw up CG calculations and foot room disappears faster than last week's sneakers. And then there is the ugly question of money - how much will be left over after building to feed the new bird? Close to a couple bucks per gallon and it adds up, if long weekends in the Bahamas are part of your plans. It doesn't even enter the picture if you're putting an hour a week on your Pitts or Pietenpol. The same factors have to be weighed when building the airplane as well as when flying. The average airplane consumes between 1,500-3,000 hours of free time that isn't really free. It is stolen from someplace else in your life and it may have to come from your sleep time, if it's not available anywhere else. That amount of time at two hours a day and seven days a week is 750 to 1,500 building days. In a best case scenario, that's a full two to four years. Can you actually get 14 hours a week free? How much time can you steal from your family without it causing problems or building resentment towards the airplane project? What about your job? Does it take you away from home so

"Regardless of what we want in our airplanes, often our lifestyle dictates we opt for something else." family-time is even more precious? What about your own interest level? Can you keep it up for 14 hours a week for three years? In many cases, the only way it will work is by the nickel and dime time slots mentioned earlier and doing the 10 to midnight shift. It is critical the builder recognize the family's rights and the demands of the rest of his life. If he shorts the family in the time department, he stands a good chance of building a wall of resentment that will be yet another obstacle he has to overcome to build the airplane. Here comes the question of money again - it used to be, when the only investment to get started on an airplane was 30 bucks for a roll of plans, finances could always be worked out. The pieces were bought a bit at a time and the bite was small going in. Today, since the majority of folks are building kits, there is a pretty good hit right up front. The average bank won't give you the time of day when it comes to a homebuilt, even though the same bank will loan money to rebuild an antique or

classic. So, the builder has to figure out what he can afford and when.

You As A Pilot Pilot skill is the same as building skill. It isn't important because it can be learned. Absolutely anybody reading this can be brought up to speed in any airplane in the world, given enough time. People who fly Pitts or Mustangs aren't supermen gifted with talents which are unobtainable. They have just spent the time and money to learn. It comes back down to attitude, especially the attitude towards challenges versus enjoyment. It is important you poke around in the mustier corners of your mind to see if you would rather get up and down with a minimum of hassle or whether each flight is an experiment to accept the challenge to improve. This is probably the most important aspect of making the man/machine match work. If you are a pilot who dearly loves the challenge of taming the airplane and making it do what you want, you may find yourself bored with a Pietenpol in a matter of seconds. To that kind of a driver, the challenge of making a nohop landing in a Pitts is justification alone for building one. If, on the other hand, your kind of flying is gently floating up off the ground to groove on a lemon-colored sunset and arrival and departure are simply to be tolerated, don't build a Pitts or other high demand airplane. Your mouth will be so dried out all the time you won't be able to spit or whistle for weeks after each flight. Both approaches to flying are correct and one is no better than the other. But it is important the builder know his feelings about flight before he starts sawing foam/tubing/wood/aluminum. This seemingly simple combination, matching the airplane to the pilot's attitude, not skill, is one of the reasons there are so many homebuilts for sale at 30-40 hours. They aren't bad airplanes, they just don't match the pilot's attitude envelope.

Summary We are one-third of the way through the evaluation process and it can be seen how the initial person oriented phases have a slight Psychology Today look to them. Next month, we'll get into the physical set-ups required to build an airplane. In fact, we'll design a workshop and present some working drawings for work benches and other crude, but needed, items. Until then, climb under the electric blanket, turn it up to nine and think about airplanes. And let your wife hold the checkbook. SPORT AVIATION 39

SELECTING A HOMEBUILT DESIGN The Building Situation by BUDD D&VISSON

66 ScuddeVs Rd. Sparta, NJ 07871

f\r\ airplane project actually consists of two construction phases . . . or at

least it should. The first phase is building the nest - the workshop - in which the new bird will be hatched. The second is building the airplane itself. The actual construction of the airplane is colored so much by the work environment in which it exists that it makes sense to approach the workshop as a separate project . . . one that is both a training ground for developing building skills and an absolutely essential part of the airplane's support system. The importance of the right workshop and the right environment cannot be underestimated. Two to four years of your life are going to be spent in this environment and its effect on you can actually make or break the project. If it is a dingy, left over space between bicycles and garden rakes, where you are constantly fighting the elements, the family and the spiders, it is an uphill battle to keep your spirits up. If it is a nicely organized, bright, well lit area that is dedicated to you and your airplane, then the only obstacles are inside your head. For the above reasons, it will actually speed up the building process if you forget about what airplane you are going to build and concentrate on giving yourself the best building environment you can, within the limitations of your physical set-up and finances. Building an airplane isn't an inexpensive proposition and putting a few bucks into the work environment will not only save you money by helping guarantee the completion of the project, but the shop will always be there for other projects.

How Much Space Is Enough? It has often been said there is no such thing as too much space when building

airplanes, but, for our purposes, that's not entirely true. Yes, there is an absolute lower limit, but there is a practical upper one, too. The space has to be lit and heated, which can be expensive, and you are constantly transiting from one tool to another and, if those distances are relatively large, it can get tiresome. If a huge amount of space is available, the best way to use it is to designate a "live" work station area that is of convenient size for the largest component, generally the fuselage, to be

The Proximity Effect More important than space is the workshop location. A gorgeous workspace a block away might as well be across the state, in terms of the obstacles it presents. Everything humanly possible must be done to bolster the psychological aspect of building an airplane and proximity to the project is one of the primary factors. A workshop that is separated from the house by as little as 20 feet will see less activity than

"A single garage, 16 ft. by 22 ft., is a rock bottom minimum for building airplanes . . . " worked on. All the tools and benches would congregate in that area making for an efficient traffic pattern. The rest of the space can be used for storage and the old saying absolutely applies to storage . . . there is never too much. Coincidentally, for the size of airplanes we are usually building, a work station generally winds up being about the size of a double garage, 24 feet by 24 feet. Granted, another ten feet in each direction would be nice, but don't let that stop you. Double garages have spawned thousands of airplanes and will continue to do so long after we're not around. A single garage, 16 ft. by 22 ft., is a rock bottom minimum for building airplanes and even then extra storage space for completed components would be nice. Yes, lots of airplanes have been built in back bedrooms and living rooms and I know of a T-6 being restored in a third story loft in downtown Manhattan, but that's the hard way to do things. If you are constantly wedging between the wall and a wingtip to get to tools, building is going to become a chore.

one that is in the basement. And the basement one will see less activity than a workshop on the same floor as the kitchen and living room. It has to be easy to get up from the dinner table and amble into the workshop without worrying about putting on a coat or climbing into the car or slogging through snow/rain/wind. In many cases we're only talking a difference of seconds in travel time, but it is the mental effort required to overcome the after-dinner-blahs that counts. The fantasy workshop situation would be one which is worked into the house while the house is still under construction. The shop would be about 30' x 40' (tack on a few feet here and there for personal taste) and during construction it would be treated just as if it was another room in the house. The finishing crew would sheet rock, paint and trim it like it was a giant living room. The floor would be a good grade of plywood finished in urethane or epoxy, with the top layer of ply designed to be taken up and replaced whenever it got too beat up. Wood floors in workshops are great because they are easier on the feet, warmer and can be nailed into for jigSPORT AVIATION 31

ging purposes. With this kind of workshop, a builder could go padding right into the shop in his bathrobe and slippers and feel perfectly comfortable. It would have a "real room" feel, rather than the cluttered, dungeon look most workshops eventually develop. On the subject of wood floors - one of the nicest building situations seen recently was a T-hangar in which the builder constructed a floor of plywood over a 2 x 4 joist framework laid on the floor. Not only was it a "soft" feeling floor that eliminated the cold concrete, but his heating was piped through the framing which warmed the entire floor. He cut floor vents wherever he needed more heat. Great idea and not expensive! Although a minor point, it is worth it to sheetrock the ceiling of basement shops for several reasons. First, it brightens the space considerably because it reflects light and does away with a dingy overhead. Second, it forms a vapor barrier which not only can be sealed to keep out fumes, but is a fire barrier was well. Never done any sheetrocking? Nothing to it, but get a friend to help because the stuff is heavy and awkward.

Let There Be ... Ranking right up there with proximity is light. Workshops need light. Lots of it. In fact, if enough light is used, it often makes up for other shortcomings, such as scroungy walls or less than enough space. And light is relatively cheap, at least in metropolitan areas. This is true because the penny-saver resale magazines given away in grocery stores almost always have used florescent fixtures listed for sale. Remodeling companies and industrial contractors are also excellent sources, since, when they rehab a building, they seldom reuse the lighting fixtures. The ideal fixtures are the two tube, eight footers, but that's not imperative. Just get what's available, but make sure they are 110 V, since some industrial units are 220. Most of the time they run in the $12-15 range complete with tubes. A neat trick is to take a four foot florescent fixture (two or four tube preferably) and make a stand for it to be used as a portable light. It can be stood up or laid down and provides excellent, glare free light where it's needed. A knock-down design is shown, so the unit can be transported or stored flat when not in use. You'll need portable lighting in addition to the above and that should be in two varieties - a florescent drop light (not an incandescent because they get too hot) and a couple of clamp-on light reflectors like those sold in photo stores. These are simple aluminum reflectors that take a 100 watt bulb, not the expensive photo floods. 32 FEBRUARY 1989

The Elusive Search For Heat

Those of you who live in southern climes and who work in your shirt sleeves year round can skip this section. And those of us who worry about snow drifting under the door don't want to hear your complaints about how it sometimes gets down to 60 degrees in your shop. One of the dreariest work situations imaginable is a cold workshop with concrete floors. No matter what kind of snow suit is worn, the temperature works up through the soles of your feet and eventually you are cold soaked. Building airplanes in that situation is no fun. On the other hand, working in a toasty warm workshop when the wind is howling outside appeals to the toymaker in all of us - it's what I call the Geppetto Syndrome. A warm shop on a cold day triggers something psychological that makes us WANT to work, to create little pieces that will eventually fly. Without that warmth, the cold becomes a major mental obstacle to building. And, of course, cold stops

just a sheet metal plenum, which is generally attached to the heater when you get it. Even the smallest ones throw out more heat than is needed, so don't put a 150,000 BTU unit in or you'll be able to fry eggs on the windows. Insulation, of course, is another bummer in the north. Insulating the walls presents no mysteries, but the traditional garage door is often approached wrong. Besides the fact that the average overhead door leaks like a sieve, they practically have a negative R value. They may keep out the wind, but the cold comes right through. The average unheated garage, with the usual overhead door, will go down to within a few degrees of the ouside air, but a proper set of insulated doors will keep it above freezing almost regardless. A "proper" set of doors is open for a lot of discussion, but the simplest ones are nothing but two giant, handmade, hollow-core slabs that are insulated and hinged to the door framing in front of the original overhead door. Use two of these slabs to each door opening to keep hinge loads down. Construct the doors using 2x4s for framing, preferably hemlock fir or pine,

"If you are stuck in an area where it snows and gets miserable 6 months of the year - like most homebuilders are - don't try to cut corners on the heat." certain processes, pardon the wordplay, dead cold. If you are stuck in an area where it snows and gets miserable 6 months of the year - like most homebuilders are don't try to cut corners on the heat. Forget about portable electric heaters or camping stoves. Cut right to the bottom line and go for something that really works. There are a number of really ingenious new heater designs which include gas and oil wall heaters capable of perking up a garage and require only a vent cut in a wall and a feeder line. Most oil supply companies know what's available. A less expensive way to insure plenty of heat is to lay your hands on a used hot air furnace, preferably oil fired. Any heating contractor can point out units he has removed that are often to be had for the taking. Others are listed in the penny-saver ads. Make sure it wasn't removed because it was defective, however, because some of them are hard to repair. An oil fired, hot air furnace only needs to be set up on blocks in the corner of the shop, a vent run through a wall, an oil line run to it and plugged in. It can be wired with a thermostat, but many builders just plug or unplug it to control the heat. No fancy duct work is needed,

since they are lighter. Skin the frame on both sides with 1/4 luan plywood. Plan the framing 16" or 24" on center, to use normal fiberglass insulation. If you're sensitive to appearance, the outsides of the doors can be treated in a number of ways, including diagonal cedar siding, etc. Much lighter doors can be made using 2" Styrofoam insulation, 2x2 framing and the same 1/4" skin.

Equipment As with light, there is no such thing as too many tools, but it is easy to get carried away and buy expensive items not really needed. An airplane is not a complicated machine, so you don't need a machine shop. In fact, many airplanes have been built with nothing more than a hacksaw and power drill. The key is to buy the stuff you'll use and hire out the work needing a lathe, and the like. So, what should be on your Christmas list for this year? Assuming you already have most of the standard hand tools, number one should be a good drill press. Check any you buy for movement in the quill shaft (the part that moves up and down with the chuck), as a few of the imports are too loose. Also, don't get a bench mounted unit unless

planning on putting it on its own stand. One of the key ingredients of a homebuilt aircraft shop is flexibility and bench mounted tools work against that. The tools should be such that they can be moved around to rearrange the shop to fit a particular job so the tools should be freestanding wherever possible. Another necessity, although it doesn't sound like it until you've worked with one for awhile, is the stationary belt sander. The most common size uses a 6" x 48" belt and usually has a disc on the side, which isn't really needed. This little beauty cleans and trues up fittings and edges so fast you'll wonder how you ever got along without one. Combine this with a power hacksaw and a few files and your shop won't need a milling machine (very few actually do need one, anyway). If any steel is used at all, one of the import power hacksaws is worth its weight in gold. Although primarily designed as horizontal cut-off saws, they all come with table attachments to use them as regular vertical bandsaws and they work great. Granted, they don't work as well as a Do-AII bandsaw, but for a couple hundred bucks they save hours of groaning and sawing. With a 14 tooth blade, they even work as wood saws, although that isn't their forte. Make one fitting on one of these things and you'll run right out and buy one. Another goody everyone should own, although it shouldn't be used even once on the airplane, is a high quality power screwdriver like a Milwaukee "Screwgun". Although a rechargeable, variable speed 3/8 drill will do a similar job, when combined with hardened screws, a Screwgun is the handiest shop and jig assembly tool in the world. If not familiar with the tulip headed, hardened screws, they are basically an outgrowth of sheet rock screws. They are hardened and double threaded, so no guide hole is needed and they pull themselves flush with the surface and they are available at every lumberyard. Using a screwgun and these screws, everything from sawhorses to shelving and benches will go together lightning fast. After discovering this combination, most folks forget where they left their hammer and nails. After getting all your tooling together, go buy a dozen four-way outlet boxes and matching outlets, wiring nuts, and 12-3 romax cable and set about running electrical outlets all over the place. Save two of the four way boxes to make a couple of 25 foot extension cords with four outlets on the end. For several reasons, an exhaust fan should also be part of your equipment list. If the shop is part of the house, the fan will be needed to carry fumes away from the rest of the family and, in so doing, insure domestic tranquility. Some of us like the smell of butyrate or polyester, few spouses do.

The fan will also be needed if any amount of serious painting is going to be done. If that is the case, an explosive proof fan should be considered. These things are so expensive you'd think they were part of the space shuttle, but they are well worth it for the peace of mind. A large one isn't needed. If it is direct drive, a 20" fan will practically suck the doors off the average size garage so even a 14" would suffice.

Storage Versus Floor Space "Stuff" accumulates. It is a law of nature that we, as a species, engage in activities that generate stuff. All of which needs to be stored. In a workshop, the trick is to store the stuff in such a way it doesn't eat up precious floor space, but to do that takes a certain amount of planning. Stuff comes in a couple of categories: Sfuffthat is needed often; Stuff needed seldom and Stuff we never use but can't bear to throw away. The last category goes out of the shop and up into the attic the instant a decision is made to build an airplane. A workshop should have no place for dead storage. It is a working, living space and all of its space has to work for it.

work bench. The ideal work bench is one which is perfectly flat, level and square, weighs nothing so it can be moved when necessary, yet it is absolutely stable and is expandable to handle different sized jobs. Oh yes, and the surface is unfazed by welding torches, epoxy and dopes/paints. This is the mythical work bench that gave birth to the equally mythical 300 mph, aerobatic amphibian we mentioned in the last installment. Everybody has an idea of a work bench in their minds already. It is usually a bunch of two by fours, nailed to four by four legs with a heavy plywood top. And that probably covers 90% of the work benches in existence. But in building airplanes we need more flexibility than is demanded of most work benches and less brute strength. For one thing, we need different sized work benches for different parts of the project. For instance, we need a bench that is about 16 feet long but only a couple feet wide to do a Pitts fuselage. Then we need a bench five or six feet wide, but only eight feet long to do the Pitts wings and tail surfaces. Every project needs a different sized series of benches to handle different parts of the project. Also, when done with a space consuming giant assembly

" . . tools should be such that they can be moved around to rearrange the shop to fit a particular job . . . tools should be freestanding wherever possible." Since floor space is critical, that means the equipment and benches which have to occupy floor space should be mounted so their bases provide storage. This is especially true of benches. Any other storage should be hung on the walls in the form of shelves and cabinets. Again, the penny-saver ads have used kitchen cabinets that are invaluable for shop storage. Watch the ads for the small kitchen base cabinets that are about a foot or so wide. They make excellent work station mountings for benchgrinders, vices, etc. and are very portable so they can be moved around the airplane.

Work Benches: Major Project Number One Your work benches are at least as important as any piece of equipment in the shop. They form the datum, the benchmark around which everything is built. Whether steel tube, composite, aluminum or wood, whatever the material, they are constructed on work benches or in jigs which are a form of

bench, we want to either get rid of it or convert it into a more useful size. Keeping in mind that airplane parts weigh next to nothing, we designed a bench that has served us well for years. The original concept sprung from our habit of making temporary benches out of factory second, birch faced doors. Because these were so thin, they had to be faced with 1/4" ply for durability, but this gave an endless variety of bench widths and they were all light. The next step was to custom build a "door" type bench top. Doors work so well for benchtops because they are not only light, but extremely stiff and retain their shape because they are essentially plywood skinned, monocoque panels. But they aren't quite rugged enough. Our "doors" are constructed of 1 x 3 fir and 1/4" luan plywood. To build in flexibility, the benches are made in sections that can be bolted together, the size of which would be determined by the project. A tubing airplane, for instance, would use benches built in 2x8 modules which would be bolted together to make 4x8 or 2x16 benches. Other birds would SPORT AVIATION 33

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need larger or different sized panels, but the concept remains the same. In addition to the above benches, each shop needs at least one normal work bench for general use. Industry standard width for that type of application would be 30 inches. Glance at the accompanying illustration and it can be seen that the benches are a cross between a wooden airplane and a wood butchers festival because they do use a lot of airplane style construction. The 1/4 skins are all glued and tacked and framing is glued and screwed using 3" number 8 hardened screws. Liberal use of gusserting and carpenter's glue produces an incredibly stiff work bench that can still be picked up and moved by one man. In fact, rollers can be built into one set of legs to allow the bench to be moved like a wheelbarrow. These work benches go together much faster than they look and they present some interesting challenges to the would be airplane builder. For instance, the top frames must be con34 FEBRUARY 1989

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