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Constructing the Fuselage

The Fuselage comes in two big boxes, one the same size as the wing assembly box, the other about 3 feet by 5 feet. When opened and parts distributed evenly about the room they form quite a collection of wood and metal pieces. The windshield comes in a big sonoco tube all by itself, and until I pulled back a section of the protective covering, I was confused about what the heck it was. After careful consideration, I will in fact build the fuselage in the same place as my other pieces, in the unfurnished upstairs room of the house.
You may of course be thinking, how the hell am I going to get the plane down in one piece? Of course a fourteen foot fuselage is too large to go down the steps. The windows of the room are completely removable. I had planned on using a simple pulley system and the extra aluminum square tubing from another project, to construct a small arm which would extend out from the house by six feet or so. However, I thought up another way.  If I simply string a heavy, taught steel cable from the inside of the room to a tree, I can use a pulley and rope to slowly lower the structures at an angle to the ground.
At this point, anyone following the construction is probably thinking, Why would I want to build one of these, when it takes several years to do it? I probably could have spent all my spare time in the plane room building the plane, but as I got married during the course of the project, I think my wife may have objected to that. If you are single or have been married a while...... go to it.
I have completed the workbench, and after a little work the turtle decks were completed. I also built the engine mount base and the bulkhead for the section behind the seat.

I set them aside, to work on the main fuselage. The lines were quickly laid out on the table, and so far the hardest part has been cutting all the members on long angles. For example, on piece of wood is less than one inch wide, but across this small measure, a six inch long cut slices the end off at about fifteen degrees. A coping saw and some clamps make it easy. What I would give for some complex, expensive power tools every so often.
I have glued up one side of the fuselage. Next I will have to pull staples, and built the other side directly over the first. This ensures that both sides are equal, and helps in finishing out the fuselage. After some time, the other side of the fuselage was cut to match, and both sides were glued up. While attempting to glue the plywood sides on, I popped a few glue joints, trying to square the fuselage sides to the bench top. When I looked along the edge of the table, I realized the top was bowed, and reworked it so the fuselage would come out straight. The sides were covered in plywood and the tail was covered in long gussets, leaving the tail structure open.

The sides were dried and sanded on the top and bottom, and bulkhead was placed across the section behind the seat, making the fuselage look like an inverted boat.

Some crosspieces were placed, and then I attempted pulling in the front around the motor mount. The first thing I realized is the longerons do not want to bend as easy as the plywood sides, which results in the front of the plane resembles a pair of parentheses )( if only one clamp is used. Using two clamps fixes the bow, but farther back along the fuselage, the bow is still present, so when viewed from the end, the plane is not smoothly curved. I have to buy some more clamps, and squeeze in the sides. Once the bottom section of plywood is put on, the curl should be controlled. I think once the wood is bent, it will eventually relax into that shape, and not constantly be under tension. The engine mount seems to be the problem, as it is thinner at the front than the rear, which causes the fuselage to want to bow out a lot more on the sides, kind of hard to explain unless you can look at it. I will have pictures soon.
O.k., so I don't have pictures yet. I went to a fly-in recently, and checked out a max-103 I saw there. Looking down from the front, I saw his plane still had the outward bow at the bottom. It must be something normal to the breed. I glued in some more wood members connecting one half to the other, and pulled the tail end together. Everything is held in place with expensive bar clamps. I moved between this entry and the last one, and found that leaving the fuselage in its clamps for three months while I could not work on it, did wonders for the bowing. The wood relaxed into its new shape, rather than having to be shoehorned into anything else.

I have stapled on the bottom of the fuse, and fit the tail together. Lots of cross braces go into the tail section, for strength. The thousand staples will have to be pulled, prior to the next stage being done. I have retrofit the engine mount base to accept the Rotax 447, even though the engine choice is still a toss-up between it and the 2si 460F-35. It is getting close to decision time. Whatever system I use, I will need to order instruments and parts to fit that particular engine. I plan to go with the EIS from grand rapids, leaving the only mechanical gauge the altimeter. Ultralights with glass cockpits are pretty neat, in my book.

The tail section has a lot of cross braces, and after fitting on the bottom gussets that run the length of the tail, the bottom cross braces go in. After letting it dry, the plane is finally turned upright, and the top part of the tail is done the same way. Next there come diagonals down all four sides, which I have yet to complete. I have what looks like a row of smaller and smaller squares, held together at the corners. Now, the interesting part: The fuel tank. I made a quick discovery the fuel tank is an itty-bitty bit TOO LARGE to slide into the fuselage under the longerons. More than that, it is a trapezoid shape, so turning it one way and then the other did not help in fitting it into the fuselage. So, with no other choice, I cut out a cross member with a hobby saw, the the fuse bent outward enough so the tank would slide in. After some swear words, I was able to clamp up the tank, and position the mounting brackets. The tank mounts inside the fuselage about where the pilots legs go. The grommet and Fuel elbow were fixed into position as well. I hope to God it doesn't leak later, as I will need to order another pack of swear words from ISON to fix the problem. The cross member was glued in place, and I am ready to mount the fuselage top deck and seat sections. The seat base was cut out, and the seat support will be next. I have to go back and pull a thousand staples from the bottom of the fuselage. In interest of timesaving last time I worked on it, I left the staples in place. The engine mount mods are complete, so I can use whatever motor I desire. It appears to have been worth it. Further pictures are forthcoming of the entire project.
I may have to split this into new pages, it is getting a bit long. However.... With most of the cross braces put into the tail section, I decided to test-fit the tail section. This simply means sticking it on and clamping it in place temporarily long enough to take a picture. I like the look, and everything seems to line up right. The tail wheel and empennage hardware need to be installed so I can really check out the fit of everything. The fuse is right-side up for the time being, and balances well with the tail off. The rearmost block for the turtle deck is also in place for fit-up, but will be installed after all cross braces are in.
The gas tank installation is complete, with the exception of the AN hardware to hold the tank brackets to the fuselage wall. Wood screws were stuck in the holes for temporary fit, to hold the tank in place. The top brackets are resting on the tank, and will be glued to the underside of the top deck to hold the tank in place. I plan to put an electronic fuel gauge sender between the brackets, as seeing the fuel level would not be possible. The top deck has been fit and cut to shape, but will not be glued on until the control stick and rudder pedals are in place. It will be easier to finish construction that way.
  The seat base was glued in as well while working on the gas tank. The vertical clamps are holding the rear part of the seat support while gluing, and the horizontal ones hold the front part. The front is cut open for the control system. These were all easy parts to cut and fit, only keeping track of what needs glue and what does not is a bit tough. The seat will be held down by screws, not glue, to allow it to flip up for control system inspection. Undoing six screws will let the entire seat come out The seat has been built, and awaits installation. I have to order more glue and AN hardware first.

While waiting on my hardware order to come, I have begun preliminary assembly of the controls. Not having any RS-801 (UHMW polyethylene), I decided to use 1/4" thick nylon sheet, to cut some bearing blocks from. Wayne at ISON  said it would work fine. These blocks hold down the control stick, and the flap handle, while still allowing it to turn. I have also been confused about rudder pedals. I sat in my plane, and noticed the rudder pedals will have to be all the way at the end of the floorboard. I'm six feet two inches tall. I also did not like the floorboard resting on the bottom of the fuselage, which ISON suggested. Therefore, I will put in a brace under the floorboard, and rest it on that. <br>
The pedals and springs cause some concern, as they will be so far forward, the springs would be awkward to hook up, plus I did not like them anyway. I found a solution at Home Depot. The reason for the springs is the pedals mount to the floor, and the cables run back from the pedals to the rudder. Without some type of spring attached to the bottom of the pedal, they would simply flop over on the floor when I take my feet off. Home Depot has some hinges with springs inside, for self-closing doors. They look like a plain hinge, only where the hinge pin is, the hinge is real thick. Those hinges will eliminate the need for an external spring.
I finally got my metal hardware, and have begun building the controls. I elected to part from the ISON construction plans in one way: I got to the point where I am supposed to glue the top deck on, and the turtle decks. Before going that far, I am putting in the control system for the airplane. It will make things much easier to get to, and to see inside the plane. I turned the fuselage on it's side, and test fit the seat and the floorboard, before putting on the second coat of paint. The flap Bearing blocks have been installed, and the fuel tank temporarily removed. I found the secret to removing the fuel tank, and it works pretty good. The fuel tank is being prepared for having a Westach Fuel Level sender installed. I have changed my mind, and will go full analog on the gauges, because if any one breaks, it can be replaced. If an EIS breaks, I have to send in the whole thing, or buy a new one. The price worked out about even for what I want in the plane anyway.
I finished making the control stick and related hardware. In the picture below, some of the bolts are missing, and not all of the cables are hooked up, but you get the idea. It is a simple, reliable system, with few moving parts. The next step will be to mount the stabilizer and test out the control stick to ensure the proper adjustment and freedom of movement.
Returned to its upright position, the fuselage is undergoing construction of the turtle decks, the final major components. They are mainly for cosmetic and aerodynamic reasons, not for structural integrity. The front turtle deck and firewall also houses the instrument panel and electrics. The rear turtle deck hides some cables, and the first portion of it can be made into a storage compartment of sorts. I am not sure if I will do that or not, but it sounds good. There is scant room elsewhere for stored items, so it seems the best place. The red cable in the picture is the elevator push-pull cable. I have started routing the other wires, that will control the tail wheel and rudder.
I have planned the fuel system, and I am still working on the electrical system. See the motor page for more info on that.... in the meantime, I have added the panel, cut from 1/4" mahogany plywood, and completed the rear turtle deck. The front turtle deck is partially constructed, as I waited until I installed the fuel tank for the last time. Well, I will have to drop the tank once when I put the fabric on, but I'm not taking it out any more, unless something is wrong with it. It is removable, but a PAIN IN THE ASS to put back in. If you look at the picture to the left, through the cutout for the tank opening, you can see a gray handle. That handle is just behind the primer, in the seven or so inch space between the panel and the front turtle deck. I climbed into a max-103 at a fly in, and the pilot there had a handle in about the same place. It helps to steady your balance climbing in. It is a stainless steel drawer handle from Lowe's, with inch-and-a-half #8 machine screws and AN970-3 washers holding it to the top deck. Underneath it is backed up with a six inch block of RS-10.

After removing the clamps and putting in all the rear turtle deck members, the next step is forming the swing-open canopy. I lined the fuselage top deck with wax paper, and cut and fit the RS-10 side members. At the rear side, I added a 1/8 inch piece of plywood as a spacer between F-3 and F-3A, the front curved piece in the above picture. This space will be needed later for fabric thickness on the front and rear. I glued the members up right on the plane, to make sure they fit right. After the glue dried and the clamps were removed, the skin was wrapped in place. It was tough to get on, as it wanted to slip sideways, and after cutting, it did not fit right. I used the bag of swear words I had saved up earlier, and got the skin to fit. I then painted it and let it dry. On the opposite side of the canopy is the hinge which supports the canopy. You can see it here with holes drilled, but prior to my painting the canopy, so it is not screwed in place on the top portion yet.
Here you can see me fitting up the front spar carry-through. The panel was removed temporarily, along with the canopy. The top of the stick is visible, along with the fuel shut-off valve. One the floor amongst the coating of sawdust, is the right rudder cable, prior to swaging and installing the bearing blocks. Under the front turtle deck, just in front of the coiled blue fuel line, is the top of the fuel level probe sticking through the top deck. The plane was cleaned up some, and the rudder cables swaged into place.

After ensuring everything was right, I mounted the windshield in place. For this task you REALLY need an extra pair of hands. Four clamps just does not do it well. I used up my supply of swear words, and will order more from ISON at the earliest convenience. I was able to do it alone at last, but it was not easy by any means. I left the paper cover on the lexan plastic, and will remove it only when necessary (right before the first taxi, perhaps?) to prevent any undue scratching. In this second picture you can see my lonesome fuel gauge, all by itself. The canopy in is place and fits good, the only problem is the latch doesn't fit quite right. The first time I latched it, it gouged a chunk out of the RS-8 longeron doubler. The second time I closed it, the piece chipped off, and now the latch won't hold well. I am going to put a piece of 1/16" steel, about 3/4" wide and 3 inches long, on the RS-8 piece by the latch. The latch will then grab the steel, and the steel will be screwed/glued to the wood. No more latch problems.

No pictures yet, but the plane is on her wheels now. The bottom has been painted, and the fuel drain valve installed. I cut a piece of aluminum plate, 1/8" thick, 3/4" high and two inches long, and mounted it where the latch closes. I feel much better about the canopy now. There is little fuselage work to do, besides cleanup, painting, and panel installation. The motor mount area needs a little finish work, but other than that, it is ready for the motor.
These are pictures of the Fuel Drain port. The left image is inside (obviously) and the right image is outside (again, very obvious). Although it looks like the rudder pedal cable rubs the fuel line, it does not. It is a good two inches away. Two of the wires coming down go to the fuel pump, and the other two are battery leads, which run down and under the floor panel. The curve in the fuel line is there on purpose, to ensure clearance. A hose barb and 1/8 pipe coupler sit on a large diameter AN washer. Outside the fuselage is another large diameter AN washer, which a Curtis type drain valve sits in. The drain valve screws into the coupler, holding the two washers in place with the fuselage floor in between.
I have been working on the flaps, too, and have installed the handle and torque tube. The rudder cable runs close to the handle, and on the plans the brackets were in the same place. It required a small correction in the placement of the rudder cable guide, being no big deal. I could REALLY use a grinder right now, for making the brackets, but I will make due without.

Faced with the task of grinding out lots of metal parts, I purchased a grinder. I found one in a pawn shop for twenty bucks. It runs pretty good, weighs a ton, and is in nice shape. It could use new wheels, but for now these will do. I figured it would save me money in the long run. The Emory cut-off wheels for my Dremel cost ten bucks for a pack of seven, and aircraft aluminum makes short work of them. I ground the flap handle end to a curve, and rounded off some brackets. I also finished cutting out the flap handle notch thing, which keeps the flaps in position. I ground a 1 inch long by 3/4 inch wide strip off my arm too. Watch out if it is YOUR first time with a grinder (don't forget where that second wheel is). The flaps are basically complete. I mounted the handle and screwed it down tight to the torque tube. With it in the full up position, I positioned the flap arm brackets straight up and down outside the airplane, and drilled the first one. Once it was bolted, I checked the position again, and mounted the other bracket. I have to order some AN bolts to finish it off, but it will look nice when done.

While working on the flap system, I also made a quick mount for my GPS. The store-bought mounts cost 30 bucks or more. I made one for the cost of two AN bolts an a machine screw. I took two pieces of scrap aluminum angle, one-inch by one inch, cut 3/4 inches wide. One the cut was done, I rounded of the edges, and drilled a 3/16 hole in the center of each side, four holes in all. I mounted the first piece to the top deck of the canopy, and the second piece, to it. The remaining open hole is for the GPS to screw into. The back of the GPS has a screw hole, meant for a cable attachment, but works just as well for a mounting bracket. Pictures will be forthcoming. Simple and cheap. See the Panel page for pictures and more info on it.
The people at ISON were kind enough at my request to have a red seat belt specially made for me. I am telling you, if you want a company that will go all out for you, call ISON! My seatbelt is shown here positioned, but as you can probably tell, the bottom part was not mounted yet. I forgot to order the bolts, so I just threw the thing over the seat to see how it looked. The next step was to make seat belt cable guides, and mount them, and swage the cables. After much trying on and adjusting, I finally bolted it to the fuselage and swaged the cable. It fits great.

I am getting close to moving the plane. I finally have space which will allow me to have it near me and work whenever the notion strikes. I have removed a lot of the metal hardware and painted it. I used aircraft zinc oxide primer (yellow), and covered over it with Wal-Mart Krylon blue. A bad idea.. I am not sure the two paints like each other. At first the blue scraped off easy, leaving a hard coast of yellow, but after drying for a few weeks, they seem stuck good. For parts that slide over other parts, I polished them with Met-All metal polish. The aluminum shines like chrome. I wish I would have done all the metal work with Met-All. My Harley-Driving friends would be jealous. There is a bit more work to do before moving it, but once done, I can work on the fine details. Ninety percent done, ninety percent to go.

While taking the fuselage off the landing gear, I encountered a slight problem. I removed all the screws, assuming the fuse would sit there until I could lift it off the gear and set it down to one side. I was WRONG. As soon as the last screw came out, the fuse dropped like a rock. I heard a sickening crunch, and wood splintering. At first I was worried I had destroyed my landing gear. I walked around to the starboard side of the plane, and noticed the landing gear was fine, but it was STICKING INTO the fuselage. Not a little bit, a lot! I removed the gear from the hole, and cut away the damaged area. After consulting with the East Tennessee Lonesome Buzzards, and Harold Little at Ison Aircraft, I repaired the problem. I ended up following Harold's suggestion of cutting a piece to fit the hole, and surrounding the inside with a patch. The hole before repair is featured below, as well as a close-up of the rudder control cables attach point. Both cables have one swage complete, but the excess cable removal and second swage have not been done. 


I have started the covering process. With the GAPING HOLE in the fuselage side repaired, the large sections of the plane are almost ready for moving, while the smaller sections (the tail pieces) have been moved already, and are currently undergoing covering. The first section covered was the rudder, it being almost a rectangle. Easy enough. The next section was the vertical fin, which is a bit tougher, to say the least. I had to sand the paint off the glue-down areas because the paint will lift off when the glue solvent is put on. Afterwards I messed with the glue until I could get it the right thickness and spread on the parts without clumping all over the place. My first piece had a wrinkle or two in it, but nothing major, and the second piece came out even better. My last pieces of the tail are the horizontal stabilizer and elevator. The elevator has an electric trim servo inside, so I have to get it working right prior to final assembly and covering, but then I will work on it.

I plan to wait on the covering of the fuse because I still need an engine and BRS chute, and the fabric would ruin sitting unpainted in the sun outside.

Finally I saw the first flight of MK692. Okay, so technically is wasn't a powered flight, but a short tethered glide. Out a window, down a cable. But, she was in the air. It just goes to show you can build a max anywhere, even an upstairs spare bedroom, if the window is big enough. She was transported to her new home, reaquainted with her landing gear, and the tail is now being painted.