John's Plane Week 9
Instruments, Cooling and Kingposts

August 31, Monday

My flying buddy Mike Perkins, President of the Terre Haute Ultralight Club, took a week of vacation to help me on this project. We stopped in New Harmony for lunch at the Bayou Grill before driving on to Marks where we arrived about 1:30 PM. Mike, who knew Mark long before I did and in fact introduced us, is the guy who brought Mark and me together on this plane building project.

I leave Mike to Mark and enter week 8 in the computer. By the time I get back to the machine shop, Mark has instructed Mike in cutting and drilling tubes and shown him around the machine shop.

Mike and I plan to cut openings in the instrument pod face plate. This plate is one eighth thick fiberglass and needs to be treated with some care. We will need to cut circular openings for three 3 1/8 inch instruments (the air speed indicator, the altimeter and the dual EGT gauges) two 2 1/4 inch gauges (the tachometer and the water temperature gauge) and one small rectangle for the Hobbs meter. We will drill three 1/2 inch openings for the three button sized lamps on the panel which warn the pilot which switches are on (red for the master switch, blue for the strobes, and green for the auxiliary electric fuel pump). The instruments will be mounted from the back so the faces will be flush with the face plate of the pod and they will be very close together, about an eighth of an inch in several places. The warning lights snap in from the front.

I purchase at Bud's Hardware downtown, an adjustable drill for 24 dollars and Mike and I, after drilling pilot holes for each opening to get the placement accurate, begin to drill the first 3 1/8 inch hole. The blade of the drill has no problem cutting fiberglass, but it begins pulling the glass fibers and crazing an area about a 1/2 inch around the circle. We stopped the drill and decided to use the adjustable drill by holding it in our hands. This drill is a heavy piece and easy to hold, so we finished the job this way. Thinking back, I suspect we could have slowed the drill press down and gotten the same effect. The faster speed of the drill pulled the fibers before cutting them, that's how I see the problem.

Later I turn the prepared face plate over to Tom Smith (Smitty's Fabrications) and he applies a primer coat at his shop for me. I'm getting some special treatment from this guy. I spray paint the primed plate a flat black and display it on Marks plasma cutting table:

September 1, Tuesday

This morning Mike and I wire the pod connector. This is a small plastic piece about an inch by an inch and a half which holds up to fifteen pins. Earlier in the project, I wired the other side of this connector using twelve wires leading from the engine and the control panel. We must be careful to match the wires so I get my wiring diagrams all color coded and show Mike the mate to the connector we are working on so we can double check each other as we wire.

Here is a shot of my temporary sketches taped to the wall near my trike. About the only thing that shows up clearly is the box of colored pencils I use to record color codes but you can see you don' need anything elaborate. But these plans are crucial.

We will use scraps left over from the first wiring session and match the color coding on this side of the snap on connector. The first two wires are for the rear cylinder EGT gauge. I check my diagram and tell Mike to find a pink wire with a black stripe to crimp onto the female pin connector and place it in the number 1 opening. I show him you can read the numbers if you get a certain slant of light on the box. I also point out the numbers run in opposite directions from the male pin end so when the two halves are brought together the numbers match up. Wire # 2 is white, 3 is light blue and so on through number twelve. Several times we stop wiring to hold the two halves together to make sure physical reality matches our intentions and theory. Here is Mike at the wiring table.

It is a simple job but new to me. Mike sells electrical supplies over the counter at Kirby Risk in Terre Haute and is familiar with all the concepts, though most of the parts we work with today are minuscule compared to the parts Mike sells.

We want to test the warning lamps and the system they will work through so we connect them temporarily:. You can see the two connector boxes connected and the three warning lamps here.

All three work. Small accomplishment, great feeling. Mike and I look at each other and grin. Before the wiring is finished, Mark calls Mike to help install the starter on my 582. I continue the wiring, pausing now and again to watch them so I will know how the starter is installed. Mark turns down the adapter from a 503 to the 582 dimensions, and when the starter is installed, they call me over to test it. I turn on the master switch and press the starter button. The battery charge is low but it does turn the engine a few times and we are all three pleased with this step forward.

September 2, Wednesday

Mike works on the king posts while I cut and bend tubes for the control stick which will transfer stick motion to the long push/pull tube to the elevator. Mark's design hinges an adjustable 24 inch tube to the stick and hangs the other end to a 12 inch heavy walled doubled tube which pivots from a bearing we installed on the seat support tube. You need to see a picture of this to understand it. Here is the rear of that mechanism:

The 12 inch tube also pivots on the triangular flange at the bottom of the picture. The flange is bolted to the 24 inch tube which disappears between the seats and leads to the stick itself. The lower left bolt on the triangle will receive the long tube that leads to the elevator. This next picture looks down and toward the rear of the trike. You can see the 24 inch tube is sleeved over and bolted to a short tube which is then bolted to the stick. This arrangement allows quarter inch adjustments in length since the holes on one tube are an inch apart and on the other, three quarters of an inch apart.

Mike has been working on the king posts. The MXII Plus will have a screw adjustable king post. Mike cuts the four tubes which will make up the king posts and slides the larger tubes over the smaller thick walled tubes. He drills and rivets the sleeves to the inner tubes. These have quite a heft to them for aluminum tubes, but given their name and the function they serve, they need it. The posts will be joined at the top with two thick but rather small crescent like pieces. Here is Mike drilling the flange.

Mike checks the tubes just before he temporarily assembles them.

Mark presses the end fittings into the two sides of the king post and here is the ready to install King of Captain America III:

My wing parts are all finished but for the two diagonals. Mike cuts and drills them. We both learn how exacting it is to drill a hole through a tube squarely. You must have the dead center of the tube to begin you drill. Best to place the tube on a holder of some kind on the drill press bed. We use the mill as a drill press and use the mill's holders and clamps to hold the tube in place. Then after drilling the first side of the tube you darn well better check that you don't let the tube twist before the bit hits the other side or you will have a hole off center. Now Mike must drill the other end of the tube and the hole must be exactly parallel with the first hole. So we stick a level through the first hole and I watch the bubble as Mike drills the second hole. Sure, it's simple. But exacting. This method with the bubble also serves to drill holes 90 degrees to each other.

September 3, Thursday

I cut two brackets from plate steel, smooth and drill them to install the center aileron bell crank and the teleflex cable that is controlled by the stick's left and right motion. I drill the two holes each in the root tube to install them and the holes to accept the bell crank bearing bolt and the teleflex brackets. These I install temporarily but tightly, using wing nuts so as not to unnecessarily reduce the effectiveness of the nylock nuts which are used for permanent installations.

The teleflex must be located very exactly in relation to the bell crank and I find my first plan is off by an eighth of an inch. I cannot get the bell crank centered. I drill a third installation hole in the teleflex bracket and the angle this creates is just right. I tighten all connections and make final adjustments by tuning the tube end connections at both ends of the teleflex cable to get the bell crank perfectly parallel with the root tube. I remove the brackets and spray them with flat black paint and reinstall it all. Whew. It has been hot today. I have spent over three hours doing this job. But done it is.

This afternoon Mike and I drive to Bud's Hardware for brass fittings for the liquid cooling system. We pick up a tee, a street elbow and a nipple. Bud asks us, "Hey, did you hear about the ultralight crash in Kentucky? Guy's in the hospital." "Yeah," I say, "Did you hear about the Swiss Air jetliner crash?" Ironic, isn't it, that the ultralight incident is bigger in the minds of the non-flying public than such a tragedy as the jetliner crash?

Jim Doyle sweats two of the fittings onto the radiator openings.

After the fittings have cooled, Mike fills the radiator with the garden hose and tests for leaks. Hope we had enough pressure for a good test. I wire brush the fittings and spray paint the area with flat black and Mike and I reinstall the radiator for the last time, I hope.

September 4, Friday

Mike cuts two of the upper tail tubes. Here he is inspecting one.

I spend the morning with the instrument pod. I gather the pod and instruments on the plasma cutting table. The kitten was handy so I use him for contrast. He was born since the project started and so is younger than the project.

I drill the pod and face plate and install one of the two spring loaded connecting brackets. This next shot shows how the instruments will be protected from vibrations.

Behind the bracket attached to the faceplate with springs is a vibration dampening sponge. The bracket is bolted directly to the ends of the lower half of the pod. A similar bracket will be installed on the other end of the faceplate Tightening the bolts on these brackets stretches the springs and lifts the face plate away from the pod. In other words the face plate, which holds the instruments, is hanging from springs, thus dampening vibrations to the instruments.

Mike has been working on the cooling system. He cuts hoses and installs tubes to the tee and the filler cap. We will not use the filler cap on the radiator but install one above the engine which includes a small reservoir.

Mark joins Mike and they finish cutting tubing and we break for lunch.

Today, Mike and I call it a week at lunch time and head back for Terre Haute. This week has gone especially fast for me, although I worked a day more this week than the last two weeks. I'm sure having a buddy working with me every day has made it seem a short week. We finished up several jobs started weeks ago and started and completed several jobs this week.

Thanks, Mike.



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