Controls

Fuel Gauge

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Started working on the electrical wiring and discovered that the EIS 2000 I have only supports a single fuel level input. They sell the EIS 2000 as a two or four stroke model when in reality it does not matter if you have a two or four stroke the difference between the two models is features not engine type. When I build the next airplane I think I will build my own EIS or use the flybox.

So the Grand Rapids folks suggested using a switch so I can select what tank level I want to monitor. After thinking about this for some time I decided this is the best option but that it needs to be implemented carefully. Imagine monitoring the full tank but running the engine from the empty tank. That could result in a bad day. 

In designing this I decided the goals should be as follows: 

  1. The position of the tank selector valve dictates what fuel tank is monitored by the EIS
  2. If the fuel selector valve is in the off position then the EIS should see an empty tank triggering the warning 

The typical inexpensive fuel selector valve is not suitable for triggering some electrical switches. I ended up purchasing a WSM 006-600 jet ski fuel valve on Amazon.com and a couple of 2750017 micro switches from the local RadioShack. 

Fuel valve and micro switches
Fuel valve and micro switches

Using a file I put a flat spot on the knob that was parallel to the flat side of the D hole in the knob. The location of the flat spot is important so if you have a different valve you might need to change the location.

Fuel valve knob modified with notch
Fuel valve knob modified with notch

When the knob is installed on the valve the flat spot should line up with a micro switch roller only when the valve is turned to the left or right tank. This will require the switches to be mounted 180° from one another. I used OnShape.com to make a drawing that I printed out in reverse on toner transfer paper. This will provide accurate centers for the holes and the labels for the valve. 

Putting the switches to their marked locations on the toner transfer paper you can get an idea of how this will work. 

Arrangement of micro switches
Arrangement of micro switches

I varnished a piece of plywood, sanded it smooth and applied the toner transfer. Then the parts were cut out and drilled. A smaller valve support plate needs to be 5/8″ away from the panel so the notch in the knob is just below the plywood. 

Micro switch actuated by notch
Micro switch actuated by notch

On the outside, for asthetics I used 1/4″ X 3/4″ pine. A 1/8″ notch was cut into the outside piece and the valve support set into the notch. The inboard side used a small piece of 1/4″ X 5/8″ pine. Alignment is important so I glued this together with the valve and knob installed to keep everything indexed.

Fuel valve support
Fuel valve support

Once the epoxy cured the switches were mounted using #3 screws and the valve installed. 

Fuel valve, switches and wiring
Fuel valve, switches and wiring
Fuel selector knob and labeled panel
Fuel selector knob and labeled panel

The electrical wiring did take a little bit of planning. I wanted to make sure that should there ever be a malfunction that only a single fuel level sensor would be connected to the EIS. Here is the wiring diagram that does this: 
http://schematics.com/embed/fuel-sender-selector-46440/full

Before takeoff simply turning the valve to all three positions will confirm if the system is functioning properly.

I think this turned out well, looks pretty good mounted on the fuselage side. 

Fuel tank selector valve
Fuel tank selector valve
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Improved Trim System

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I never did like how the spring at the rear of the elevator cable worked so I decided to do something different. Both springs are now attached directly to the stick.

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With no spring in the way installing the elevator safety kit at the rear of the fuselage was much easier.

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I also installed the safety kit at the front.

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Trim System

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Installing the Aeroconversions trim system is really simple. I drilled a 1/8″ hole in the elevator cable bracket and attached a spring.

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The other end of the spring was attached to a washer with a hole drilled in it. I might decide to attach the spring in a different manner but for now this seems like the best solution.

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The other spring will be on the control stick assembly. A hole was drilled in the aileron yoke on the left side and the cable end bolted in place.

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The cable was routed from the adjuster to the yoke where it was terminated with the spring attachment.

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Trim cable and spring

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A hole was drilled in the control stick bracket where the other end of the spring was attached.

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Now the adjuster can be actuated putting more or less tension on the yoke spring.

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Trim adjuster

Updated Dashboard

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My first dash was made from 1/4″ plywood, this was difficult to deal with since most panel mount items are made for a maximum of 1/8″ panels. The problem with 1/8″ panels is they are too flimsy and need additional support. I’ll worry about that a bit later. I started with the same type of plywood used on the fuselage sides, thought the matching color would look nice. After drilling, sanding and varnish I have a nice looking dash.

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Minimax dashboard

The tablet will mount to the four holes in the center. The next problem is making the dashboard stiffer. The first thing I did was cut the perimeter of the original 1/4″ dash.

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The bottom needed to be cut down to 1/8″

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Next I created two support members and glued the three pieces in place.

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I also added a piece of 1/8″ ply to the center mount point.

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The trim adjuster was also bolted to the support brace.

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The result is a rigid dashboard that can easily be replaced should I decide to rearrange/replace the instruments in the future. It also looks really nice.

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Elevator Trim Tab

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Searching the Internet for some ideas for the elevator trim tab lever I stumbled across a much better idea for a trim system than an ugly tab. The Aeroconversions Trim System is quite simple and not very expensive so I ordered it. It works by adjusting the tension on one of two opposing springs. One spring pulls the elevator up, the other down. Adjusting the tension on one spring will cause the control sick to move.

The first thing I did when it arrived was modify it so it can be adjusted easier.  Picked up a few parts from the hardware store.

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Drilled a hole into the trim dial.

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Put it all together and now have a little knob that makes it much easier to operate.

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After climbing in the cockpit to test different locations for mounting the trim dial, I decided that the best location is on the dash. Since I need to use my left hand to operate it the only logical place was the left dash right where my switches are located.

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Looks like it’s time to make a new dashboard, I was not quite happy with the first attempt anyway.

Push to talk

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The push to talk button will allow me to transmit on the air band radio. Having a convenient way to transmit and making it look attractive is my goal.

I used my hobby knife to cut a pocket in the plastic plug that goes in the top of the control sick.

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Control stick cap

The switch was installed and attached to the plug.

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PTT switch

I drilled a small hole near the bottom of the control stick.

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Hole for wire to exit

Added a grommet for the wire to exit.

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Rubber grommet

Finished product looks good.

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Finished control stick with PTT switch

Fuel Tank

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Before gluing the top on I wanted to get the fuel tank mounted. I recall David at TEAM telling me to put fuel in the tank before mounting it since it will swell. About a week ago I put a couple gallons in it and shook it up to ensure the entire inside surface was exposed to fuel. When I checked it today the top and bottom were swollen a little but the four sides were really swollen.

I put the tank and it’s support in the fuselage and placed the top onto the fuselage to ensure everything lined up.

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Fuel tank support

Once I was satisfied that it was located properly I drilled the holes into the fuselage sides and bolted the support in place.

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Tank support bolt

While  the plywood is strong enough to hold the tank I am thinking about adding a plywood doubler around the holes so they will be less likely to get stretched out over time.

This is the first time I’ve had the rudder pedals and the fuel tank in place at the same time and I noticed that they were really close to one another. This had me concerned that my big feet might not fit well so I climbed into the cockpit to check the fit. Unfortunately my fears were confirmed, my toes can get caught on the tank support.

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Tore caught on tank support

This could be deadly, in a panic situation I might not realize my toe is caught on the tank preventing me operating the rudder.

The reason this problem exists is because the rear nose gear C channel raises the floor board 1.25″. After speaking with David at TEAM I cut 1/2″ off the C channel.

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1/2" removed from rear nose gear support

While this made things better it was not good enough. So I also moved the RS-8 tank support back a few inches. A heat gun works great to unglue it.

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Modified tank support

I did not take any pics detailing how the valve and sending unit were installed. It was really simple, drill a 1/2″ hole, insert rubber grommet and then insert the valve. Just make sure you use a Forster bit when drilling the hole so it is perfectly round. If you like leaks feel free to use a regular drill bit.

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Forster bit

If I had the chance to do this all over I think I would have made the fuselage two inches higher.

Completing the nose wheel

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Completing the nose wheel was not too much work. After adjusting the fiberglass rod to get proper ride height I drilled the holes and bolted it to the mount.

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Nose gear fiberglass rod

Next I flattened the ends on the RS-402 struts in the vice and drilled a 3/16″ hole in each one. To ensure both were the same length I put them side by side.

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Nose gear struts

After measuring the needed distance I flattened the other end at a 90° rotation from the first. Marked the holes, drilled them and then installed both struts.

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Nose gear strut mount

The steering bar nylon support was put in place. This was tricky because of the angle.

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Nylon support

The steering rods were threaded and attached to the rudder pedals and steering arm.

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Nose gear steering arm

The rudder pedals were clamped to a board to keep the straight. The steering rods were adjusted until the steering bar was centered. With the nose wheel straight the bolt hole for the steering arm was drilled into the steering bar and fastened in place.

Rudder Pedals

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Now that the floor board is fastened in place I turned my attention to the rudder pedals. The two pedals were cut from RS-591. The curve was cut using the Dremal circle cutting attachment, I doubt my feet will be bothered by the center hole. Once they were cut the hinges were attached and they were mounted on the floor board. Two 1/4″ slots were cut in the floor board to accommodate the nose gear controls.

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Rudder pedals attached to floor board

Next the nose gear steering brackets were fabricated from RS-200. Unlike the TEAM prototype, my 1030 has the floor board sitting on the nose gear c-channel support so I had to make the brackets longer than the plans.

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Nose gear rudder bracket
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Extended brackets

Next it was necessary to cut slots in the fuselage bottom so these brackets can reach the outside. I did this by using the floor board as a guide drilling two 1/4″ holes at the end of each slot.

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Transfer slots to fuselage bottom
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Guide holes for slots

Then using 3/16″ drill bit I drilled a series of holes the between the two 1/4″ holes. It was necessary to make the slots in the fuselage longer than the floor board slots so I extended the holes.

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Holes drilled length of slot

Using the 1/4″ round file I connected the slots and cleaned the edges with a flat file.

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Nose gear steering arm slots

Next the brackets were attached to the pedals and the floor board installed to check fit.

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Rudder pedals with nose gear brackets

This area will be difficult to access once the fuselage top is installed so, according to the plans, I cut an access hole in the front of the fuselage. Again the Dremel circle cutter was handy.

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Dremel circle cutter

I did not make one continuous cut, each half was cut leaving a little bit of material between the two halfs.

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Leave a little connected on each side to ensure you end up with a circle

The cover was installed to check fit.

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Access cover looks great
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Access cover inside

To complete this I fabricated the rudder cable and spring brackets then attached them to the pedals. The front nose gear c-channel was removed and two 1/8″ holes drilled in it. Two springs were installed on the two holes with the other end attached to the pedals.

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Sidings attached to c-channel
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Springs attached to pedals

Since the circle cutter was out I also cut the hole for the foot step.

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Foot step hole

Elevator Cable

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I glued the nose ribs on the left wing, while that was drying I decided to get the elevator cable installed. Once the elevator cable brackets are glued in place I can start varnishing the fuselage.

I first cut the RS-201 bracket that holds the cable at the rear of the fuselage.

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I did not drill the holes for the shoulder seat belt cables because I plan to mount them different than the plans after reading this accident report that will be discussed in a future post. The four mounting holes were only drilled to 1/8″. Once the bracket was in place I match drilled the fuselage using my dremel 90° attachment and a 1/8″ bit.

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I then drilled the fuselage and bracket holes to 3/16″.

Next I routed the cable through the fuselage mounting it to the control stick and rear bracket.

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Using some 1/8″ plywood scrap I cut three brackets with a 5/8″ hole.

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I soon discovered that the bracket at station #5 needed to be made different.

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Holding the cable lower with the larger bracket allowed the cable to rest in the middle of the bulkhead hole so it does not rub when moving the stick.

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Here you can see the other two brackets.

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Lastly two RS-9 blocks need shaped and glued in place just in front of the rear bracket.

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Those were glued in place while the bracket was installed. I then removed the bracket and wiped off any excess glue that got on it. Once dry the bracket was reinstalled.