How To -- Make Your Own Rudder Pedals

By Rob Barendregt

If you are you interested in making your own very accurate rudders pedals with less than $10 worth of material, please read on.

Introduction

Fifteen years ago, when I bought a second-hand synthesiser, I needed a set of volume & wah-wah pedals. Since I couldn't find something I could afford at that time, I decided to make my own. See the pictures on the right.

Now, I am also a flightsim fanatic, and I own a Logitech Wingman Force joystick. However, when flying with this for a few months I was ready for a new challenge: flying without auto-coordination with a separate rudder control. Using the keyboard for rudder control is very cumbersome, and especially when flying helicopters it's not accurate enough. Since I am quite satisfied with my joystick, I suddenly realized: why not use these musical pedals?

And behold, with a little electrical modification and 2 hours of trial and error installing it, it worked like a charm! All you need is a PC with a unused analog game port (joystick port), some pieces of wood, three potentiometers (variable resistors) and some other small stuff. The operation of these rudder pedals is based on the principle of an analog joystick: a joystick axis is just a variable resistor.

In my controller setup I use the Logitech joystick on a COM port, and these rudder pedals on the analog game port (controlling axis 4).

What Is Needed?

• Two potentiometers, value between 20 - 50 Kilo Ohms. Exact value is not relevant since you can calibrate this 'joystick', but their value must be equal and they must be linear (not logarythmic).
• A small trim potentiometer, about 5 Kilo Ohms linear, to calibrate the exact center position of the rudder.
• Two knobs with fixed dial plates (prevents the string and elastic band from slipping off the knob). The diameter of the knob should be about 3 cm, which gives you a pedal swing of 4 to 5 cm. Replace the fitting screw of the knob with a small bolt.
• Two small metal plates (8 by 3 cm). Plates should not bend easily.
• Two vertical poles, wood, 15 cm long.
• Two pedal plates, wood, 20 by 7 cm.
• Two elastic bands and two pieces of thin, strong rope.
• One meter of shielded stereo audio cable.
• Two hinges, a bottom plate, screws, electric wire, a 15-pin male game port connector, etc.
• An Ohmmeter.

Assembly Instructions

• Screw the vertical poles to the bottom plate, the metal plate with fitted potentiometers to the vertical poles, and the pedals to the bottom plate with the hinges.
• Fit the knobs to the shaft of the potentiometers, fixing them onto the shafts with the small bolts 'A'. To obtain an accurate behavior the swing of the potentiometer must be limited to the linear area of the potentiometer (approximately 180 degrees, giving a range of 0.5 to 49 Kilo Ohms for a 50 Kilo Ohms potentiometer). This swing is limited by screws 'B' and 'C'. In the rest position (pedal up) the head of bolt 'A' should rest against screw 'B'.
• Connect the elastic band 'D' between to the bottom plate and bolt 'A'.
• Tie the rope 'E' between the pedal and bolt 'A, fitted over the knob on the potentiometer.
• Adjust the knob on the potentiometer shaft so that in the rest position:
  • The potentiometer for the left pedal 'P-left' has a value of 49 Kilo Ohms
  • The potentiometer for the right pedal 'P-right' has a value of 0.5 Kilo Ohms
• Ajust the rope and screw 'C', so that when the pedal is fully down (resting on screw 'C'):
  • The potentiometer for the left pedal 'P-left' has a value of 0.5 Kilo Ohms
  • The potentiometer for the right pedal 'P-right' has a value of 49 Kilo Ohms
• Press the pedals a few times. The elastic bands and ropes should run smoothly over the knobs. If the pedal pressure feels sloppy, just use thicker elastic bands.
• See electrical diagram. The trim potentiometer 'P-trim' should initially be set to half its maximum resistance. The potentiometers are connected to the joystick connector via a stereo cable. To limit electrical interferance (resulting in jitter of the rudder), solder the cable shield to the potentiometer housing and connector housing.
  In this setup Windows sees the rudder as Axis 4. Pins 3,6 and 13 of the connector must also be connected to pin 1, otherwise Windows indicates the 'joystick' as "Not Connected".

Installation Of The Pedals As A Windows Game Controller

I can only make the description for Windows98, but it should be possible to get is working under Windows95/ME as well.
Unfortunately installation and calibration of these pedals as a Windows Game Controller is rather cumbersome, since Windows does not have a default one-axis controller. If somebody knows a better solution, please inform me. This is how I did it.

You temporarily need another potentiometer 'P-Temp' (any value between 10 and 100 Kilo Ohms), to simulate the axis 1,2 and 3 during calibration. Temporarily disconnect connector pin 3-6-13 from pin 1, and connect 'P-Temp' between pin 1 and pin 3-6-13. Also connect a small make/break switch (default 'break') between pins 2 and 4, to simulate Controller Button-1.

• Connect the pedal cable to the PC game port.
• Click Start - Settings - Control Panel - Game Controllers.
• Add a new Controller: Click Add - Custom, with Characteristic 'is a joystick' with 4 axis and 4 buttons. Name it 'Own Rudder' or something like that.
• Back in the Controller list ('Own Rudder' should have status OK now), click tab 'Advanced' and organise the Controllers such, that 'Own Rudder' has ID 1, and your other flight controller (in my case the Logitech joystick) has controller ID 2. This is important, since for some (to me) unknown reason, FS2000 gives an erratic rudder behavior if this analog rudder has another ID than 1.
• Click the General tab, and click Settings - Calibrate to calibrate the rudder.
  • Calibrate Axis 1,2: center 'P-Temp', simulate a button click with the on/off switch, fully turn 'P-Temp' both sides several times, give button click, center 'P-Temp again, and give button click.
  • Calibrate Axis 3: fully turn 'P-Temp' toboth sides several times and give button click.
  • Calibrate Axis 4: altenately, fully press left and right pedal several times, and give button click.
  • Click Finish.
• Remove the pedal cable from the game port, and remove 'P-Temp'; reconnect pin 3-6-13 to pin 1 again.
• Connect the pedal cable to the game port again; the status of 'Own Rudder' should be OK again.
• Click Properties, and observe the axis indicators in the Test tab. Axis 1/2 should be in the upper-left corner, Axis 3 fully raised , and Axis 4 centered.
  Pressing the left pedal should raise the Axis indicator fully, pressing the right pedal should lower it fully.
• If OK, exit the Game Controller Window.

Note: You can leave the make/break switch between pin 2 and 4 and use it as an additional button. I use it as a Brakes pedal. See picture.

Installation Of The Rudder Pedal In FS2000

This description assumes that you now use a joystick on controller ID 1, with axis 01 and 02 for Ailerons and Elevator control, and optionally axis 03 as Throttle.

Start FS2000 and go into the Options - Controls - Assignments window. Since you had your joystick configured as controller ID 1 (which is now ID 2) you have to redefine the Assignment list for Events and the joystick axes.

• Select the 'Own Rudder' under 'joystick type'; remove assignments for axis 01, 02, and 03, and assign axis 04 to 'Rudder Axis'
• Select your own joystick under 'joystick type' and click tab 'joystick axes'. Assign axis 01, 02, and 03 to respectively 'Ailerons, Elevator and Throttle axis'.
• Click tab Events/Buttons. Assign you button configuration to the proper events (copy them from the 'Own Rudder' list).

Select your favorite Flight, using an aircraft with a visible rudder gauge on its panel (like the Concorde). Go into the Flights - Realism Settings window and deselect the Auto Rudder checkbox. Check that the rudder is exactly centered; if not, adjust 'P-trim'. Since the rudder control also controls and aircraft's nose wheel, you can also check it by taxiing on a runway, with no wind and all Flight Realism parameters set to 'real'. Select View - View Mode - Spotplane, and observe proper functioning of your new rudder (provided your aircraft's visual model supports it).

A Final Word

I know these rudder pedals do not look very professional. The initial installation is very tricky and it needs regular "maintenance" (you have to replace the elastic bands every few months or so), but hey...it's almost for free, and if you have properly adjusted them they are as accurate (and probably better) than some commercially available pedals. It took me about two days to make and install them (and making it was half the fun), and I've been using them for a few years now.

Finally, obviously, I do not accept any responsibility if it shoudn't work or if my description messes up something in your PC or FS2000 configuration. But, if you have any comments, questions, suggestions or need support, feel free to send me an email (please: no large attachments!).

Happy 'ruddering'