• How To Build Rudder Pedals

    How To...Build Rudder Pedals

    By Harold Crowell

    My Rudder Pedals

    Since flying Flight Simulator, I have always wanted to know what it would be like to fly using pedals. I didn't know it could be so economical to build your own and was under the impression that commercial pedals were the way to go. Over the past couple of years, documentation became available on the Internet - in particular FlightSim.Com - about building rudder pedals. For operation, some used hinges and others used drawer slides. Some were quite fancy and some were quite crude. All had one thing in common - (I think) - they all worked, and like beauty, it is in the eye of the beholder.

    So, one might ask "why another 'how to' on rudder pedals"? Simply put, I believe that the world of Flight Simulator is a world of not only those who would like to fly, or a world of those who can and do fly; it is also a world of ideas - new ideas or revised ideas. It is a world where one can learn to do many things never attempted before by many individuals. Summing this up, it is a world of learning and doing and enjoyment. For this reason, I present this article to any and all who are interested.

    The rudder pedals that I am presenting here are quite unique. They employ a built-in source of friction or drag to give the impression of some sort of "force feedback". They operate on the "slide" principle and as one pedal is pushed ahead, the other is pushed back very similar to that of a real airplane. They have a very smooth feel and give a new dimension to flying everything from the Cessna to the "heavies".

    A certain amount of "carpenter" work (and I use the term quite loosely) is required and access to a table saw is an asset (or access to a friend that has one). I am not a great woodworker, so if I can do it, I feel that most anyone can.

    I am sorry that I do not have any photographs of my pedals at this time. I feel that I have provided sufficient documentation, sketches and drawings to easily enable reproduction of my rudder pedals by anyone. If you need more information or clarification on an item, email me.

    The Components

    My rudder pedals are built using several components. These consist of:
    1. Main Base -- the "foundation" of the rudder pedal assembly
    2. Main Base Extensions -- provides a place to "hide" most of the mechanics
    3. Rails -- the units that hold and guide the pedal bases
    4. Pedal Bases & Retainers -- the items which will hold the rudder pedals
    5. Pedals & Support Angles -- self explanatory
    6. Control Arm -- links the two pedals together
    7. Pot/Pulley Bracket & Support -- holds the two pulleys and the pot support
    8. Pot Wheel -- turns the pot in relation to pedal position

    All of these components are illustrated on the drawings pages. As well, they will be illustrated in each sections write-up. Electrical connections will be provided in the "connections" section.

    What's A Pot?

    The term "Pot" comes from the word potentiometer which is nothing more than a variable resistor. It is not unlike the volume control on your radio or stereo. In this case, when a rudder pedal is turned, by means of mechanical linkage, the pot is turned. This sends a signal to your computer game port on axis 3, which by software control in the computer and Flight Simulator tells the rudder to move a certain amount in a certain direction. The pot for these rudder pedals is a 250K linear pot and should be available at any electronics supply outlet.

    Drawings Page 1

    Drawings Page 2

    All Parts On Hand

    All of the individual components should be made beforehand and assembled following my directions. This eliminates the "building - making - building" syndrome. Label all of your parts with masking tape for easy identification.

    OK - Let's Go!

    The first components that we will deal with are the main base and the base extensions. When assembled, you will have a box 14" wide x 16" long x 3" high with an open bottom. All of the "mechanics" are in the box out of sight, out of harm.

    There are several methods of making the slots:

    1. Router
    2. Making the holes then cutting with a jig saw, or
    3. Setting the rip fence on your table saw at 2-1/2" and making the outer cuts on each side of the main base, resetting the fence to 2-3/4" and making the inner cuts on each side of the main board. Next, drill the holes and finish with a hand saw - this was my method. Let's just say there is no wrong way as long as the job gets done and the center of each slot is 2-5/8" in from the 16" edge of the main base and centered on the 16" edge.

    The base extensions are fastened to the main base with white glue and three evenly spaced 1-1/2" #6 flat head wood screws (hereinafter called FHWS) into each extension from the top of the main board. (Refer to Drawing Page 1, Figure 3).

    Now we will install the four rails - outer ones first. These are the rails that are flush with the edge of the main base along the 16" edge. They are fastened in place with glue and 1-1/2" #6 FHWS evenly spaced. Being careful not to try to place a screw in the same location as any of the screws holding the edge base extensions. (Refer to Drawing Page 1, Figure 4).

    Now it's time to make the pedal bases ready for installation. This is quite simply accomplished by sticking four furniture leg pads as shown on Figure 4 and Note 1. These pads are quite readily available at most stores like Woolco, Wal-Mart, Zellers, Canadian Tire, etc. They come in packages of 24 or so and are made of a heavy felt-like material and are cut to 1" disks, which are about 1/8" thick. One simply removes the protective plasticized paper backing and sticks them into position. Sometimes they are sold in strips and I have no reason to believe that a strip along each long edge of the pedal base would not work as well. Also, I have seen this material sold in sheets about 3" wide and 6" long. If this is all you can get, you can cut your own disks, squares or strips.

    Having applied the sliding material, I would suggest you temporarily apply about four layers of 1/2" masking tape to each outside edge of the pedal bases. This tape, when removed, will provide a bit of clearance between the pedal base and the pedal rails.

    Do not remove this tape until instructed to do so as it provides the alignment necessary for the 5/16" dowels to be added later. The holes in the pedal base and the retainers are drilled for a tight fit of the 5/16" dowels (Note 2 of Figure 4). Now insert the pedal base under the lip if the outer rail with the sliding pads down and on the main base and center it along the 16" edge of the main base - in other words, in its neutral position. Now apply glue to one of the inner rails and align it on the main base so that its upper lip is over the edge of the pedal base. The ends of the rail should be flush with the front and rear of the main base depending how accurately you cut the rails. Screw them into position with three 1-1/2" #6 FHWS. Remember I told you not to remove the masking tape yet? This is why...you must now re-check the position of the pedal base and be sure it is centered along the rails - you know - in its neutral position. Now, from below, mark the outline of the slot onto the pedal base above the slot. Remove the pedal base (it may be sort of stiff at this time but that is OK. Remove the layers of tape.

    Slide the pedal base back into position being careful not to scuff off any of the sliding disks. Try sliding the base back and forth a bit while positioned in the rails. It may be necessary to remove the pedal base and sand the upper edge of the pedal base where it contacts the rail lips until a reasonable resistance allows a smooth sliding action. I suggest that you remove the pedal base and rub the top edges with paraffin wax. As well, rub the area on the top of the main board where the pads slide on it.

    Try the pedal action again. Once satisfied, carry out the above procedure for the second pedal/rail assembly.

    Now, remove both pedal bases and find the exact center of the marked slot's outlined length. Mark a point 1-1/2" away from each side of the centerline but centered between the two edges of the slot. In other words, you should have two positions marked on the bottom of the pedal base, which are 3" apart and in the center of the pedal base and the center of the slot of the main base. Now, center punch the two marks and carefully drill a small pilot hole right through the pedal base. Be careful to keep the hole aligned perpendicular (right angles) to the base. Enlarge the holes so that the 5/16" wooden dowel fits the hole TIGHT. Cut two lengths of dowel 2-1/2" long. Slide the prepared pedal into position and tap in the dowels from below up through the slot in the main base. This should allow a travel of the pedal 2-3/4 inches from each side of neutral. Total travel should be 5-1/2". Repeat above for the second pedal. The dowels should not contact the edges of the main base slots at all. If it does, the offending edge of the slot should be sanded until it does not touch. Still referring to Figure 4, tap the retainer over the dowels for each pedal so that is close to but NOT touching the bottom of the main base. I have called these items retainers because that is what they were in my initial design. They simply prevented the pedals from falling out when the main base was inverted. Now, the redesign of the rails prevents the pedals from falling out, but I kept the retainers simply to serve as strengtheners for the dowels. They lessen the chance of dowel breakage if the pedals are slammed hard forward or back. The holes should have been drilled for a tight fit of the dowels. This will allow for disassembly if that is required. When tapping the retainer into position, you may have to provide some backing for the dowels in the pedal base to prevent them from being pushed through.

    The Control Arm

    Referring to Drawing Page 2, Figure 6, the control arm is installed so that the two rearward dowels of the pedal base assembly are positioned in the end slots of the control arm. A hole is made in the main base directly below the hole in the control arm. The hole in the main base should be a tight fit for a piece of 5/16" dowel. The hole in the control arm should be 5/16". A 2-1/2" length of dowel can be inserted through the hole in the control arm and tapped into position in the main base. Glue can be used where the end of the dowel fits the main base if necessary. Next, cut a 1" square of 1/4" plywood and drill its center with a hole that is a tight fit over the end of the dowel. This will prevent the control arm from falling out when the main base is right side up. This control arm causes one pedal to travel back as the other is pushed ahead. Work the pedals by hand and locate the source if any binding takes place and eliminate it by sanding, etc.

    Pot Pulley Bracket And Pot Support

    The pulleys that I was able to get are small (approximately 3/8") enclosed type and are made of metal. The mounting "eye" for the pulley is at right angles to the pulley wheel. The type of pulley you are able to get will depend upon their exact mounting scheme so you will have to use a little ingenuity here. (Refer to Drawing Page 2, Figure 7.)

    The pot pulley bracket is made from hardwood 1-1/4" x 1/2" and is glued and clamped into position on the underside of the main base so that it is centered along the inside edge of the front base extension. I have tried to the best of my ability to depict the mounting location in Figure 8. The ends of the pot/pulley bracket should be in line with the dowels of the pedal base assembly. In my case because of the way the pulleys were made, I had to mount the pulleys at the ends of the bracket before gluing into place.

    Drill the hole in the pot support to accept the threaded bushing. Push the bushing through the hole, rotate the pot body so its terminals will be accessible and secure with the nut supplied with the pot.

    HINT: you may have to remove a layer of the plywood in the area of the bushing if the bushing is not long enough to allow the nut to be turned on. Mount the pot and support assembly into the notch of the pulley bracket so that the pot body is between the support and the main base. Glue and screw as shown in Figure 8.

    The Pot Wheel

    You must provide a setscrew for the pot wheel to lock it into position on the pot shaft. I simply cut a small screw to the proper length and hack sawed a slot in the end of it for tightening with a screwdriver. Use the same size screw to turn it into the wooden wheel to cut the threads for the setscrew.

    Initial Alignment Of The Pot

    Before the wheel is placed on the shaft, rotate the pot shaft fully clockwise. Note its position. Now turn the pot fully counter-clockwise. Note its position. Now, center the pot as closely as you can by turning to its half way travel point. Now carefully slide the pot wheel over the shaft with the off centered setscrew hole toward the pot. Tighten the setscrew and mark a line on the pot and the pot mounting bracket so you will know where the center of travel point is.

    Adding The Control Line

    The control line should be a strong preferably braided material. I happened to have a spool of kite line sleeving so used that. A piece of fishing fly line would be excellent.

    With the rudder pedal assembly inverted, I securely tied the end of a length of line to the front dowel on the right hand side. I then fed the end straight ahead and through the first pulley. I continued around the pulley wheel in a CCW direction two times. The end was fed through the second pulley and then securely tied to the front dowel on the left hand side pulling the line quite tight before tying.

    Very carefully move the rudder pedals from the neutral position to their maximum position one way then the other. This should cause the pot to turn nearly to its extreme in both directions.

    The Electronics

    Flight Simulator needs to see a voltage change signal on axis 3 of the game port. This voltage change will be the result of a varying resistance caused by the rotation of the pot in the rudder pedal assembly. Axis 3 is connected to pin 11 of the game port. The supply voltage (+5v) is available at pin 9 of the game port. So, our wiring need only consist of a single pair from the rudder pedal box one wire being connected to the center (wiper) terminal and the other wire being connected to the proper end terminal. I say the proper end terminal because if the wrong end terminal is used, you rudder action will be reversed.

    A Word About Toe Brakes

    Although I have not included toe brakes, I plan on doing so in the near future. For this reason, even though only a single pair of wires is required for the rudder, I used a 4 pair wire - just for future additions. If you are sure you will not want to add the brakes, go with the single pair. In this case you can use any small connector capable of connecting two wires. I planned for the future and used all DB15 connectors.

    Connections, Connections!

    They say a picture is worth a thousand words so have a look at the following diagram: It is a "Y" adapter and this device is not unique to my system. It is required when connecting more than one device to your game port.

    Adding The Rudder Pedals To Windows

    The following instructions assume you have a CH Products Flight Yoke - either a Virtual Pilot or a Virtual Pilot Pro. The procedure to add your rudders should be similar with other yokes.

    From My Computer and Control Panel, double click (or otherwise open) The Gaming Options or Game controllers program.

    Here it is and this is what it should look like. If you already have a controller (joystick, yoke or other) installed, remove it. Click the Add button.

    Welcome to the Add Game Controller window. Scroll down the list until you see the CH Virtual Pilot or Virtual Pilot Prow. (I am running Win98 with the updated CH VPPro driver). Be sure to check the Rudder Pedals Window. Now click OK.

    This window confirms that Windows has found your controller/rudder pedal combination by the "OK" message. If you have a "Not Connected" or "Unknown" status, there is something wrong with your wiring. Check it out.

    Now, you must tell Flight Simulator that you are using rudder pedals. Here is how to tell Flight Simulator 2000 and 2000 Pro:

    From the menu (if in full screen mode, you have to press Alt first, select Aircraft, then Realism.

    On the Realism Settings window, be sure auto-rudder under flight controls is NOT checked.

    Click the checkmark to return to Flight Simulator. Now to visually inspect your rudder to see if the pedals move it, go to Spot Plane View and position the spot plane behind but slightly above your Cessna 172 or 182. Zoom in close. Move the rudder pedals to see if anything happens. If the rudder is moving, go to Setting Neutral Position section.

    If the rudder is NOT moving try this:

    From the menu again select Options then Controls then Assignments

    At the bottom of this window, click Reset defaults then click the checkmark to exit.

    Try looking at your rudder via the spot plane again. It will be moving. Go to the Setting Neutral Position section.

    Setting Neutral Position

    Start taxiing your plane where it will not collide with anything. Make sure you have the rudder pedals in the neutral position. Now, invert the rudder pedal assembly and hold it on your lap. Loosen the pot wheel setscrew and using a small straight blade screwdriver, turn the shaft one way or the other to cause the aircraft to taxi in a straight line. This is easy to see on a long runway. Once the aircraft taxis straight, retighten the setscrew and you are done.

    Final Comments

    There may be a learning curve as far as using the rudder pedals is concerned. There may be a tendency to over steer as the turning radius is quite tight as compared to a yoke. There also seems to be a tendency to grab for the yoke wheel to help turning - forget it...the yoke does nothing on the ground. I suggest some taxiing practice to get the feel of using your feet to steer; after all, this is how the real ones are steered.

    Accomplishing your taxi skills, now try a take-off. LOOK OUT! Don't over steer going down the runway. The rudder is a good size and has a LOT of control especially with the help of the nose wheel. When you are airborne, wiggle the rudder and see what effect it has. To turn, you have to use the rudder AND the ailerons. Keep the "dog in the house" (the little ball centered in the turn rate instrument). Then try some landings - see how you can easily realign the nose of the aircraft with the runway. Most of all have fun and good flying!

    Harold (Harry) Crowell
    nbhcrow@nb.sympatico.ca