Dual linked rudder pedals

New dual rudder pedals are completed after a lot of experimentation and adjustment. These are based on Gywn Perrett's version from Aerosimsolutions , however I tried to deviate a little from his design to suit my engineering ability and access to materials. I had great difficulty getting the pedals to track smoothly in the rails until I followed Gwyn's design more closely. Go to the bottom of the page for a short video of the pedals in action.

The basic pieces making up one pedal. Two pergola brackets, 4 bolts and a piece of 12mm plastic 120mm x 70mm. The sizing you can adjust to fit whatever brackets and hardware you can find. I adjusted mine to fit these inexpensive ($2 ea) but very strong (3mm Galv Steel) brackets I picked up at Bunnings. Two 6mm (1/4") holes were drilled at an angle in each plate and 4 holes on each side of the plastic were drilled and tapped to take the bolts.

 

This is a side view of the base plate with 4 tapped 1/4" holes for plate fixing and axle mounting. The inner two holes will bolt the side plates using 1/4" round head bolts and the outer two are to mount the axle bolts pictured above. Initially I just used the two inner holes using the axles as plate mounts as well, however I found you need the axles at the very ends in order to provide adequate longitudinal stability once you put your big fat feet on the pedals.

 

Axles mounted and ready to bolt the side plates on.

 

 

 

Here you can see the pieces making up the rudder, all made from 6mm PVC. The two sides are screwed to the base plate with 6g self tappers. A piece of pine timber and a 50mm (2") hinge support the pedal and offer movement for toe brakes.

 

 

 

The two pedals, one disassembled and the other assembled with slots etc. in the base. 19mm (3.4") dowel is used for the heel support at the bottom of each pedal and they are raised approx 35mm (1 1/4") from the base. The shaping is loosely based on the real PC12 pedals. Picture shows the early prototype with wooden hinge block. This was replaced by plastic and a 70mm brass hinge.

 

A side shot showing the angle of the pedals and the support bracket assembly. The angle was judged by eye and experimentation. The pedal side shape was done using a bandsaw then fine tuning using a dremel tool with drum sanding attachment. The shape was sketched by hand initially then refined. Best to perfect one side then use it as a template for the rest in order to maintain consistency of shape.

 

The underneath rail mechanism with left side assembled and right in readiness. This is 15mm (5/8") aluminium channel mounted underneath the MDF.

 

 

You can just make out the round head bolts holding the side plates on along with the axles. The axles on the outer ends of the base finally solved my smooth tracking problems.

 

 

Ready for bearings and final assembly. The bearings were my biggest stumbling block as it is very difficult to get something suitable without a lathe or other custom manufacturing. I ended up using 12mm plastic knitting needles cut to size which seems to work fine. Click on the image to view dimensional details.

 

Underneath fully assembled and mounted. Two triangular pieces of plastic pivoted in the centre act as an alternating mechanism to move the pedals in opposite directions. An aluminium bar connects to two so they move in unison and springs act as centering. Very effective and simple.

 

A closer view of one side. There was no rocket science to the triangular shape, just equal side lengths and then some hole drilling and routing at the appropriate spots. Bolts with locking nuts anchor to both pedals and screw into tapped holes in the center of each base plate. This allows for easy movement within the slots either side.

 

And the end result. They feel comfortable and move easily and the spring centering is gentle but effective. I elected to mount them on separate boards for ease of removal during construction and maintenance.

 

Rudder and Toe Brake electronics and mechanics.

 

 

 

And another view. No great science in these mechanics just bits of spare metal, wire and some mechano pieces. Some adjustment of pivot lengths was required in order to take advantage of the full range of pedal movement.

 

Here is a short video of the pedals in action. (Please excuse the legs:) )