Boeing 737 rudder pedals construction
I have finally completed my linked rudder pedals (minus interface). I used real Boeing pedals but the linkages started with an idea from Alain Tremblay (thanks Alain) which I modified as I wanted to use gas springs instead of elastic bands for the tension on the pedals.
Well, this turned out to be an ordeal as I am very lousy at visually how things work mechanically and I had to basically try & fail a hundred times before I got them working the way I like them to work.
The gas springs for the brakes were easy enough to figure out, but the gas springs for the pedals were another thing. I finally found a way that works perfectly and the key part was to have one end of the gas spring not attached to anything but still be able to remain in a certain track at all times. I did that by enclosing them inside a tube. The tube itself is attached at one end and is able to pivot.
http://i32.photobucket.com/albums/d3...n/P1020807.jpg
http://i32.photobucket.com/albums/d3...n/P1020783.jpg
http://i32.photobucket.com/albums/d3...n/P1020801.jpg
http://i32.photobucket.com/albums/d3...n/P1020788.jpg
http://i32.photobucket.com/albums/d3...n/P1020786.jpg
This is how it works. When I push on one pedal, the associated gas spring compresses normally and the gas spring on the other pedal is simply pulled out of the tube by the other pedal since it is only attached to the pedal arm and is free at the other end.
When I release the pedal, the centering is done automatically since both gas springs exert just a tiny bit of pressure on the pedals without compressing the gas springs at all, so the pedals always come back to exact center. If the gas springs were attached at both ends, then the gas
springs would both have to be compressed half way at the center neutral position and the center position would be hard to maintain properly unless both gas springs exerted exactly the same tension at the center of their travel. I'm not an expert with gas springs, but I would think this would be very hard to achieve due to different tolerances.
I must say I love the feel of the gas springs. It is always smooth and never jerky at all for both for the pedals and the brakes and I'm very happy with the results.
http://i32.photobucket.com/albums/d3...n/P1020802.jpg
http://i32.photobucket.com/albums/d3...n/P1020804.jpg
http://i32.photobucket.com/albums/d3...n/P1020805.jpg
And now, all I have to do is figure out how to add the pots & interface. Piece of cake! :roll:
More pics here:
http://good-times.webshots.com/album/560928860GxpIoQ
Maurice