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Using bicycle frame for DIY control column parts

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Hi all, I'm going to cross-post this in all the flight sim forums I know...Has anyone had success in using parts of a bicycle frame as the basis for a floor-standing control column?It occurred to me, if you get an old bike, use a hacksaw to cut out the pedal-bearing and a few inches of the frame around it, and remove the pedals from the cranks - you have the basis for a floorstanding control column. Mount the frame on a base, connect a pipe to one of the pedal cranks, connect the other to a centering spring.I'd be building a yoke which rises from the side of the cockpit, then angles over nearly horizontal a few inches above knee height to place the control wheel in front of the user.Does anyone know if this has been tried before?

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This reply is five years late but positive.

Because I am poor I am obliged to build all my own flight controls for my X-plane11 / Air Manager based system. I have a serious medical problem and so my progress has been slow.

I made a yoke out of a wrecked BMX type bicycle (called a Demon Diamondback, or possibly vice versa). The steering head, on the end of the crossbar, is used as the aileron pivot and the crossbar is extended by fitting it into the downtube, everything else being discarded (I did try using the rear triangle and a wheel stripped to the hub as the pivot, but it needed 5kg of lead as a counterweight and was very much in the way). The yoke grip is a 13.5" (dimension carefully researched) length of 22mm heavy-wall plastic pipe and a pair of bicycle bar-end fittings (£7 from Amazon). The ergonomics of this odd-looking arrangement are surprisingly good.

The extended crossbar is mounted at about 45 degrees on a right triangle about a foot on the short sides made of Dexion slotted angle. This triangle is pivoted onto the floor bearer crossbars (also Dexion) on a piece of 10mm stainless studding left over from a resin-injection bolting job, with PTFE washers. This results in something vaguely resembling the captain's side yoke in a DHC-6 but even less glamorous.

The assembly is more or less complete, less electronics, but has yet to be bolted up under the floor of the cockpit (which is on wheels) and adjusted for ergonomic accuracy. Drive for potentiometers to feed Bodnar interfaces is being developed using Meccano pulley wheels, which can easily be drilled out to fit 6mm pot. shafts. Drive must be by spring-tensioned non-stretch cord, like radio dial cord, not elastic bands or O-rings, otherwise a delay is introduced as the link stretches.

I should also point out that anything like this made from Dexion, or any slotted-angle system, is going to be a shocking hazard owing to its dozens of corners, sharp edges and, in this case, shear points; boxing it in is the safest way. My intended solution is a cheap plastic crate with a hole cut for the yoke shaft, upside down over the whole pivot assembly.

Parts of the rotating brake system of the BMX bike are used for spring anchors and stops for the aileron motion. BMX frames also seem to have the steering head closer to 90 degrees to the crossbar, which is convenient.

The elevator motion is resisted by two washing-machine suspension springs and damped by a cylindrical damper from the same source.

A system of force feedback may eventually evolve involving a small computer (like an Arduino) which reads the IAS dataref, squares it for aerodynamics, and uses it to adjust the position of the spring anchors, probably with a motorised leadscrew (the vice screws on cheap Chinese folding workbenches look attractive).

A set of rudder pedals, which by comparison with commercial plasticware is a rather heavy (about 4kg) affair made of 5mm and 6mm thick steel, with big but cheap industrial footswitches (Amazon, £8.20 ea.) as combined pedals and toe-brakes, is also under construction. These footswitches could be used as-is for button brakes but I have gutted them and hope to convert them to proper analogue control.

I have gradually collected a bag of convincingly Cessna-like switches and as soon as  I can afford to will get cracking on the switch panels. Most switches are DT to avoid setting errors, the few ST ones being relay-assisted using small 5V coil telecoms type relays (NB not using the capacitive discharge ST switch trick - I've tried this with a few switches and it doesn't seem 100% reliable).

I'd be very interested in hearing from other DIY controls constructors as I am sure I must be re-inventing the wheel at every turn.
 

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