Connecting a real flap handle

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Kaellis991
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Connecting a real flap handle

#1 Post by Kaellis991 »

For my DIY home cockpit I am considering adding a floor mounted flap handle like the one shown below.
My question is directed to those of you who are good at mechanical engineering.

Each notch of flaps will have to actuate some type of switch connected to the controller board.
I’d appreciate any ideas on how you might mount switches on this flap handle and what type you might use.
I’ll have to cut off most of the arm extending below the bracket.

Any thoughts or ideas would be very helpful.

BE528424-D304-44A3-87CB-CA843C5E73AF.jpeg
89FE3CE6-B769-47CB-B2B5-2F0222A32B24.jpeg

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Ralph
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Re: Connecting a real flap handle

#2 Post by Ralph »

Wouldn't it be easier to connect it to a potentiometer? Maybe with a braided cable?

Kaellis991
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Re: Connecting a real flap handle

#3 Post by Kaellis991 »

Ralph,

That gives me an idea I can try.
How would the movement of the handle translate to the rotary movement of the potentiometer.
And would the potentiometer need to be mounted at some specify location on the bracket?

Edit: I think the potentiometer is the way to go and I can picture a possible way to do it.
Thanks
Kirk

JackZ
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Re: Connecting a real flap handle

#4 Post by JackZ »

If I were you, I would use a linear pot instead.
https://www.mouser.fr/ProductDetail/Bou ... gJM-_D_BwE

You connect the arm of the linear pot via a simple metallic wire. Like this you keep the real lever intact with its notches mechanism.
Guess this lever comes from an old PA28, or a DR400?
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Ralph
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Re: Connecting a real flap handle

#5 Post by Ralph »

You can mount it somehow that it rotates. Or a slide potentiometer (be sure that you buy a linear one if you do this, not a logarithmic one). With a slide potentiometer you might need need a spring as well, but maybe not. You can use the brake cable from a bike for example.

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Ralph
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Re: Connecting a real flap handle

#6 Post by Ralph »

As Jacques said :) Linear. Slide potentiometers are often logarithmic, for audio.

JackZ
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Re: Connecting a real flap handle

#7 Post by JackZ »

Ralph wrote: Mon May 23, 2022 7:32 pm You can mount it somehow that it rotates. Or a slide potentiometer (be sure that you buy a linear one if you do this, not a logarithmic one). With a slide potentiometer you might need need a spring as well, but maybe not. You can use the brake cable from a bike for example.
With a rigid piano wire, a return spring should’nt be necessary, I guess, as the movement would be transmitted both ways.
Good point with the linear pot @Ralph !
The longer the pot, the better
https://www.amazon.com/Fielect-Potentio ... NW5M&psc=1
Last edited by JackZ on Mon May 23, 2022 7:41 pm, edited 1 time in total.
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Kaellis991
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Re: Connecting a real flap handle

#8 Post by Kaellis991 »

JackZ wrote: Mon May 23, 2022 7:30 pm If I were you, I would use a linear pot instead.
https://www.mouser.fr/ProductDetail/Bou ... gJM-_D_BwE

You connect the arm of the linear pot via a simple metallic wire. Like this you keep the real lever intact with its notches mechanism.
Guess this lever comes from an old PA28, or a DR400?
It will be a flap handle from a PA28 since my cockpit build is an arrow.
Linear pot sounds like a possible solution as long as it is a linear scale…not logarithmic

Kaellis991
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Re: Connecting a real flap handle

#9 Post by Kaellis991 »

This is a better picture of the mechanism. This may be the one I purchase.
D5CA2C35-5B4F-4279-B0B9-D69C65F569F7.jpeg

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jph
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Re: Connecting a real flap handle

#10 Post by jph »

Yup, you could use linear or rotary pots. I prefer rotary motion as linear ..meaning in this case .. slide ... pots do not like any tilt pressure on the slide tab unless they are really good quality and tend to have a short life. Either way you can use model aeroplane ..radio control type ..linkages for this kind of hookup, or as said, piano wire which is often used with a simple l kink at the ends for location into a drilled hole is perfect here. You can drill a tiny hole in the moving arm that extends below the unit. The closer to the pivot point the less travel so mount it wherever you need and in that case you can use any length of slide pot within reason as you are reducing the throw by altering the pickup point close to the pivot shaft bolt. At the other end you can use a rotary or linear (slide) potentiometer. If a rotary a small piece of scrap aluminium plate drilled to fit over the pot shaft and another tiny hole in the other end of the plate. Plate omly beds to be about 30 mm long or so, make it to suit. It will operate in the same way a servo arm operates when conbected to a rod. You could even use a scrap of thin ply or a scap of plastic. Just epoxy to the pot shaft, or to a scrap knob. You dont need full motion or anywhere near as you are only looking at a few positions, it will be used with analog in and a calue read from the adc. Each flap position will be a greater than or equal or whatever you decide to use. It is very coarse reading.

If you gave a model shop near you then you can buy a bag of servo horns for large servos. These can be made to push onto a potentiometer shaft with a bit of action from a craft knife.

As for the taper, yes linear also as said.
Joe
Joe. CISSP, MSc.

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