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Guest kdarling

Idea for DIY rotary similar to Knitter

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Guest kdarling

Hey, friends...There I was sitting, with a plastic gear in my hand, and thinking about the Knitter up/down output rotaries, when it struck me:What if you put a knob on the gear, and let the gear swing a brass flag between two contacts? Turn right, you click-click against the Up contact. Turn left, the Down contact. The flap would also hold the gear in the middle (off) position, just like a detent.http://forums.avsim.com/user_files/6451.gifKev

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You, Sir, are a bodger beyond compare! Brilliant idea! I'm going to have to run one up and see how it works. Could mount a few of them on a plastic backboard, with just the shafts protruding through a faceplate. Turning it just untill you feel resistance would have the effect of holding the switch closed and putting the signal from the emulator into typematic too, great for rapid turning of, for example, a HDG gauge!Also, two gear wheels one on top of the other, slightly staggered, could close two different pairs of contacts with a slight delay between them - which could then be wired to give "Shift-A" type signals.Richard

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Guest kdarling

*laughing* Okay, I had to research "bodger", but thanks!I'm just afraid the contact bounce will be too much, but I'm glad someone's going to try it out. Probably going to take a bit of experimentation with lengths, peg positions, what to use for contacts (nail points?) etc. Might need a flap on the opposite side to help as a detent, too.Thanks again, let us know if it turns out to be a bad idea or not. Might end up having to use magnetic reed relays or something, but that negates any cost savings. Your staggered gears idea is even more brilliant! How about the first gear turning another beside it?Cheers,Kev

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One gear turning another? Hmmm.... ever see the display thy have on the counter of a lot of car parts stores for some kind of sticky lubricant - that has about a dozen gears all turning each other......Richard

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Guest

Gentlemen,What I did in my project was to use small potentiometers , I openned them and removed the stopper inside, so that I can keep the central cursor at the middle without contact with the lateral contact area of it.The lateral contact area I interrupt same openning the track in opposite side of central cursor.Now I can connect the centre to ground or which you like, and the right and left terminals to which you like, when turning right you will connect the central terminal to right terminal to the left side is same thing.Rgds Alberto Kunzel

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Hey, Alberto - if I understand you right though, with your setup you turn the knob slightly one way to get one connection, slightly the other to get the other connection? With Kevins idea though you can rotate the knob all the way round, just like a regular tuning knob and it will give you a series of signals depending on which way you turn it.Richard

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Guest

>Hey, Alberto - if I understand you right though, with your>setup you turn the knob slightly one way to get one>connection, slightly the other to get the other connection?>With Kevins idea though you can rotate the knob all the way>round, just like a regular tuning knob and it will give you a>series of signals depending on which way you turn it.>>RichardHi Richard,Yes,my system works as you described above.Kevins idea is great, I will do one of this using instead of brass flap a micro-switch which operates with a flip wheel and that only actuate in one direction.RgdsAlberto Kunzel

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Guest jmarcure

I tried this method a couple of years ago and never got it to work well. It would jam, not register connects or get multiple connects. I really think my problems were related to the gear size and tooth spacing. I also had some issues with the contact bouncing back and making contact for the other direction. I even tried to add another set of contacts that would disable one side while turning the opposite direction. I had hoped it would solve the bounce back issue. Don

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Guest kdarling

> I tried this method a couple of years ago and never got it to work well. Thanks, that's all good info to know! I'm just beginning to experiment myself (I found an old computer in the basement with lots of little brass grounding strips). You're right about gear spacing. And I see that it probably works better with the pivot pegs closer to the gear than I first thought. I also noticed that _if_ it can be made to work, mounting the setup with the gear edge facing you would make a nice thumbwheel for automatic pilots, etc.Again, maybe it won't work. But I believe that up/down rotaries use a variation of this with two gear subsections that momentarily mesh and press against contacts.Kev

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I had intermittent luck with it last night - fished some gears out of an old VCR and had a play. The shorter the leg of the strip from the pegs to the wheel, the better, except that if you get it too short you exceed the elastic limit and bend the strip.Cannon makes a really small 1/2 circle "navigation switch" and I had the idea of making a flap wheel to press that one way or the other, so I've written to Cannon to see if they can come up with a source for a small quantity order - the switches are only a quarter or so each - in reels of 2,000 :-(Richard

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Guest kdarling

>I had intermittent luck with it last night - Did you put a V-shaped bend at the end, so it would ride in the gear teeth better?>Cannon makes a really small 1/2 circle "navigation switch" and>I had the idea of making a flap wheel to press that one way orCool idea! I know I've seen them surplus somewhere, let me look. Allied Electronics sells them... for about $2 each, which puts you back closer into Knitter territory, thus negating the fun of DIY :(http://www.alliedelec.com/catalog/pf.asp?FN=926.pdfI figure it this way: 20 Knitter at US$3.45 = $69, plus their $20 fee, plus at least another $15 fee to wire the money to them = $104. So a replacement would have to cost much less than $4 - $5 per to make it worthwhile from an economic standpoint. Not counting the cost of our time, of course .Also, obviously a PIC based solution would be cheaper, etc etc. But where's the fun in that?!Kev

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Guest LeoL

"Also, obviously a PIC based solution would be cheaper, etc etc. But where's the fun in that?!"Ahem...cough cough! I had fun?! :-hah-Leo

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Guest kdarling

>> "Also, obviously a PIC based solution would be cheaper, etc etc. >> But where's the fun in that?!">> Ahem...cough cough! I had fun?! :-hahOh c'mon, Leo, you know you did! Why else did you stay up all those nights?!Just like I spent several nights writing a gauge to control an LCD screen. Couldn't buy it, had to build it, what could be more fun!Yeah, okay. Maybe pulling teeth would be. But hey...Kev

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