Pulley system

[Radar]

:mad:Hi Yall!

I'm pulling my hair out trying to get this to work. You guys make these things so easy. Man, I must be stupid.

Can someone please look at this and tell me whats wrong.

:roll:Ready to give up.

[mounty]

Hi Radar,

Try emailing Westozy, he's a mech eng. and may be able to help you out.

Rob

[jmig]

:mad:Hi Yall!

I'm pulling my hair out trying to get this to work. You guys make these things so easy. Man, I must be stupid.

Can someone please look at this and tell me whats wrong.

:roll:Ready to give up.

What is wrong? It looks fine to me.

[Radar]

:mad:I May be using to much of a heavy gage wirer?

[Tomlin]

Yes, I do know that I used too heavy of a gauge wire, thinking it would grip better but in the long run it wasnt flexible enough. Check out Westozzie's picture gallery here for an idea of the cable size.

[Westozy]

:mad:Hi Yall!

I'm pulling my hair out trying to get this to work. You guys make these things so easy. Man, I must be stupid.

Can someone please look at this and tell me whats wrong.

:roll:Ready to give up.

That's almost right Radar, you need to twist the wire on one side to make the yokes both turn the same way, your drawing indicates you will have the yoke action opposite to each other. I'll upload a quick sketch I made for someone else, it describes how to lock the wires to your pulleys.

http://www.mycockpit.org/photopost/showphoto.php?photo=1712

http://www.mycockpit.org/photopost/showphoto.php?photo=825

http://www.mycockpit.org/photopost/showphoto.php?photo=622

http://www.mycockpit.org/photopost/showphoto.php?photo=576

Gwyn

[ak49er]

Radar, you could also wrap the cable all the way around the pulley instead of just over the pulley, this will give you positive traction and require less tension. Of course if you do this, you would need to re-think you routing again. .02

[QF6228]

This pulley thing is a massive ball breaker!!!!! We only just got ours working this weekend, and are very happy with the result in regards to the tension a general feel........We also managed to hook up all of the potensionmeters!
Hang in there try different things and eventually it will come together.;)

Damien

[Radar]

thanks guys.

I just niticed that the pulleys on the buttom of my columns don't turn while they are under tension. I will work on that.

[QF6228]

We used wheels off a sliding door to act as our pulleys, they have bearing inside them so the worked a treat...

[Trevor Hale]

thanks guys.

I just niticed that the pulleys on the buttom of my columns don't turn while they are under tension. I will work on that.

Hey Mr. Radar,

Glad to see you back. I have been wondering where you got off too. Did you have a good summer?

Trev

[marius]

Take note that when you turn left and right on one yoke there is a great deal of tension as your top pulley tries to pull the wire in either direction and move the other yoke.

So you need a nice solid setup with the largest pulley you can fit in the column at the top of each column. so it can easily drive the whole mechanism. I used 3mm stainless steel braided wire and found this to work best. Tried the plastic coated 2mm wire but couldn't get it working smoothly with it.

We spent so many hours trying to get it to work right that I lost count at 40. Helps when you don't have the right tools :oops:

We also used 2 tensioners rather than one. Much easier to configure the whole setup. I think Westozy used one tensioner from what I can see in his pics but he is the man when it comes to this sort of stuff.

[Tomlin]

[QUOTE=marius;41744] Tried the plastic coated 2mm wire but couldn't get it working smoothly with it.

QUOTE]

I can second this notion, I thought that bigger wire and coated would be good. It wasnt. When I build the next set, I have much better ideas of what NOT to do this time, plus Im looking into bevel gears for the system too.

[Radar]

Hey Mr. Radar,

Glad to see you back. I have been wondering where you got off too. Did you have a good summer?

Trev

http://www.thefreeemoticons.info/images/faces/bigsarc.gifHey Trevor. Had a great summer at the cottage.

Thanks for all the help guys. I think my problem was with my bottom pulleys not turning. I will work on that.

[Westozy]

http://www.thefreeemoticons.info/images/faces/bigsarc.gifHey Trevor. Had a great summer at the cottage.

Thanks for all the help guys. I think my problem was with my bottom pulleys not turning. I will work on that.

I used pulleys from some old gym equipment found on the roadside, when we have curbside rubbish collections I think half of the crap piled up is old fitness equipment. It says something about us Aussies!!! The nylon pulleys are great for this job.

Gwyn

PS, Cheers Marius!

[Bob Reed]

I have news for you Gwyn, We seem to have a lot of exercise stuff on the side of the road on garbage collection day as well!! So it is not just you folks!

[marius]

Something is going around. I haven't worked out since weekend because I have been too lazy. I better get into it soon as I am not turning mine into another set of flight yokes :D

[Radar]

:mad:Man oh man!!
This is really starting to P me off!
I have it set up like Westozys' pic. When I turn 1 yoke all the way from right to left the other yoke hardly moves? It moves the right way but just inches. I tried with the tension to max , med and loose.

Should I be using a wirer like they have on a 10 speed bikes. The gear changer wirer?

The wirer I;m using is a little less then .50 cm wide. Maybe to big?


I will keep trying.


Thanks Yall

[marius]

If the other yoke moves less then you need to step back and think where your mechanism is not doing its job.

Is it slipping on the pulley you are turning? Are the pulleys the same size on the top of each column?

[QF6228]

Told you its a ball breaker :D

[Michael Carter]

I don't need or use a dual yoke set-up, but I peruse quite a few mechanical and industrial supply catalogs, some as thick as Webster's Unabridged. And yes, I have one of those editions.

If I needed a dual set-up as many of you have, I would have devised and used a chain and sprocket system. This is a fool-proof transmission-of-movement method with no guesswork involved except for the length of chain you might need...and that can be determined and cut to length as long as you buy more than you need.

It may cost a bit more than the cable/pulley system, but it aleviates many of the frustrations that Radar (and I'm sure others have) is experiencing now with slippage and mis-aligned yokes.

There are also rack systems available for the real experimenter in all of us.

[QF6228]

I don't need or use a dual yoke set-up, but I peruse quite a few mechanical and industrial supply catalogs, some as thick as Webster's Unabridged. And yes, I have one of those editions.

If I needed a dual set-up as many of you have, I would have devised and used a chain and sprocket system. This is a fool-proof transmission-of-movement method with no guesswork involved except for the length of chain you might need...and that can be determined and cut to length as long as you buy more than you need.

It may cost a bit more than the cable/pulley system, but it aleviates many of the frustrations that Radar (and I'm sure others have) is experiencing now with slippage and mis-aligned yokes.

There are also rack systems available for the real experimenter in all of us.

We also went through the process of using chains and sprockets, problems we had were...
-The fine adjustment in the chain were hard to achieve considering the size of the links.
-considering the size of the 80mm piping that we were using it was hard to fit the chain and sprocket into and have it turn without scraping.
-actually finding sprockets that fit is hard enough
There was also allot of other factors that marius mite be able to mention that I can't think of right now. I'm sure chains could work well but in my opinion
pulleys are the way to go.
It sounds like your main problem may be at the top of your yokes........Apart from the help I received from Westozy I found this guys setup a great help to
Drop him an Email...

http://users.skynet.be/jcordon/cockpit/colonGal.htm

Damien

[Michael Carter]

Using the chain and sprocket solution may require a bit more engineering on the part of the builder for fastening or mounting methods of the components, but as I said in my above post, slippage is eliminated and alignment would be assured as long as guidlines for chain and sprocket selection are used.

Tooth and chain must be compatible. And a fine enough chain and sprocket selection will yield the best control without slop.

[Westozy]

Chain and sprocket - naaaaaaaaaaaaahhhhhhhhhhhhh! You are attempting to turn a 10k potentiometer which probably requires a pumteenth of a gnat's knacker of torque to turn. A 2mm stainless wire rope correctly fed around quality nylon rollers with a single turnbuckle and cable clamps attached to the yoke pulleys works perfectly. Lubricate all axles including the yoke axle. Leave the clamps loose, tension the wire with the turnbuckle lightly, (you don't need it as tight as a piano wire). When the yokes drive each other correctly, align both yokes horizontally and tighten the cable clamps to lock the yokes together. Fit a linear pot to the cable somewhere, my wires move 45mm to and fro so a 50 mm pot was perfect. I did this two years ago and have never had to recalibrate the set up, it does not slip or go out of whack.

Use the KISS principle for everything, I see so much over-engineering in our galleries where guys have worked 5 times harder than they needed to, some of it is awesome work and I applaud every effort. Just don't forget that you are making an oversized joystick.

I see I need to add yoke heads and column bearings to the Aerosim catalogue.

Capt. Gwyn (Mech. Eng.) Occasional drunk!

[marius]

On a personal level I found the feel of the yoke much better when we used a chain but you can throw KISS out the window with a chain setup. Its much harder to get right.

The cable system is the way to go if you want only a headache instead of a migrane while building.

[Tomlin]

I found that with chain and sprocket, you had too much slop due to the tiniest bit of play that was in each link. By the time the transfer happened, there was a good bit of delay.

[marius]

I found that with chain and sprocket, you had too much slop due to the tiniest bit of play that was in each link. By the time the transfer happened, there was a good bit of delay.

The trick is to get the chain tight and the right type of chain and sprocket combination. Westozy was right in saying that a chain is really not needed just to drive 2 pots.

[PaulEMB]

Hi all,

I just finished a link that uses the best of chains and cable - suggested by Dieter Jakob of Routech. Please, credit to Dieter for the ideas!;)

I used around 18 inches of bike chain around a nylon tension sprocket for each yoke axle, then connected using 2mm steel wire - this gives you the "fixed" part you need at the yoke, and the simplicity of cables, pulleys and tensioners at the bottom. - Probably would be better with two sets of tensioners, but - time will tell, after a few hours of use.

A few pics posted, plus a schematic of the axle, used by Routech for their 737 yokes.

In addition, I added hydraulic cylinders, in line, to give damping, and that nice, well, hydraulic, feeling.

I haven't yet tried in flight, as I'm still getting the interface wires connected, but both on the bench, and in situ, the yokes feel more "alive" than my previous version.

http://www.mycockpit.org/photopost/data/531/thumbs/yoke-axle.jpg

[QF6228]

Paul.
Those yokes look like a great piece of engineering, it go's to show with the right tool and the right skill you basically can achieve almost anything...;)

Damien