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View Full Version : Duel Yokes.. Need your help.



Trevor Hale
04-28-2008, 06:54 PM
Hey Guys,

Please tell me what I am doing wrong.

http://www.mycockpit.org/photopost/showphoto.php?photo=2717

http://www.mycockpit.org/photopost/showphoto.php?photo=2715 (http://www.mycockpit.org/photopost/showphoto.php?photo=2716)

http://www.mycockpit.org/photopost/showphoto.php?photo=2713

I get good response from Pilot to coPilot with positive movement with every little movement. But when I go Copilot to Pilot, there appears to be some slop and the controls slowly go out of sync.

Please help! I am about to go nuts :)

Thanks,

Trev

Westozy
04-28-2008, 09:47 PM
Hi Trevor,

I see you have used the same method as my controls. In your third picture it is hard to see how you have locked the rope to your yoke axle pulley. Is there a problem there? Are you using nylon rope? Nylon will stretch over time. If so, I would dump it in favour of stainless steel wire rope (1.5mm - 2.0mm diameter). I used 2mm SS wire rope and my yokes have been synchronised without any slippage for over two years now, I have never had to adjust it. Also with SS wire rope, it only has to be stretched to take out the slack, don't tighten it up like a piano wire because you're only trying to drive a 10k pot and the second yoke handle. Do you have good bearings on your yoke axles? I used roller bearings, plain bushes may cause excess drag when the wire is tensioned. Roller bearing are really cheap. My first yoke set up had plain bushes which ended up squeaking after a while.

I'm pointing the finger at your yellow rope!

Also see - http://aerosimsolutions.googlepages.com/yokebuild

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

Gwyn

AndyT
04-28-2008, 10:12 PM
Are your pulleys all the same size?
Are they all mounted the same at the same point with the same hardware and bearings?

QF6228
04-28-2008, 10:52 PM
I agree with Gwyn, We have the same setup and found by using the plastic coated steel rope we had slippage, Try using steel cable, It resolved some issues for us.

Damien.

AndyT
04-28-2008, 11:11 PM
The question is why do you get slippage in one direction and not the other? The rope could be the problem, but assuming all else is equal something is not balanced on one side. Finding it is where the fun is.

PaulEMB
04-29-2008, 01:29 AM
I agree 100% on the SS 2mm wire - I have also used this in my setup, including longer runs of wire around the hyd cylinders, and have no slippage for over 6 months - its a little harder to set up, but I found all I needed in the local hardware store.

I also use bike chain for the top of the yoke/axle connection, linked to the wire partway down the column.

Trevor Hale
04-29-2008, 08:09 AM
First off, Thanks to everyone so far fro the help.

The orange rope, may be Nylon, and I will take the suggestion of changing to the ss wire instead.

But the bad news is this. My pulley's do not have any bearings. The have a 1/4" hub and are floating on a 1/4" threaded rod nestled between to nylon nuts. They spin freely however it is somewhat possible that the tension of the wire/string causes friction on the threaded rod.

So what I gather I need to do here is. purchase 6 new pulley's with Bearings on the hub, and replace my clothesline pulley's with them.

Then chance my string to a SS wire rope.

I am ready to rip my hair out on this, but I need to get this sorted before I complete the shell.

Thanks again for all your help.

Oh, and also there is a 1/4" Bolt notched into the top pulley and tightened down, with the string wrapped around it securely, there is no slippage there, but I may need to work on that in a way that is similar to your wire connector hub.

Trev





Hey Guys,

Please tell me what I am doing wrong.

http://www.mycockpit.org/photopost/showphoto.php?photo=2717

http://www.mycockpit.org/photopost/showphoto.php?photo=2715 (http://www.mycockpit.org/photopost/showphoto.php?photo=2716)

http://www.mycockpit.org/photopost/showphoto.php?photo=2713

I get good response from Pilot to coPilot with positive movement with every little movement. But when I go Copilot to Pilot, there appears to be some slop and the controls slowly go out of sync.

Please help! I am about to go nuts :)

Thanks,

Trev

Tomlin
04-29-2008, 09:09 AM
Trev,

It sounds like your CURRENT set up is just like the one I attempted to create about 3 years ago and yes, I too was pulling hair out and finally just gave up on it all. Now after Ive discovered MC.org, I know all the places I was doing it wrong! The roller bearings vs. anything else will in and of itself make life much easier. I was also thinking the nylon coated wire would grip better, but evidently not, as demonstrated by all these guys here.

Best of luck!

Westozy
04-29-2008, 09:14 AM
Hi Trevor,

Your bottom pulleys should be fine just make sure they have some grease on the axles. I meant your yoke spindle axles should have bearings so the yoke handles rotate very freely without any resistance, this will help a great deal.
I've uploaded this pic to show you how I fitted a small brass electrical connector to my pulley to grip the wire. Aswel as gripping the wire it makes for an easy method of aligning the two yoke handles. Undo the screw, align the handles and tighten it up again. If you do this and use 2mm stainless wire rope, your problem will go away!!!

http://www.mycockpit.org/photopost/showphoto.php?photo=2721

PS Guys, as you see from the pic I have my own lathe and I can make custom pulleys or other turned pieces for any member. Don't be frightened to ask, I'm always looking for beer funds, plus postage of course!

Gwyn

Trevor Hale
04-29-2008, 11:42 AM
Thanks Again.

OK, Well that gives me some places to try. I will start with changing the cable, and see if I can add some greese to the pully's. I do not have a lot of resistance on my yokes, but I do have a bit. I will loosen that up, and change my connector on the top of the pulley to match what you have in your picture.

Here is hoping.

Trev

Trevor Hale
04-29-2008, 03:29 PM
Are your pulleys all the same size?
Are they all mounted the same at the same point with the same hardware and bearings?


Yup, All pulley's are the same size exactly. and Mounted in exactly the same spot on both Yokes.

Trevor Hale
04-29-2008, 03:30 PM
The question is why do you get slippage in one direction and not the other? The rope could be the problem, but assuming all else is equal something is not balanced on one side. Finding it is where the fun is.

I wouldn't call it slippage, more like LAG. it is almost like direct drive from pilot to copilot but copilot to pilot seems to have a bit of a lag to it.

I am going to get some new rope and better connectors for my pulley's on my way home today. Here is hoping that I can make this work.

Then I gotta get the gas springs fired up.

Trevor Hale
04-29-2008, 07:36 PM
Done Deal.


Thanks to everyone for all of your help. Success. Gwyn hit the nail on the head. By changing the Orange rope to the SS cable I have no more lag. Every little adjustment on the yoke mm's of a turn either way, causes the 2nd yoke to move the exact amount.

100% perfect. and it is all thanks to you guys.

Trev

xtreme3d
04-29-2008, 07:40 PM
My setup looks almost like yours. I tried using rope and it did not work, one side will work better than the other or not at all. At the end went with wire and all my problems went away. Rope stretches, it will take out some of the force transmited between the yokes. Believe me I was about to pull all my hair as well :).


Keep 'em flying and enjoy the ride!,


Pedro.

Trevor Hale
04-29-2008, 07:54 PM
Thanks Pedro.

I had a different setup before and rope or wire didn't work. But I am happy to say that I am very happy with the setup now. and wouldn't change it for the world. One continuous wire instead of 3 separate wires was the largest difference.

Westozy
04-29-2008, 08:01 PM
Done Deal.


Thanks to everyone for all of your help. Success. Gwyn hit the nail on the head. By changing the Orange rope to the SS cable I have no more lag. Every little adjustment on the yoke mm's of a turn either way, causes the 2nd yoke to move the exact amount.

100% perfect. and it is all thanks to you guys.

Trev

Good to hear Trev, BTW, those little elecrical connectors are great for terminating the ends of the wires on the turnbuckles too as long as the hole is big enough to take the SS wire through twice.

Gwyn

Trevor Hale
04-29-2008, 08:15 PM
Good to hear Trev, BTW, those little elecrical connectors are great for terminating the ends of the wires on the turnbuckles too as long as the hole is big enough to take the SS wire through twice.

Gwyn

I never thought of that actually. I used crimps instead. but great thinking.

Thanks again Gwyn.. truly great advice.

spitfire9
04-30-2008, 01:30 AM
Just a thought.

In the real Convair 580 yoke there is a bicycle chain on a gear that is mounted up by the yoke,, but halfway down the control column,, there are two ss wire ropes fastened to both ends of the bicycle chain.

This allows for no slippage from the gears to the chains when turning the yoke,, yet the ss wire rope is a lot easier to work with to go around the bottom pulleys and connect the Capt. and co-pilot wheels with the slack adjusting turn buckles.
This works without a hitch.

Here is a quick sketch of what I mean.
675

Trevor Hale
04-30-2008, 08:19 AM
Thats one heck of an interesting concept.

Thanks for that :)

jean-yves kotto
07-24-2008, 07:27 AM
Hi everyone, is there any one that can help me with control loading for my B737 NG sim ? Don't where to start

jean-yves kotto
07-24-2008, 07:30 AM
Hi there want to go for an electric motion base (6DOF) any recommendations ? Plus, I am facing another problem for my visual if I go with motion. Need help on that. thanks for replies

AndyT
07-24-2008, 07:35 AM
For motion, I highly suggest you read Jim's site.
http://www.jimspage.co.nz/intro.htm
After that, sit down and draw out how much space you have to build in. Motion requires far more than most people think!

Then, come back here to MCP.org to the Motion section of the forums and read what we have already.
http://www.mycockpit.org/forums/forumdisplay.php?f=76

That should get you going.

Trevor Hale
07-24-2008, 07:48 AM
Hi everyone, is there any one that can help me with control loading for my B737 NG sim ? Don't where to start

Hmmm. Control loading is interesting. I use the gas springs from loading on my Elevators, but it is not adjustable.

Are you looking for something that electronically adjusts during different phases of flight?

Trevor Hale
07-24-2008, 07:51 AM
Hi there want to go for an electric motion base (6DOF) any recommendations ? Plus, I am facing another problem for my visual if I go with motion. Need help on that. thanks for replies

Also, on top of what Andy said, If you want 6DOF your going to be looking at big $$

I would recommend you maybe start with 3, and work your way up. If you are really gung ho with it, the best thing to do is build a model of the system you want using servo's.

Many video's on YOUtube showing peoples models, Better to work your issues out on 100 bucks worth of kit, then 30K of kit, if you know what I mean.

As for the visuals, you will be limited to LCD/Plasma monitors. You won't be able to use projection. Unless you have a really large warehouse LOL.

jean-yves kotto
07-24-2008, 08:28 AM
Yes I a looking for something that adjusts to the different phases of flight

Westozy
07-24-2008, 08:51 AM
Hi Jean-yves and welcome to mycockpit.org,

I suggest you put the same question in a new thread with it's own title and you will probably have more builders see it. I am unable to help with regard to motion platforms.

Westozy