Should I use wire (Piano) or wire (Braided) for the Lead-outs???

[Paul Bray]

Hi All,

first ‘real’ post so apologies if this has been covered, I have searched several of the threads here but couldn`t find anything definitive. Also, if I am in an inappropriate section please advise and I will move/ re-post.

I am just ‘dabbling’ in CL and so far I have managed to get a 3 different sized disks going around in a circle on the end of 2 lines, please note that I did not use the word ‘flying’ 😊.

I am now doing a conversion of a 100 cm foam HobbyKing GeeBee following this:- 

http://fesselflug.eu/html/gee-bee-1000.html

mainly because I had the model and a suitable motor lying around unused.

To my question, on the disks I made the lead-outs from 0.8 mm piano wire, Z bend in one end and a loop bent onto the other. Thinking was that 0.8 would be flexible enough to give, reduce the contact area on the wingtip lead-out guides (less contact area) and just be easier to produce. I did have a degree of success with my disks but getting them to aerobat was the problem, loop when I was lucky but that was about it (couple of short videos on YouTube user PaulB121090), could have my ‘stiff’ lead-outs contributed?

I now just have the lead-outs and guides to do on the GeeBee and so obviously I am thinking about whether to again use piano wire or to go for braided steel cable. So, is there a definitive answer as to why one method or the other should be used and if so, why (as in the negative effects of the ‘other’ method) or is it just personal choice??

Any help is appreciated.

Happy New Year,

Paul

[Dave_Trible]

Hi Paul and welcome aboard.  In answer to your question my experience would tell you to forgo solid wire lead outs and go with flexible cable.  You can use .018 controls line cable for small airplanes-up to say .25 size and then .027 cable for anything larger.
We found in the early days the main problem with solid wire is that they get bent where they exit the wing and when you straighten the bend it weakens the wire.  Do that a few times and it may just break off in your hands.  With cable that is no problem.  The only real cable issue can be wearing through where it passes through the bellcrank.  That would take thousands of movements to accomplish in most cases but even so I tie the leadoffs there so that two loops pass through the bellcrank hole so that if one ever gave way it has a backup loop. Also NEVER solder these wraps.  Besides corrosion solder makes for a mechanical 'hard spot' in the cable where the solder ends.  This becomes the place where flex concentrates and will cause the strands to crack.  Instead bind with fine soft brass or copper wire and epoxy.

Dave

[Scott Richlen]

If your airplane has less than a 46 size engine just use music wire.  I've never broke one.  Just use a little care in handling and you'll be fine.

Music wire is much easier to work with and the lead-outs look so much nicer.  I use flexible too, but only on my big planes.

[Dennis Toth]

Paul,
Welcome and Happy New Year. The best choice for lead-out's is cable, you can get bellcrank assemblies with the leadouts in-place from Brodak or Stunthanger Hobbies on this forum, use 4" size (3" will also work). Having said that for years we used 0.040" music wire solid leads that worked fine.  Just make sure to use at least 3 full tight turns around the end to make the hookup loop. Looking at the picture of the GeeBee with the controls open you could get an adjustable tip leadout guide from Brodak that has a plywood frame that would glue to the wing tip (I would use epoxy for this). It has a nylon slider so no need to bush it. If you decide to just make a plywood guide use some 1/8" eyelets to bush where they leads go through the plywood. Set the tip leadouts centered (about 1" apart) 1/2" behind the CG balance point (for CL you should set this at about the 18% back from the leading edge to start, just a little in front of where the bellcrank is mounted in the picture) to start.  Looks like a fun ship, I would set the controls so you have more elevator than flap if you decide to couple them (maybe 2:1 elevator/flap, it has very big flaps).

Have fun and let us know how you are doing with it. Just for information you can check the "list your setup" section to see what others have used for a similar size ship for the timer, battery etc.

Best,   DennisT

[Tim Wescott]

My personal preference is braided, more or less for the reasons given.  I've even gone over to using it on my 1/2-A stuff, now that I have leftover "big plane" control line by the yard.  Looks like a cool project -- keep us posted.

As a rule of thumb for airplane size vs. leadout size, look at the recommended line size in the CL aerobatics rules (it goes by airplane weight), and use leadouts that are somewhere between 1 1/2 times that size and 2 1/2 times that size.

[Randy Powell]

I've always used braided, but my buddy Pat Johnston has mostly used solids. Either is fine, but it's easier to bend the solids accidentally.

[peabody]

Seems to me that Winfred used wire for a long time...until one broke inside the wing, where it had never been bent.
He discovered that there were pits in several pieces of the (K&S) wire that he had in stock.
He switched to cables.....
Have fun.

[Glenn (Gravitywell) Reach]

I'm a klutz and I can no longer deny it....my wife is right and don't any of you tell her that!   So I have gone to using braided exclusively.  I did use solids in the beginning, but I can't tell you how many times I bent them by walking by the plane and not paying attention to how close I was.  Its a pain to straighten them, although I have never had one break because of it.  So in all this rambling I would recommend that you use braided.

[Steve Helmick]

While I'm a fan of cable leadouts, I would happily use solid wire leadouts IF the controls are fully exposed so that you can replace if need be. But only if.  Steve

[Brett Buck]

I now just have the lead-outs and guides to do on the GeeBee and so obviously I am thinking about whether to again use piano wire or to go for braided steel cable. So, is there a definitive answer as to why one method or the other should be used and if so, why (as in the negative effects of the ‘other’ method) or is it just personal choice??

   Use flexible cable, and be careful to treat the end fittings to reduce the tendency to fail at the wrapping points or where it goes through the bellcrank.

     Brett

[Paul Bray]

Thanks for the help.

I was tending to solid ones but now have swing over to braided.

Interesting to see that it is mostly personal preference and not a 'you have to do it that way because....'.

Thanks again

Paul

[Garf]

It seems to be a personal choice.......BUT....I have never used and never will use soild leadouts. I have seen too many planes with a bind in solid leadouts from bending and attempting to straighten the wire.

[Pat Chewning]

Your 0.8mm wire is way overkill (.031") for small models.

I think 0.6mm wire will do the trick (.024").

Yes, stranded wire as shown in the link you provided for adapting the "Gee Bee 1000" to control-line:



And a "Z" bend is not reliable enough with solid wire for the lead-outs.  You need to make a complete secure loop.

[Tim Chenevert]

When I was a kid flying 1/2A stuff, I used wire but now that I am back in it and flying bigger planes I like braided cable. Tim

[PerttiMe]

Your 0.8mm wire is way overkill (.031") for small models.

I think 0.6mm wire will do the trick (.024").

Yes, stranded wire as shown in the link you provided for adapting the "Gee Bee 1000" to control-line:



...

And the text mentions 0.5mm from a fishing tackle shop.

[Paul Bray]

on the disks I made the lead-outs from 0.8 mm piano wire, Z bend in one end and a loop bent onto the other. Thinking was that 0.8 would be flexible enough to give, reduce the contact area on the wingtip lead-out guides (less contact area) and just be easier to produce.

0.8 Was the piano wire lead-outs to used to date, not any suggestion of what size of braided cable that I may consider using.

I had some fishing leaders that I was thinking of using but they are too short, I also have a spool of 0.5 mm diameter (including plastic coating) steel braided so I am going to go with that.

Paul