control lines

[John KruziK]

What is the benefit of braided control line over solid line for stunt or sport flying. Thanks John

[Jim Thomerson]

Cables don't stick together. Don't need as much maintenance (I wipe my cables down before, after and between flying, old racing habit.) I've seen cables that people had ignored that were about 1/16 in diameter and still working. Cables don't kink as easily as solids.  Solids virtues are that you can run smaller diameter and they stretch less.   

[Bill Little]

I think Jim said it all

To elaborate on the "sticking", it refers to the lines getting wet and they will "grab" each other.  Can be catastrophic!  Cables, by their nature, are not "smooth" and the water doesn't tend to be able to grab.  Kinda like the grooves on a tires.  Oh, yeah, it doesn't have to be raining, it can just be very humid for this to happen.  Keeping solids very clean, and applying "something" (Rain X ?) does help to keep the "stickage" down.

Cables can get pretty dirty before grabbng starts to happen, but it is, like Jim says, a great habit to get into as to cleaning the lines.  I always "walk them out" with a alcohol dampened paper towel before my officials, and clean them after at least every other flight. 

Solids can, however, give a different level of performance to a plane.  They are by rules allowed to be smaller diameter and have less drag.

[Shultzie]

Braids cable..v/s solid beats goes on and on!
I have always been a strong advocate for utilizing the smallest dia. guage lines. Gary Letsinger...if you are lurking...
Were you involved on that wind tunnel test in the early 70's where we conducted tests of utilzing trip strip wires that were affixed IN FRONT of Wing surface leading edges.

 I can not remember the NASA test but it involved improving the flow over extremely high altitude high aspect light wing loaded wings, that we rigged with long tight strands of various line diameters etc.
 Some of the preliminary findings were that the MULTI-STRAND thin cables were the most effective due to their  varible & uneven-weaved surface that seemed to not only vibrate less but even more alarming the solid lines tended to transmit more noise or vibration, which in turn   caused higher drag numbers, especially when they were stretch too tightly. Tuning them (like one would tune a guitar string was vital to the outcome and consistencies of these tests.
This was perhaps the most fustrating tests that I ever took part in...and it really hurt my dim witted mind at the time. The engineering staff seemed as lost as us model makers at times. Really exhausting and the outcome...if I remember left as many questions as answers..etc.

  After spending weeks adhearing these lines to wing platform models...my hands were so cut bruised and bleeding...I could hardly bend my fingers.
Lucky for me...I was needed to finish a glamour paint job on our 757 freighter model and that allowed my bloody fingers to heal. (But gads...expoxy thinner really smarts and burns like hell...in the teenies of cuts and  abrasions.)
here is a snap shot of that paint job that I did on that force model.

[Paul Smith]

7-strand cables have a lot more flexibilty that single strand.  Therefore, single strand lines can be damaged and made useless by a single kink much easier.

The main advantage of single strand lines is more steel per given diameter, therefore more strength.   Thus, in a Speed or Racing event, you would need only about .014" solids to get the strength of .018" seven-strand.   As  result, these events don't even offer a "stranded" size, just a "solid" size. 

Solids are best left to hard core competitors.  Use 7-strand !! 
Some guys have even taken a step the other way. 19-strand.  Super-flex !!

[George]

IMHO another blessing for control lines is that they are stainless...which brings back an old memory (sea story?) :

Back in the dark ages, when the bronze coated Johnson "Core Cable" lines first came out, many of us switched to them to give them a try. One day...first flight of the year after the peak-winter layoff, I set up to fly. Did the usual, string out the lines, wipe 'em down while looking for kinks, did the pull test, and put 'er up. First time I pulled full up I must have hit the limit and put full force on the up line because the plane went up then started doing outside loops...only the down line going to the plane. After about three or four outside loops, gave it some slack as it was near the ground and it pancaked in and broke the rudder (the rest of the plane was ok). Fortunately I was flying over grass.

Don't remember if they were the core-cables or non-stainless that LOOKED bronze from rust. In any case, the up line had parted in TWO places. Apparently last time I had flown, it was snowing and I had wiped down the lines after the final flight with a wet cloth...the lines had rusted. When I got home I checked my other lines and had to chuck another set also.

I still have one set of non-stainless (solids). They are on a U-Reely. Neither will ever be used. I think I used some of those solids as leadouts for 1/2A.

Do they still make non-stainless lines? All of mine are stainless!

George

[Garf]

In the process of rebuilding several wrecks, I am finding a number of non stainless (rusted) leadouts. I used the method of wrapping leadouts with copper wire and soldering the copper wire to retain it. one leadout broke just at the wrapping where solder had penetrated the leadout wire itself. I thought the wire was stainless and wouldn't take solder. Guess again.

[W.D. Roland]

have a brand new (50yr old?) of johnson core cable copper colored lines--kinda feels like string!
still in their reel/package where they will live forever.

just a nick on solid lines will cause almost imediate failure on a fast rat.
we would run our bare hands down them to "feel" for them and then inspect with magnifying glass...threw away many a set----go stranded-be happy--fly a airplane.


name with held to protect the wookie(he likes solids)