Wrapping lines with spiderwire

[Dwayne]

Tried an experiment, I wrapped a line with 20lb Spiderwire and JB weld. I don't have a scale but I pulled almost hard enough to break the line and it held fine. Anyone else tried it?

[Phil Krankowski]

I did the leadouts on my flite streaks I am building in a similar manner.   Instead of JBweld I used a very thin partial layer of hot glue and then heat shrink.  I tested to about 25# and noted no movement.

I did not severely test since I have used crimps, copper wrapped and soldered, as well as (GASP!) simply soldered without wrappings(!!!) in the past.  (the distant past for the soldered without wrappings, this means I'll have to replace lead outs and probably bell cranks on any of my parents' planes that I might repair and fly)  The manner of wrapping with any soft material is superior to crimps.  Solder over wrapping is a pain (I'm not going to argue any other shortcomings, you are probably right anyways) and simply soldering is simply wrong.

Phil

[john e. holliday]

The only time I soldered lines was on my F2C planes years ago.   Had a way of wrapping them so they would hold up to pull tests and flying.   That was only on the plane end of the lines as they usually stayed on the plane.   I would never solder or epoxy lines that are going to be handled much.   I now swage lines and lead outs.  So far they have held up well.   To me a crimp puts a hard cut at the point of the crimp.   Swagging has pressure full length of the tubeing I use.

When I do wrap lines or lead outs with copper wire I have a way of tying it off so it doesn't come loose.

[FLOYD CARTER]

Nothing could be easier than wrapping lines using the "AMA Wrap".  I use 27 ga\ tinned copper wire.  Never had one of these fail.

Floyd

[Motorman]

The AMA wrap is the gold standard why re-invent the wheel. The serving wire goes through the yoke and gets twisted with the other end so it won't unwrap. String and JB weld are you kidding??


MM

[Lauri Malila]

Hi.

First a warning, those Dyneema fibres are very sensitive to heat, so I wouldn't use hot glue with them.
Secondly, Spiderwire and many similar brands are quite slippery thus difficult to lock in place with glue.
So far my favorite line-end wrapping is done with Kevlar thread & cyano. But using thin cotton thread is just fine, too. Kevlar is just easier to wrap tightly without breaking it and a tight wrapping impregnated with cyano remains flexible. I have never had them fail.
I have also used lines wrapped with AMA style, with copper wire. I did not like them at all as the wrapping is too stiff and creates a stress point in root of the line. No matter how carefull I was, I allways ended up with loose strands, especially with those 19-strand lines.
In my point of view, much more important than the ultimate pulling strenght is how they resist fatigue. Fatigue is mostly caused by clumsy handling but maybe the weight of wrap can play some role, too.

L

[Phil Krankowski]

I used Power Pro, which is branded as Spectra.  Spectra does not suffer heat damage till over 500F.  The hot glue and heat shrink are both fully activated at around 300F.  The fiber is stronger than steel or copper.  It wraps easier as well, so I am sure it is tighter.  I am quite confident in my terminations.

I have never had a termination failure with any method I have used.  The only "failure" caused by a termination is when I had a soldered AMA style copper wrapping that the two leads would contact and hang on the rib at neutral because of the terminations.   Short answer to a couple (not so) funny crashes is there is more likelihood of a crash in a new model from the terminations hanging up than any other reason.  I can extend the heat shrink along the cable to prevent all risk of the termination hanging up when assembled. 

I don't like the epoxy, it creates a shoulder that can hang up.  I did use epoxy on a set of cables, and it is OK, easier than solder at least.

Phil

[Dan McEntee]

  If you wrap your lines as per the AMA rule book, you should never have a problem. If done as per the rule book, the "joint" stays flexible. Someone else here already mentioned avoiding stresses. Even if you flow glue on it, you will make something stiff, it will flex the cable at the point where the stiffness ends, and that is where it will break. I don't like crimps for the same reason. I have lost two planes using premade Sullivan lines that broke up inside the factory crimp. The first plane was bad enough, but I knew better on the second one and was just going to get one more flight then redo the ends to shorten the lines or make new ones, and I lost the model on that flight. The line ends need to be flexible. I wrap with copper wire as has been mentioned, and just find a way to tuck the end of the wire somewhere that it won't unravel.  Anything else I feel is un-necessary. That's my 2-cents worth.
  Type at you later,
   Dan McEntee

[Phil Krankowski]

If so many people lament the use of solder, WHY does everything in the AMA rulebook recommend solder?

http://www.modelaircraft.org/events/compreg.aspx
under CL general it recommends solder in the diagrams

Phil

[Steve Helmick]

I've noticed that the copper binding wire and Cres cable seem to grab eachother. Put two tight wraps of 28 gauge bare copper wire on your braided lines or leadouts. Then try to slide the copper along the Cres. That's why it works so darned well. Is that "galling"? I am not sure. Some sort of affinity.

I like to put heat shrink over the binding wraps. Some like to color code their lines and leadouts. It makes more sense to me to make sure your lines are connected correctly.  Steve

[EddyR]

I have not glued any leadouts in years. I use heat shrink tubing and it is a very neat and small.

[Dwayne]

The AMA wrap is the gold standard why re-invent the wheel. The serving wire goes through the yoke and gets twisted with the other end so it won't unwrap. String and JB weld are you kidding??


MM

Not trying to re-invent the wheel, just messin around in my shop. Trying different things is fun. 

[Steve Helmick]

Can't you just go ice-fishing or something?     Steve

[Paul Smith]

We used to crimp lines for AMA fast & slow combat.  It worked OK for the life of the lines, which was generally between 2 and 4 matches.  

Now I've got copper wire secured with heat shrink.

[Dwayne]

Can't you just go ice-fishing or something?    Steve

Or fly R/C?  

[Target]

I would think it should work fine, so long as the line wrap doesn't chafe anywhere.
Sailplane spares are wrapped with kevlar tow, not copper wire, then wet out with epoxy, and they are very strong (and light too).
For sealing that wrap, I would look at 5 minute epoxy, since its a bit rubbery. But hot glue is also a but rubbery, some of it. Then an overcoat of shrink for more chafe resistance. It should work fine, even if it isn't AMA approved.

While the phrase "Why reinvent the wheel" has merit, they never said that before the wheel was invented.....

It is hard to make progress when nobody is willing to try something different.

Be careful flying the plane with the new wrap job, and report back after some use/abuse.

Regards,
Chris

[Lauri Malila]

Still, I think that kevlar is the best option for wrapping, also other things than lines. Much better than fishing lines etc. as glue sticks to it. Kevlar is the industrial wrapping standard in free flight models.
I do not understand what's so special about copper.

Lauri

[Dwayne]

I would think it should work fine, so long as the line wrap doesn't chafe anywhere.
Sailplane spares are wrapped with kevlar tow, not copper wire, then wet out with epoxy, and they are very strong (and light too).
For sealing that wrap, I would look at 5 minute epoxy, since its a bit rubbery. But hot glue is also a but rubbery, some of it. Then an overcoat of shrink for more chafe resistance. It should work fine, even if it isn't AMA approved.

While the phrase "Why reinvent the wheel" has merit, they never said that before the wheel was invented.....

It is hard to make progress when nobody is willing to try something different.

Be careful flying the plane with the new wrap job, and report back after some use/abuse.

Regards,
Chris

Thanks Chris, I'll be heading out next week, and will post a report

[Paul Smith]

While we don't need to reinvent the wheel, there have been improvements. 
Those wood wheels with the iron bands gave a rough ride, in my opinion. 
I have some new ones made of metal, with these rubber balloon things on them.  They ride smoother, but I I'm afraid some of the air might leak out.

[Target]

One advantage to copper wrap that I see is that if there is a fracture in one wrap, the whole thing wont unravel, since the copper has "memory".
That's where an adhesive comes into play with a fiber wrap. Some type of flexible adhesive would be ideal, but a cover of shrink to avoid abrasion is good as well.
As a career seaman, maybe something mechanical like a half hitch every other or third wrap would be a good idea?

I think this non-copper wrap idea has potential, but it needs to be developed.

Regards,
Chris

[Gerald Arana]

One advantage to copper wrap that I see is that if there is a fracture in one wrap, the whole thing wont unravel, since the copper has "memory".
That's where an adhesive comes into play with a fiber wrap. Some type of flexible adhesive would be ideal, but a cover of shrink to avoid abrasion is good as well.
As a career seaman, maybe something mechanical like a half hitch every other or third wrap would be a good idea?

I think this non-copper wrap idea has potential, but it needs to be developed.

Regards,
Chris

Hi Chris,

I don't know if you are a fisherman or not but there is a way to make a wrapping that is neat and clean. It is done when tying flies and it is called the "Whip finish".  We use a sealant (similar to comet cement or finger clear nail polish) to secure the knot from unraveling.

On a similar note rod (fishing rods) guides are wrapped on with the last end tucked into a loop (I use 6-8 lb mono) and pulled under the wrapping to hide the end. Then epoxy is added and the rod is kept moving until the epoxy has set. Clear as mud isn't it!

Good luck, Jerry

[Target]

I used to wrap custom rods about a lifetime ago....
I agree that any of those methods could be used, but the end isn't really my concern, more worried about abrasion and a strand of the outer wrap breaking in the middle, and the whole thing coming unraveled.
So, that is where some half hitches throughout the wrap would be nice, it would limit the unwrapping hopefully enough to prevent the cables slipping before it was noticed.
The seal stuff sounds like a good plan as well.

[Curare]

You should check out the new UV whip finish stuff you can get.

Super quick and easy to use.

[phil c]

I used Power Pro, which is branded as Spectra.  Spectra does not suffer heat damage till over 500F.  The hot glue and heat shrink are both fully activated at around 300F.  The fiber is stronger than steel or copper.  It wraps easier as well, so I am sure it is tighter.  I am quite confident in my terminations.
........
Phil

Spectra is polyethylene  which melts below 200degF.  The processing to and chemistry in Spectra bring the melt point up about 300 deg or so.  I wouldn't use a heat gun around it.  They can easily get well over 300 deg and a Spectra line has very little mass so it will soften and melt very quickly once it gets to that point.

Phil C

[Phil Krankowski]

Spectra is polyethylene  which melts below 200degF.  The processing to and chemistry in Spectra bring the melt point up about 300 deg or so.  I wouldn't use a heat gun around it.  They can easily get well over 300 deg and a Spectra line has very little mass so it will soften and melt very quickly once it gets to that point.

Phil C

Spectra does not melt in boiling water (212F) I think there is a problem with your units.

Because of your post I did reread the data sheet I have and I did make an error, there is decomposition and melting, constrained fibers begin melting at 145C which is 293F, and pretty stinking close to the temperature that the heat shrink is fully activated on the data sheet I have for that(300F, yes, mixed units all the way).  I do not have a temperature for the glue, but it is lower than the full shrink temperature of the heat shrink.

I will go back to copper wire wrappings (and have to buy more fine copper wire) for terminations I will encase in heat shrink.  Those numbers are just too close together.  I will pull test before deciding if I am cutting these terminations apart.  Only one is inside a wing, on an ARF, and accessible.

For epoxy encased terminations, I don't know, since the spectra was much easier to wrap than any copper has ever been.

Phil K