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Swaged Studs on Control Cables.

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BrianW

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Victor Bravo recalled - "The one I remember at A&P school was a big pneumatic one that hammered two female dies together around the swage with about the same force (and noise!!!) as a jackhammer "

This seems to have the virtue of compressing the cable with no cable extension at all.
Thanks for the mention.


Brian W
 

karmarepair

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The fittings you want: Stud - MS21259
Check the associated references, especially the Mil-dtl, and I suspect you'll find the data you seek.

In my mis-spent youth I ran every type of swager known to man, and when I get a few moments, I'll tell you about it.
 

karmarepair

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I started out at 17 or so, working for Jensen Marine in Costa Mesa, building up masts for Cal and Ranger production sailboats, and making up the standing and running rigging and lifelines. At that shop, we used an electrically driven Kearney roll swager - like the Loos manual machines, but electrically driven very slowly. We dipped the ends of the stainless steel wire in a little cup of Stockholm Tar before slipping the fitting on the wire and swaging it twice. It was a little slow, and sometimes you ended up with a banana, where the fitting would end up bent.

Later I worked at Forespar Rigging, making rigging sets for all the OTHER production sailboat builders in SoCal. We had a ROTARY swager at that shop, that smacked two dies together with a sort of camming action, while you slowly pushed the wire assembly into the dies. The cable would feed out the back of the machine. It made much nicer, more consistent swages much quicker. That's the sort of machine a previous poster described. Ours was about the size of a Honda 600 and weighed about as much as a backhoe.

THEN we got an ANCIENT punch press, and the dies. NO guards. You held the fitting and wire in your bare hands, said your prayers, stepped on the pedal, and it smacked the dies together; rotate the assembly 90 degrees on its axis, repeat. Fast, scary. It could handle ball ends, and also used this genuinely scary beast on a lot of smaller fittings. Get the fitting cocked in the dies, and it would shower you with stainless steel shrapnel. Wear a face shield and gun muffs if you remember to...

Standing rigging used 1 X 19 wire, VERY stiff. The swage fittings were good for about 95% of the breaking strength of that wire. Aircraft control cable is generally 7 X 32, much more flexible, and lower overall strength, a swage on that wire would be worth 100% of BS.

American made wire was noticeably higher quality than what we usually used from the Far East, and twice as expensive in the late 1970's. You will not go wrong with any made or sold by Loos.

Other end fittings I've used are Electrolines and Norsemans, where the wire gets formed and clamped in a specialized expensive and fatigue prone fitting, sort of like a flare fitting for wire. Not a fan. A nearly brand new Swan had these on the standing rigging, and every single one of them failed a dye penetrant check after one season of ocean racing.

Spelter fittings were not much used in yacht work, but you see them in cranes and heavy rigging. Shove the degreased wire end into a socket fitting, "broom" out the wire, and fill the fitting with lead, or later, with metal filled epoxy.

Then there are Nico-Press crimp fittings. I've put on thousands. There are several ways to screw them up, and they don't work on 1 X 19, but they are relatively quick, and the tooling is cheap. They are frankly all your need for aircraft control wires. Always used with a thimble - an eye is the only end fitting you get.

Then there are Liverpool splices. I worked these a few times. Needs a riggers vice, a Swedish fid, and about an hour and a half. Roughly as strong as a Nico-Press.

I would take a serious look at Dyneema or the other high modulus fibers for control AND structural wires (drag/anti-drag or flying). MUCH easier to work with, lighter. The Bug series of gliders and the Bloop use it with apparently good results. Modern yachts use it for STANDING rigging in place of the stiff 1 X 19.
 

wktaylor

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NOTE. Safety issue...
Swaged or crimped fittings... and onto-the-wire rope... should have a thin unbroken over-coating of 'bright contrasting paint' applied as a 'slippage indicator'... thus...

MIL-DTL-6117 WIRE ROPE ASSEMBLIES, AVIATION, SWAGED TYPE
3.8 Slippage indicator. The junction of the swaged fitting and wire rope will be marked with a durable, permanent paint or similar media to assist in determining evidence of slippage. Marking shall be applied to the wire rope or any abutting jacketing, tubing or other covering. The color of the marking shall be as specified in the contract, order, or drawing. If no color is specified, a color that is clearly visible and contrasting with surrounding elements shall be used.
 

pictsidhe

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Sadly, this has the ring of truth. Pity one has to settle for the Socialist approach to scarce resources - sharing for a fee; rather than the sturdy individualist (Capitalist?) approach of buying an example for sole use. <g>

Brian W
A lot of things would not be possible if we had to buy the tool for everything. What's not capitalist about selling a professional service, anyway?
For a homebuilder wanting to swage perhaps a dozen ends, buying a multi thousand dollar swager is a very, very expensive way to do it, rather than paying ACS a small fee.
I don't think BoKu has his own swager, and he is a kit manufacturer. Or maybe, he just doesn't want half of HBA expecting favours and is keeping quiet about it 😉.
 
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TFF

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Standards are there because before the standard, something broke. Unless you want to set a new standard, it’s really unimportant.

In the US you don’t have to follow standards for a homebuilt. There have been some who have used a regular nico press crimpers on swaged fittings and them slip out. I believe they were used on flying wires and the plane folded up in the air. This was 60s or 70s. I don’t think it did it right away but a couple of years later. Just a time bomb with a random clock.

Properly engineered, I can use shoelaces, might take 500 laces though. Nico press and a swage fitting can be done with reengineering but it’s not going to be the same off the shelf stuff. Who knows what it would take unless you put it into numbers.
 

Bill-Higdon

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Victor Bravo recalled - "The one I remember at A&P school was a big pneumatic one that hammered two female dies together around the swage with about the same force (and noise!!!) as a jackhammer "

This seems to have the virtue of compressing the cable with no cable extension at all.
Thanks for the mention.


Brian W
EAA 292 has one of these devices, watched some of the DH-2 wires being produced
 
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BrianW

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你不会说普通话吗
Ho hum - the question is not whether I (or you) speak Mandarin [nor, referring to your earlier note, whether I was inviting the Wrath of Darwin] - but rather whether a Chinese entrepreneur reads sufficient English; the excruciating explanations provided with Chinese trinkets of the technical sort, to the contrary!
As it turns out a little search effort demonstrates that 1/8 in 7/19 cable swaged by rotary or rotating dies can indeed maintain its breaking strain of 2000 l b or less , whereas a HAAS style safety rail swage on their stud for 1/8 inch cable is good for just 1200 l b - having just two diameters of hole depth for crimp or swage, which possibly contributes to that reduced hold.

Now all I have left to find is how Dyneema lines are terminated - and how the strength of strong plastics (like this one or nylon) is so dependent on freedom from friction and possibly protection from UV?
 

pictsidhe

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Instructions use of Best China Swaging machine.

Insert wire into finger.
Insert finger into swager.
Operate swage lever until finger completely crushed

The Chinese now make most of their own industrial machinery. I work in an American factory packed with Chinese injection moulding machines. Some is big stuff, hundreds of tons. I frequently need to translate the odd bit of Chinese, so have an app...

Dyneema creeps horribly. Pretty useless if you need it to keep tension or length. It's so slippery it's a greasy pig to terminate.

The Darwin comment comment was in reference to the Raptor, which has an ever increasing number of serious issues that are not being addressed.
 
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Hot Wings

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Dyneema creeps horribly. Pretty useless if you need it to keep tension or length. It's so slippery it's a greasy pig to terminate.
Creep is a problem under constant tension but for something like an open circuit rudder cable creep is probably not a big deal. Also the archery group have some modified/treated Dyneema variations that have less creep than the norm.

Vectran has little creep but is not as tolerant to UV as is Dyneema - which is as good as Dacron. Always a compromise. :(

I have run across methods of terminating Dyneema that claim to maintain full strength, but can't find it in my notes right now.
 

karmarepair

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Colligo is the best source I've seen of line (Dux, pre-stretched Dyneema) and fittings for synthetic rigging.
Colligo Marine®. They do NOT make Dux (Dynice does) but they are a big promoter of it.

https://static1.squarespace.com/static/556621c8e4b02628a8d3bde8/t/560f0739e4b0e099a9679a5b/1443825465257/DynexDuxFAQ.pdf discusses stretch and creep. They have ways of dealing with both.

Termination is via a Brummel Splice. https://www.colligomarine.com/s/splicing_instructions_for_web_rev_1_2.pdf

A different rigger who ALSO likes Dux Dynice Dux or SK75 - Rigworks

There is an article in a recent issue of Professional Boatbuilder about re-rigging one of the historic ships at Mystic Seaport, and they PAINT their synthetic standing rigging to keep the sun off it.
 

Orange4sky

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Kearney did make a small roll swager (model 6-5) but it's not in production AFAIK. I found one on Ebay a couple of years ago. It came with 1/16, 3/32 and 1/8 dies and was peviously owned by a sail maker. It does not come with ball end dies but those can be done on a simple hydraulic press with the right dies. There's a hydraulic press swager (Daniels, ATI, etc.) with dies that could be used on a press with some home made tooling.

Kearney 6-5 Swager

Portable Pneumatic Cable Terminal Swager Kit



 

BrianW

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Colligo is the best source I've seen of line (Dux, pre-stretched Dyneema) and fittings for synthetic rigging.
Colligo Marine®. They do NOT make Dux (Dynice does) but they are a big promoter of it.

https://static1.squarespace.com/static/556621c8e4b02628a8d3bde8/t/560f0739e4b0e099a9679a5b/1443825465257/DynexDuxFAQ.pdf discusses stretch and creep. They have ways of dealing with both.

Termination is via a Brummel Splice. https://www.colligomarine.com/s/splicing_instructions_for_web_rev_1_2.pdf

A different rigger who ALSO likes Dux Dynice Dux or SK75 - Rigworks

There is an article in a recent issue of Professional Boatbuilder about re-rigging one of the historic ships at Mystic Seaport, and they PAINT their synthetic standing rigging to keep the sun off it.
Hmmmm... five years life? About dyneema terminals, a google search revealed stubby end terminals for it, in stainless - sounds like this is another recipe for line roulette then.
Painting dyneema with (flexible) paint seems like an available solution to UV failure during their five year life - after all, paint or spar varnish is often recommended for epoxy composite surfaces too.

Thanks for sharing your valuable insights.
 

karmarepair

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What a beautiful tool. That's plenty big enough for airplane control line work.

Kearney did make a small roll swager (model 6-5) but it's not in production AFAIK. I found one on Ebay a couple of years ago. It came with 1/16, 3/32 and 1/8 dies and was peviously owned by a sail maker.



 

karmarepair

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About dyneema terminals, a google search revealed stubby end terminals for it, in stainless - sounds like this is another recipe for line roulette then.
Where did you find them? In the past, I've seen "Spelter" type sockets, using epoxy, designed for synthetic lines, but that S--t, all of it, is slippery, and has low "surface activity", so none of it glues very well, so I'm skeptical.

Electroline has it's style of "suppository capture" fittings for various type of synthetic rope. Synthetic Rope Fittings - Electroline You'd have to ask them if these would work on the Dux/Vectran/Dyneema lines - examples I have seen of these hign modulus line have generally been SINGLE braid (vice Double Braid or "Kernmantle") construction - that doesn't seem to lend itself to this type of fittings.
 

BrianW

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Where did you find them? In the past, I've seen "Spelter" type sockets, using epoxy, designed for synthetic lines, but that S--t, all of it, is slippery, and has low "surface activity", so none of it glues very well, so I'm skeptical.

Electroline has it's style of "suppository capture" fittings for various type of synthetic rope. Synthetic Rope Fittings - Electroline
You'd have to ask them if these would work on the Dux/Vectran/Dyneema lines - examples I have seen of these hign modulus line have generally been SINGLE braid (vice Double Braid or "Kernmantle") construction - that doesn't seem to lend itself to this type of fittings.
Here are some line terminals I spotted:




The "Termination Plate" method is shockingly simple - perhaps when bound or with a shrunk on sleeve.
 

karmarepair

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The "Termination Plate" method is shockingly simple - perhaps when bound or with a shrunk on sleeve.
You are quite right! I think for the teeny line sizes homebuilts require it would be pretty easy to fabricate from bar stock. Installation video
 
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