Double Bass aircraft cable and knot tying

[robobass]

A few notes on bowden cables, aka aircraft cables.

Cycle brake cables (inners) spring to mind as a suitable source, come in both steel and stainless steel and are about 1/16" diameter. They are cheap and any cycle shop will have them. ...

Sounds workable, but I think they have fewer strands = less flexible, and might be pre-greased. My SS cable is not expensive, has 133 strands, and is vinyl coated, so I think is much easier to deal with. I like the bike shop nibs idea, though. Do they need to be soldered? I thought they were usually just crimped with a pliers.

 

[delta7fred]

Sounds workable, but I think they have fewer strands = less flexible, and might be pre-greased. My SS cable is not expensive, has 133 strands, and is vinyl coated, so I think is much easier to deal with. I like the bike shop nibs idea, though. Do they need to be soldered? I thought they were usually just crimped with a pliers.

If you've found something that works that's great. I just thought when I saw aircraft cable mentioned that brake cable inners were not too far removed.

Yes they are not that flexible but gear shift cable is a bit more flexible, but still pre greased.

The little end covers/nibs are just crimped with pliers. The manufacturers usually use a proper crimping tool that has 3 jaws so makes a really neat finish.

Soldering is an alternative to the sleeves, but anything that stops the ends fraying out and spearing you is good.

 

[beginagain]

I cant imagine how hard this stuff would be to cut with pliers, quite hard probably, if you have a set of bolt cutters then use those, it helps with frayage reduction to. I watched the young man at the store struggle with the special machine they have for cutting and it did a terrible job and fanned out all the strands.
Thx

 

[KUNGfuSHERIFF]

Let it fan out slightly and cut it strand by strand.

 

[beginagain]

I noticed this morning that a .22 cartridge casings fit perfectly over the
the eight inch aircraft cable, very nice.
B

 

[Jeff Bonny]

I cant imagine how hard this stuff would be to cut with pliers, quite hard probably, if you have a set of bolt cutters then use those, it helps with frayage reduction to. I watched the young man at the store struggle with the special machine they have for cutting and it did a terrible job and fanned out all the strands.
Thx

Sorry if I'm beating this to death but I've cut a real lot of wire rope and know what works and what doesn't. Bolt cutters and even new side cutters will only squish the cable and make a real mess of it. A $35 Park Tools CN-10 cable cutter is available anywhere bicycle tools are sold and will work like a charm on small gauge wire. If you have a dremel tool (or even a drill gun will work) use a small zip disk. However you cut it though do a single tight wrap of PVC electrical tape and cut through that so the cable ends you create don't fray when you make the cut.

 

[beginagain]

In my bolt cutters defense they are brand new and three feet long, it may have helped. Taping the wire up is an excellent idea.
B

 

[fdeck]

My tool of choice for bike cable is a compound tin snips. I guess it's the closest thing to buying yet another bike tool.

 

[Jake deVilliers]

Hmm - I cut SS cable with my old 'Made in USA' Channel Lock side-cutters or the Kleins, whichever I find first!

 

[james condino]

A $35 Park Tools CN-10 cable cutter is available anywhere bicycle tools are sold and will work like a charm on small gauge wire.....

This is a brilliant tool to have on hand in the shop; use it once and you'll never go back to a lesser tool. It works fantastic for tailwire cable and strings. Since it is designed as a true cable cutter, it cuts on four points at once- the end result is very crisp and tidy with no fraying or mess to clean up.

j.
www.condino.com
www.kaybassrepair.com

 

[bbass408]

The Crosby clamps are standard in the world of cable as are aluminum crimps. The Crosby is kinda large so I do wonder about buzz. Another possibility is a "Tiller Rope Clamp" (Google it). All of these are available at Home D. Total string tension on a 3/4 bass with normal tuning is almost exactly 250 lbs. (varies w/string type, etc., but I've never seen anything over 300) - way below the breaking strength of 1/8 galvy cable. I'm a little concerned about 1/16" cable since that will put very concentrated pressure on the saddle. I'm not sure of the weight specs on the different clamp types, but all have been used on contrabasses successfully. Many tailpieces have two vertical holes in the back for the "gut" cable. This would make it hard to use the cylindrical clamp with the grub Allen screws pictured above as that would kink both cables at the clamping point since they feed in from both sides. A clamp that keeps the cable ends parallel seems better (like all the types mentioned above). Lastly, if you don't trust one layer of shrink tube, add a second (perhaps larger diameter) after you shrink the first. They used shrink tubing on Apollo rockets. It holds up pretty good.

I play, build electric and acoustic basses and guitars, and have been a s/w engineer for a long time. None of those credentials are worth diddly on this topic, but I have been doing some research.

 

[robobass]

... Many tailpieces have two vertical holes in the back for the "gut" cable. This would make it hard to use the cylindrical clamp with the grub Allen screws pictured above as that would kink both cables at the clamping point since they feed in from both sides. A clamp that keeps the cable ends parallel seems better (like all the types mentioned above). ...

I don't understand. How does a cylindrical clamp not keep the cable parallel (and concentric)? How is it that the other fasteners you mention would be better? Please explain.

 

[DoubleMIDI]

The clamp on my tailpiece wire is between saddle and endpin.
One entering from the saddle side and the other from the endpin side into the clamp.

 

[james condino]

What is the proper name for the aluminum ferule thingy with the two threaded crimping screws that Robo showed in post #4 and does anyone have a specific supply source like MSC or one of the industrial supply houses rather than paying $15 every time I buy one repackaged from the big luthier supply houses? The aluminum looks great and I like the lower mass much more than brass. I'd like to see one in titanium.

condino.com
kaybassrepair.com

 

[Greg Clinkingbeard]

I've always used the aluminum thing that has a cross section like a figure 8. One end of the cable goes one way and the other goes in the other. I flatten it somewhat and adjust the length. Once that's done, I whack it to death with a hammer. I've always gotten the after length within a few mm of the target. They are cheap but do the job.
With tailpieces that have the vertical holes, that thing fits up behind the tailpiece. On my Kay with the holes coming through the front, the ferrule is between the saddle and endpoint. Shrink wrap covers the cable ends.
I'd certainly try the fancier methods, mainly for exact after length tuning, but what I do gets damn close, is cheap and secure.

 

[bbass408]

To Robobass:
I should have looked at your pics more closely. I now notice that two cable widths can go into the cylinder -- in the same direction if necessary and can tuck behind the tailpiece if there's a cavity there. I also found these "tiller rope clamps" to be an interesting alternative too. They have little ribs that cross the cable direction -- like a properly crimped aluminum ferrule. I think that's a good idea. I made a loop of cable, attached a loop of rope and put all my (200+) weight jumping up and down and it didn't budge. It can be easily adjusted too.

All of this stuff is available for next to nothing at Home Depot...
The "Tiller Clamps" are also called "Flush Cable Rope" clamps. They sell a 3/16" version which works on 1/8 too (as tested above ): $2.75 for two.
Figure eight aluminum ferrules in 1/8" size: $1.48 for two plus two "stop ferrules" which you probably won't use.
Crosby cable clamps for 1/8 or 3/16 cable: Not sold separately online but less than 1.00 each. Might want to wiggle and buzz since it's the widest of the choices.

Cable is about 35 cents a foot -- including stainless. Get extra because their cutter is horrible and you'll have to recut.

 

[keiranohara]

James, I would be afraid of the screw deforming Al. Its a clamp you really dont want to slip, so the tendency is to make it really tight. Deformation of the clamp and wire rope really limits the adjustable (also why I avoid cup point set screws). I make my own out of Stainless (I'll weight the assembly tomorrow). Tend to install with about 30mm of play to tune the tailpiece. This adjustable really is the winner against the swagging option (gave my swagging tool away). Ti would be pricey and wear out tooling faster for maybe 20g of savings.

 

[james condino]

Stainless steel would be nice.

As someone who has been riding custom titanium bicycle frames for 20 years (love my helixed Lynskey!!!!!!), properly configured, it is an incredible material at any price. For the smaller instruments, I make all of my adjustable truss rods out of it and I make my own double bass bridge adjuster posts out of it, and my 1" OD oversized hollow Ti endpins. It destroys cheap tools fast, but higher quality tools are fine and worth the effort.

 

[robobass]

SS or Ti would be nice, but Al works fine. I make mine up with 10mm rod and a 4.4 mm hole and use M4 SS set screws, so you get four threads, which holds the weight of two adults. That's for 1/16" wire. For larger cable I naturally use thicker rod. I do work SS and TI on my lathe occasionally, but for this part it would take a lot more time, and just doesn't seem worth it.

 

[keiranohara]

Dome head set screws and a relief hole apposing it make for a strong lockdown on the 3/16 stainless wire rope without marring it up .