Stripping coaxial wire

rickdagless · 7377

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Offline rickdagless

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on: October 02, 2014, 05:13:08 PM
I'm having a bit of a challenge stripping the coaxial cable in the Bottlenect RCA interconnect kit.  I have one of these ( http://www.monoprice.com/Product?c_id=105&cp_id=10509&cs_id=1050902&p_id=3360&seq=1&format=2 ) coaxial strippers, and it doesn't seem to come out of the box with a proper setting for this type of cable -- but there is a little hex key that allows you to adjust the blades.  But before I go on improvising there's another thing...

As I'm sure most of you are already familiar, the way that this kind of stripper works is by having two blades, spaced about 3/8" apart, one of which is meant to remove the outer insulation while the other removes the inner insulation.  The problem with this is that a decent amount of the copper braided shielding is removed.

What I'm thinking of doing is adjusting the first blade in the stripper just so that it removes a 1/2" cut of the outer insulation without messing with the braided copper shield, and adjusting the other blade so that it's inert.  After this point, I'd unravel and twist up the braided shield as per the instructions and then go in for round 2, by adjusting (by feeling it out) the second blade and then stripping 1/4" of the inner insulation

I'm not really sure of this plan of attack, as it involves me fiddling around adjusting blades, guinea-pigging the wire in the process, so I was wondering if anybody has another more elegant suggestion (maybe a different tool).  Or maybe you think this plan is okay -- either way I'd like to hear!

Vahe Vartan


Offline mcandmar

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Reply #1 on: October 02, 2014, 05:53:07 PM
The way i strip cable with a utility knife is to score the outer rubber without actually cutting through it, then bend the cable and it should split along that line leaving the braiding perfectly intact. Try adjusting your tool out to do the same, then once you have the braiding pulled back go back in and cut the inner insulation.

M.McCandless


Offline rickdagless

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Reply #2 on: October 02, 2014, 08:57:45 PM
Awesome, thank you!, worked like a charm for the outer insulation.

How do you go about removing the inner insulation?  This tool isn't well suited for that as I need to put the wire in pretty deep to get the cut I need and the tied-off braid gets in the way.  Do you use your utility knife for that, too?

Vahe Vartan


Offline mcandmar

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Reply #3 on: October 03, 2014, 04:15:25 AM
The same approach, make a cut almost all the way through, but stop about 1mm form the conductor.  Then you should be able to grab the insulator and give it a gentle twist to break it off.

I do everything with a simple blade, i've had many years of model making to hone my skills so i dont cut my thumb off.
« Last Edit: October 03, 2014, 04:17:14 AM by mcandmar »

M.McCandless


Offline rickdagless

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Reply #4 on: October 03, 2014, 10:37:49 AM
On the money! Thanks for the help

Vahe Vartan


Offline rickdagless

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Reply #5 on: October 03, 2014, 10:46:22 PM
I've hit a speed bump with the braided copper shield.  I unravel the braiding, peel it back, then group all of the wires together and then twist.  After I solder the inner connection, I wrap the twisted up shield around the main metal support of the connector, but the twisted wire just seems too bulky to be able to make a joint which will allows the plastic insulation to slip over.  I tried anyway, but ended up desoldered my work because the joint was indeed too big.  I've tried twisting it up less (so that the bunch of wires is more flat as opposed to round), but then it's challenging to get a nice mechanical connection to the support.

It might just be a technical thing where I need to make a better, smoother joint, but thought I'd shoot back here in case I was missing something that would make this easier -- any tips?

Vahe Vartan


Offline Grainger49

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Reply #6 on: October 04, 2014, 03:06:29 AM
A couple of suggestions.  Try cutting 1/2 of the shield off and twisting the rest.  Then tin it with solder before soldering it to the connector. 

If possible you could drill a hole in the connector common tab and insert the tinned ground/shield into it.



Offline Paul Birkeland

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Reply #7 on: October 06, 2014, 06:03:41 AM
What I do when I make these interconnects is to twirl up the braided copper a bit, then fold it back and over the outer black jacket.  After that, I will be sure the center conductor is stripped a little, slip that into the RCA plug, then check the position of those cable clamps built into the plug.

If the clamp position looks good, I will crimp them onto the braid/cable really pretty hard, usually with very large pliers.  I will clamp down on hard enough that the cable clamps bite into the cable a bit, and won't come off without a lot of motivation.  As far as soldering goes, at this point very little is needed, and the hard crimping will give you some control over keeping the shape small enough for the connector to fit back together.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline rickdagless

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Reply #8 on: October 14, 2014, 12:20:24 AM
Grainger, halving and tinning the shield worked out perfectly for one side, but I think I ended up cutting the braided copper too short for the other as it was difficult to twirl up the braiding and I was having trouble getting the braiding to 'stay on' the connector.  Haven't tried out drilling a hole, yet.

PB, so just to be certain, the twirled up braided copper is pulled back over the Techflex, and then crimped on by the clamps?  So whatever's left of the braid is sticking out from between the clamps, pointing towards the other side of the cable?


Another thing I realized as I was building was that I ought to pay attention to the orientation of the connectors.  It doesn't look like the cable wants to be bent up or twisted, nor could that be good for the soldered bits.

Vahe Vartan


Offline Paul Birkeland

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Reply #9 on: October 14, 2014, 06:31:25 AM
I tend to fold the wire braid over just the coax, then crimp, then let the tech flex pop back over that, but that's just personal preference.

I also tend to use hot glue on these.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Grainger49

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Reply #10 on: October 20, 2014, 12:37:22 AM
Vahe,

Paul's suggestion of hot glue also serves as strain relief.  It protects the connections from being pulled loose.

BTW, I have built a lot of cables.  Most of those hanging in the room behind my stereo are home made.

(http://i244.photobucket.com/albums/gg7/Grainger49/For%20Posts%20Private/DSC03105_zps5adf3d5e.jpg)
« Last Edit: October 20, 2014, 06:23:40 AM by Grainger49 »



Offline rickdagless

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Reply #11 on: October 22, 2014, 10:32:56 PM
Grainger -- ah, so that's what it's for.  Been looking into making a balanced cable for my HD 650's and there was a fellow on some other webpage (http://redsecta.wordpress.com/2012/03/09/soldering-the-cardas-580600650-plugs/) that fills up the connector cups with hot glue.  Looks like I'll be adding a glue gun to my tools.

And very cool on those DIY'd cables!

BTW, I ended up soldering the braided copper to the inside of the common tab and trimmed off the excess; I avoided dealing with the outside altogether.  Maybe there is some issue with this that I don't see, and if there is certainly let me know, but everything seems to be working great and it felt a lot easier for me.

Vahe Vartan