Doug's shielded wire

[munkeyboy]

I feel dumb for asking, but what is the correct steps to strip, unbraid and solder Doug's shielded wire?   30% of the time I end with a bad run after I've stripped and soldered.  60% of that 30% are problems that arise later.

Getting a clean strip on the inner wire is near impossible.  The wirestripper cuts thru most of the [teflon?] coating, but I end up having to pull/rip the remaining off.  That of course causes issue at the other end, because that coating is slippery and pulls out real easy.

But once I've semi-successfully stripped the inside and outside, and put some shrink tube on the non grounded side,  soldering sometimes seems to cause it's own issues.   The heat or twisting of the loose braiding seems to cut into the inner coating and will short out the connection.

[DuaneOh]

RG174 isn't the easiest to work with. The inner insulator is polyethylene and melts easily so you need to be quick with the iron. I wish it was teflon, you need super high temperatures to hurt that but then it would cost $$$.  I've not had any problems stripping the inner conductor, at 26 awg it is a tiny wire so having a quality wire stripper is very helpful.

[vampwizzard]

I strip the outside first to expose the shield and the inner wire. Then bring the shield off to one side and twist into a wire. To strip the very small conductor youll need strippers that can go that small cleanly. What I wind up doing is using the small electronics kit blade and spade.. the kind you sort of squeeze on the wire then rotate around it. Then it has a little fork you can pull the end of the wire off. I like to heat shrink the shielded portion onto the wire outer insulator to keep it as separated from the inner conductor as possible. Too much heat will melt that smaller conductors insulation and then you're grounded out.

[Mike_J]

I strip the outside first to expose the shield and the inner wire. Then bring the shield off to one side and twist into a wire. To strip the very small conductor youll need strippers that can go that small cleanly. What I wind up doing is using the small electronics kit blade and spade.. the kind you sort of squeeze on the wire then rotate around it. Then it has a little fork you can pull the end of the wire off. I like to heat shrink the shielded portion onto the wire outer insulator to keep it as separated from the inner conductor as possible. Too much heat will melt that smaller conductors insulation and then you're grounded out.

Agree with vampwizzard, what you need to do is expose the shielding without damaging it. Then use a pin or something like it and separate the braids. Once you have done that you twist the wires from the shielding and grab some black wire to use to ground your shielding with. Twist the exposed black wire with the twisted shielding wires and your shield is connected to the wire you are going to ground. Now you must solder them together. Don't get carried away and solder the wires all the way to the interior conductor or you will probably melt the pvc. When you are finished your black ground wire should be going the same way as the center conductor. Will need to heat shrink the cable to make sure none of the shielding is exposed or it could ground out the signal on the jack. Other side is much simpler as you don't need to bother with the ground wire although you still should heat shrink that end as well. Just want to expose enough of the conductor and the pvc covering that has a name I don't remember now. Having a good pair of wire cutters for the smaller gauge wires as has been mentioned and developing a patient technique to unbraid the shielding wires is very helpful to completing this successfully.

[kagliostro]

Our friend Sluckey (and I, because I've plagiarized from him) we use RG316 (teflon isolation)


---


How to






Franco

[Mike_J]

Our friend Sluckey (and I, because I've plagiarized from him) we use RG316 (teflon isolation)

Franco

I use it as well because it is much easier to use. Just cut off the outside jacket, wrap some 22awg shielded wire around the exposed shielding, solder it on. Expose the conductor coated with Teflon, cutoff enough of the Teflon to make a connection and you are done. RG174 will certainly work in a pinch though.

[Mike_J]

Another thing about RG174 and RG316. As I recall they had the same pF rating so the RG316 is somewhat easier to work with but it is more expensive and if you take your time you will end up at the same place.

[munkeyboy]

Awesome,  thanks guys.  I wasn't folding that shielding back and putting a ground wire on it  (nor the shrink tube).  I was putting the shrink tube on the other end tho.   Looks like I need better wire strippers too.   Never have issues with what I have until I mess with this wire.

[EL34]

My board install instructions shows how I do it
https://el34world.com/Hoffman/instructions.htm


Instructions are on the page above

[HotBluePlates]

...  Looks like I need better wire strippers too.  ...

Teflon asserts its own problems when it comes to wire-strippers.  Basically, multiple methods of wire-stripping need to be in your toolbox.

Automatic strippers are great for some things, simple strippers sized to the conductor are good for others.  But sometimes when you need fine control, a razor blade or scalpel is the way to go.  But you'll need to work hard to avoid nicking the conductors, which also means you'll need a lot of practice.

    -  I learned stripping & soldering in a Intro to Electronics course.  We had a graded homework assignment to prep the end of a 2-conductor shielded cable.  The outer jacket had to be stripped back to an exact measurement, the shielding prepped & tinned in a specific way, the inner conductors stripped back an exact length from their ends, and tinned.  Melted or ragged insulation was a fail, imperfect tinning was a fail, wrong lengths were a fail.

     -  Although I already knew (I thought) how to solder, and stripping wires is "simple," it took me 7 or 8 tries to get everything just-so.  Practice is essential, and don't be in a rush.

[Mike_J]

...  Looks like I need better wire strippers too.  ...

Teflon asserts its own problems when it comes to wire-strippers.  Basically, multiple methods of wire-stripping need to be in your toolbox.

With RG316 Teflon I find it necessary to use two different wire cutters to get the job done. One for the outside jacket and shielding and another to cut to the dielectric (the Teflon protecting the wires that are going to be connected). Only had to use one for the RG174. Once I got a system down it is easier to use the Teflon but unless your are wiring these every day the time difference is negligible for someone who builds one or two amps a year.


Notice in Doug's instructions how he doesn't solder the ground wire connected to the shielding all the way to the dielectric (in this case I believe it is PVC). This is important to the success of your cable. Get too close to the PVC and it is likely to melt. Certainly not a desirable outcome.

[munkeyboy]

Notice in Doug's instructions how he doesn't solder the ground wire connected to the shielding all the way to the dielectric (in this case I believe it is PVC). This is important to the success of your cable. Get too close to the PVC and it is likely to melt. Certainly not a desirable outcome.

For sure, I think this plus twisting that braid too tight have been the cause of my failures.

Side note,  I've finally put together I cannot like a post/reply on Mac.  I switch between windows/mac often and can only like on windows.  I'm sure others have already noticed.

Anyways I do like all the replies guys. Thanks!

[scstill]

Our friend Sluckey (and I, because I've plagiarized from him) we use RG316 (teflon isolation)

Franco

Couple of questions....
Why do you heat shrink the inner connector wouldn't the collar heatshrink do the same?
If the braid can reach the ground could you skip the pigtail step?
Is there any available shielded cable with silicone inner (have melted the RG174 inner)?

[EL34]

Solder skills are everything

If you are melting the inner plastic, then you need to adjust how you join the extension wire to the braid