Forums

Unsolderable wire?

Started by Bob E. January 19, 2014
I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's 
almost like it's dissipating the heat faster than I can apply it. With both a 
temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally 
tried. The solder will barely melt when touched to the braid opposite the 
iron. 

I've applied some Kester rosin paste flux as well using my trusty Kester 
60/40 lead-based rosin core solder. No joy. I'm not holding the braid against 
the PCB now, I'm just trying to tin the braid and then deal with melting the 
2 solders (on the PCB and the braid) together later. 

My first attempt--before I realized that I was overheating it--I melted the 
dielectric insulation. 

The mesh is made from some silver-colored braid which I thought is tinned 
copper but now I'm of the opinion that it's steel; it's certainly not 
aluminum. There is also foil which is probably aluminum but I've trimmed that 
back and it's not part of this frustrating process right now. 

What's the trick to getting this braid to take solder? I've never seen this 
before. 

Thanks.

On Sat, 18 Jan 2014 20:22:18 -0800, the renowned Bob E.
<bespoke@invalid.tv> wrote:

>I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's >almost like it's dissipating the heat faster than I can apply it. With both a >temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally >tried. The solder will barely melt when touched to the braid opposite the >iron. > >I've applied some Kester rosin paste flux as well using my trusty Kester >60/40 lead-based rosin core solder. No joy. I'm not holding the braid against >the PCB now, I'm just trying to tin the braid and then deal with melting the >2 solders (on the PCB and the braid) together later. > >My first attempt--before I realized that I was overheating it--I melted the >dielectric insulation. > >The mesh is made from some silver-colored braid which I thought is tinned >copper but now I'm of the opinion that it's steel; it's certainly not >aluminum. There is also foil which is probably aluminum but I've trimmed that >back and it's not part of this frustrating process right now. > >What's the trick to getting this braid to take solder? I've never seen this >before. > >Thanks.
If it's like this cr*p they sell at Home Despot, it's copper clad steel core with an _aluminum_ braid shield:- http://www.cerrowire.com/files/file/49223_CERRO_CoaxialCable_6U_QUADLR.pdf That would explain the copper-like heat conduction that you're observing. I suppose you could try an aluminum flux, but can't you just unravel and gather enough of the shield to crimp into a ring terminal or something? Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
"Bob E." wrote:
> > I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's > almost like it's dissipating the heat faster than I can apply it. With both a > temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally > tried. The solder will barely melt when touched to the braid opposite the > iron. > > I've applied some Kester rosin paste flux as well using my trusty Kester > 60/40 lead-based rosin core solder. No joy. I'm not holding the braid against > the PCB now, I'm just trying to tin the braid and then deal with melting the > 2 solders (on the PCB and the braid) together later. > > My first attempt--before I realized that I was overheating it--I melted the > dielectric insulation. > > The mesh is made from some silver-colored braid which I thought is tinned > copper but now I'm of the opinion that it's steel; it's certainly not > aluminum. There is also foil which is probably aluminum but I've trimmed that > back and it's not part of this frustrating process right now. > > What's the trick to getting this braid to take solder? I've never seen this > before.
It's not made to be soldered. It's CATV cable that's made for crimp on 'F' fittings. -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.
"Bob E."

> > The mesh is made from some silver-colored braid which I thought is tinned > copper but now I'm of the opinion that it's steel; it's certainly not > aluminum.
** A magnet will pick up steel wire - but no Aluminium.
> What's the trick to getting this braid to take solder?
** Unplated steel or Aluminium wires are not solderable by ordinary means. .... Phil
On 1/18/2014 11:22 PM, Bob E. wrote:
> I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's > almost like it's dissipating the heat faster than I can apply it. With both a > temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally > tried. The solder will barely melt when touched to the braid opposite the > iron. > > I've applied some Kester rosin paste flux as well using my trusty Kester > 60/40 lead-based rosin core solder. No joy. I'm not holding the braid against > the PCB now, I'm just trying to tin the braid and then deal with melting the > 2 solders (on the PCB and the braid) together later. > > My first attempt--before I realized that I was overheating it--I melted the > dielectric insulation. > > The mesh is made from some silver-colored braid which I thought is tinned > copper but now I'm of the opinion that it's steel; it's certainly not > aluminum. There is also foil which is probably aluminum but I've trimmed that > back and it's not part of this frustrating process right now. > > What's the trick to getting this braid to take solder? I've never seen this > before. > > Thanks. >
Twist the braid into a wire and butt splice on a copper wire. Heat shrink over it.
Yes it's that crap. 

> I suppose you could try an aluminum flux, but can't you just unravel > and gather enough of the shield to crimp into a ring terminal or > something?
Yeah, that's my next move. I just couldn't believe that something couldn't be soldered. I guess REALLY agressive flux is required, as you say. When it comes to broadcast TV I try to solder every connection possible. Every crimp is one more dB lost. Thanks. Crimps in hand...
On Sat, 18 Jan 2014 20:50:34 -0800, the renowned Bob E.
<bespoke@invalid.tv> wrote:

>Yes it's that crap. > >> I suppose you could try an aluminum flux, but can't you just unravel >> and gather enough of the shield to crimp into a ring terminal or >> something? > >Yeah, that's my next move. I just couldn't believe that something couldn't be >soldered. I guess REALLY agressive flux is required, as you say. > >When it comes to broadcast TV I try to solder every connection possible. >Every crimp is one more dB lost. > >Thanks. > >Crimps in hand...
I guess there's always better stuff like this:- http://nordencommunication.com/download?file=1460-RG_6u.pdf Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
"Bob E." wrote:
> > Yes it's that crap. > > > I suppose you could try an aluminum flux, but can't you just unravel > > and gather enough of the shield to crimp into a ring terminal or > > something? > > Yeah, that's my next move. I just couldn't believe that something couldn't be > soldered. I guess REALLY agressive flux is required, as you say. > > When it comes to broadcast TV I try to solder every connection possible. > Every crimp is one more dB lost.
You must do lousy crimping, if you lose a dB. -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.
On 01/18/2014 10:50 PM, Bob E. wrote:
> Yes it's that crap. > >> I suppose you could try an aluminum flux, but can't you just unravel >> and gather enough of the shield to crimp into a ring terminal or >> something? > > Yeah, that's my next move. I just couldn't believe that something couldn't be > soldered. I guess REALLY agressive flux is required, as you say. > > When it comes to broadcast TV I try to solder every connection possible. > Every crimp is one more dB lost. > > Thanks. > > Crimps in hand... >
I would have thought every soldered joint is one more reflection.
>> When it comes to broadcast TV I try to solder every connection possible. >> Every crimp is one more dB lost.
I'm no RF expert, just my impression--possibly mistaken. Thanks.