[fyleow]

I hope this isn't a silly question but here goes.

I've done a fair bit of soldering work on circuit boards but not interconnects and I'm going to do my first one tomorrow which is a headphone cable for my HD600s.

I ordered the Cardas Sennheiser connectors and they came with some flux paste. Reading some of the posts here the recommendation is to put flux on the wire and the connector before soldering. Can someone please explain to me why that's needed? I know there's some flux that's in the solder already and when soldering components I've never had to add extra.

When do you use the flux and in what quantity? Do you apply it first on the wire/connector then tin it with solder?

Another thing I was wondering about is the amount of wire exposed for soldering to the connectors. I've heard the shorter the better but how short is short? 1 cm? 1 mm?

 

[rembrant]

Flux helps clean mild corrosion and aids in the flowing of the solder. I personally don't use much of it but some people do. If you are new to soldering or are working with small components it is helpful. For wire and connectors I usually tin the wire with tip cleaner and tinner which does contain flux. Also, it has been my experience that gold connectors solder much easier than nickel.

Be sure that you make a mechanical connection and not just a solder one. Trust me. Once you get your materials together it will become more clear.

 

[qusp]

expose/strip about 3-4mm of wire, tin the wire, but not the cardas connector, as it doesnt have too much space in the hole, put flux on both parts. put the wire in the hole, with about 1-2mm of bare wire protruding out, put the iron on the wire and feed solder onto the wire until it starts to bead, then tip the connector and wire downward and shift the iron to the cardas connector, push the wire in about 1mm (a little bit, you still want a touch exposed; and finish the joint quickly. flux is important for this job (i use it for almost everything actually) as rhodium heats up VERY QUICKLY and the plastic part will soften and melt easily if you are not uber quick. flux aids in forming a good connection swiftly

 

[fyleow]

Quote:

Originally Posted by qusp /img/forum/go_quote.gif expose/strip about 3-4mm of wire, tin the wire, but not the cardas connector, as it doesnt have too much space in the hole, put flux on both parts. put the wire in the hole, with about 1-2mm of bare wire protruding out, put the iron on the wire and feed solder onto the wire until it starts to bead, then tip the connector and wire downward and shift the iron to the cardas connector, push the wire in about 1mm (a little bit, you still want a touch exposed; and finish the joint quickly. flux is important for this job (i use it for almost everything actually) as rhodium heats up VERY QUICKLY and the plastic part will soften and melt easily if you are not uber quick. flux aids in forming a good connection swiftly

Thanks...I will try this method once I get a new pair of the Cardas connectors in. I thought I was good to go after testing it with the multimeter but after I epoxied and heat shrinked everything the audio started to cut out if I moved the headphone cable at the headphone end in certain positions. I don't think the Cardas connectors are salvageable at this point.

What sort of temperatures should I be using? I think I've been using too high (600F). And what's a good way to test the joint? Mine checked out fine with the multi meter and didn't have issues until later.

 

[Budley007]

Sounds like you had a cold joint. Cold joints will, a lot of times, pop loose with some flexing and pulling. Look for cloudy or gray dull solder around the connection. A good joint has a mirror-like finish throughout and is tougher than most people initially assume.