Soldering iron equipment

[Marco Leavitt]

So I've decided to finally tackle the pile of dead XLR cords I have accumulated over the years by re-terminating all of them. Can anyone recommend what equipment I need to get started? Is there a point to buying the more expensive variable temperature soldering irons? I haven't held a soldering iron since middle school.

[Rick Reineke]

I prefer a multi or variable temperature soldering station, however for XLR and 1/4 connectors only, a 30W pencil/iron would work.; Other tools one would want on-hand, wire strippers, razor blades, small side-cut nippers, needle-nose and other assorted small pliers, a de-soldering tool/pump. A 'helping hands' type tool/clamp/holder and is a must-have IMO. I couldn't live w/o shrink tubing either, especially with smaller connections.

[Bruce Dempsey]

and don't forget the patience waiting for old tarnished wires to heat up lol

[Greg Miller]

I agree wholeheartedly with everything Rick said, especially the variable-temp soldering station. If buying a conventional iron, I might be inclined to go slightly higher than 30 watts, IMHO that's borderline in some cases. You need to get the connection and solder hot fast. If you heat it slowly and you're waiting 30 seconds for the solder to melt, you have a good chance of damaging some insulation.

If you don't want to invest in a de-soldering station, one of the fluxed wick products (names like Solder-Wick) will be adequate.

And if you do start using heat shrink, you should have a heat gun at well. Doing it with flame is not really civilized.

[Marco Leavitt]

Thanks everyone. Are brand names important to any of this? Is there anything I should avoid when putting all this together?

[Rick Reineke]

Generally, 'you get what you pay for'. Weller, ect. But like audio gear, experience & skills have a lot to do with it. I can't count how many times I've forgotten to put the connector barrel, insulator and heat shrink on prior to soldering the connections.

Yes indeed Greg, a heat gun would definably be wanted. I've previously toasted my share of connections and cable with a matches, lighters and stoves. A lower cost heat gun should surface in this job though.
FWIW, Harbor Freight tools frequently has coupons for a dual temp. heat gun for around $10.

[Greg Miller]

Originally Posted by Rick Reineke

I can't count how many times I've forgotten to put the connector barrel, insulator and heat shrink on prior to soldering the connections.

Yeah, that's especially fun if you've just finished soldering a PL-256 RF connector. :-(

[Seth Bloombaum]

I like the Paladin solder pump for removing the old stuff. Solder wick is handy too, but I use the Paladin a LOT.

A cheap "helping hands" with a couple of alligator clips for positioning leads.

A few years ago I came across a used panovise, great for positioning connectors, but expensive when new.

Reading glasses. Good light.

A small fan you already have to blow the fumes away from the work (and you).

GOOD solder.

If you get an iron instead of a station, be sure to buy some of the sponge material (that comes on a station). You get it wet, wring it out, and it can really clean off that iron.

I used to use a small file to dress the soldering tip smoothly, but modern tips don't pit the way they used to.

SMALL diagonal cutters, needlenose pliers, and hemostats. Medium diagonal cutters. A good wire stripper, though with practice you can use the cutters. These good hand tools really make a difference.

A "spudger", a little tool that just pushes wires around, hot or not.

An assortment of GOOD shrink wrap, in clear and black.

A labeler.

A cheap heat gun.

Always tin leads before soldering. Always start with a clean iron, then a glob of fresh solder on it to conduct the heat from the iron to the work.

I use all this stuff and more - with the exception of the panovise and solder pump, the latest cheap imports at harbor freight actually work quite well.

Solder and shrink better come from the electronics store...

[Richard Crowley]

An excelent three-part video series from David Jones on soldering:
EEVblog #180 - Soldering Tutorial Part 1 - Tools

EEVblog #180 - Soldering Tutorial Part 1 - Tools - YouTube

EEVblog #183 - Soldering Tutorial Part 2

EEVblog #183 - Soldering Tutorial Part 2 - YouTube

EEVblog #186 - Soldering Tutorial Part 3 - Surface Mount

EEVblog #186 - Soldering Tutorial Part 3 - Surface Mount - YouTube

[Rick Reineke]

Another item I forgot to mention.. Seth is absolutely correct in recommending a 'small file set'. for rounding off sharp edges the can poke through isolators and shrink tubing.. and cause a short... and naturally this would occur at the worst possible moment.

[Bruce Dempsey]

what do you fellas think of the gas jobbies strictly for joining twisted copper wire?
I have both a 40w iron and a 100/140w gun and find the heat time too long as a rule but maybe is dirt on the wires or something.
Another question if I may and apologies to the OP for butting in his thread: What if the wire is tarnished, do you dip it in a bit of soldering paste first?
tks

[Greg Miller]

I don't file the tips if I can possibly avoid it. Some tips are plated and once you get through the plating down to the base metal, then the tip will corrode and pit.

Not sure what Mr. Dempsey means by "gas jobbies." Hopefully he does not mean a propane torch ... that's for plumbing, and much too hot for wiring.

Start with a clean tip, turn on the heat, put a dab of fresh solder on the tip. After the solder melts, put the tip w/ solder against the wires, and the solder will conduct the heat to the wires. Press some more fresh solder against the wires, it should melt within a few seconds ... certainly less than 30 seconds with 100 watts. (Mr. Bloombaum has also described this, above. Pre-tinning the leads is also often helpful.)

Electronic solder contains a flux core, so you should not need more. Don't use "solder paste," that is acid-based, again for plumbing work. It will ultimately corrode the wires and ruin the connection. Only with very old and corroded wires will you benefit from additional flux. If you do feel the need, be sure you get a good liquid flux in a bottle, and brush it on sparingly. If you end up with a big surplus of flux when the joint is finished, it's better to clean it off (different flux needs different solvent).

[Seth Bloombaum]

Originally Posted by Bruce Dempsey

what do you fellas think of the gas jobbies strictly for joining twisted copper wire?
I have both a 40w iron and a 100/140w gun and find the heat time too long as a rule but maybe is dirt on the wires or something.
Another question if I may and apologies to the OP for butting in his thread: What if the wire is tarnished, do you dip it in a bit of soldering paste first?
tks

If the wire is tarnished, I'd cut off all the exposed copper and start over, stripping insulation to expose fresh copper. If that's tarnished too, throw it away and get new wire!

"Gas jobbies"... an iron that runs off a little teeny propane cylinder, the whole thing about the size of a carrot? A friend had one, they get darn hot. Too hot for typical signal connectors.

Gotta' ask, what are you soldering that a gun won't melt solder in a couple seconds? If you're doing 12ga. wire and bigger, for power supply, then you will need more wattage. But those connectors are typically screw or crimp, not solder.

For common signal applications, we're talking 20 to 24ga, and your gun ought to work fine or maybe be too hot at the 100w setting. If it doesn't, you do need to look at your technique, as several have mentioned. Tin, clean the tip, use a glob of solder to transfer heat from the tip to the work (this is very important).

I'm a little out of my depth with wattage for an iron; it used to be common, but now electronics irons or iron tips are rated in degrees. I suppose you could have big watts at low heat. 700 and 750 are common temps, sometimes 800 for big connectors. A small tip for small work, a big tip for big work - this relates to how much heating capacity the tip has.

The problem with heating wire or a connector for 20 seconds or more is that in that time the heat will be conducted to the insulation or the plastic structure of a plug/jack, and yes, the material will melt. It's a fine balance of time and temperature. Somebody mentioned melting insulation above, this is a real problem with bad technique or equipment.

I can't believe none of us have mentioned creating a mechanical connection! That means, you don't want the solder joint to be stressed in use, by plugging and unplugging for example. Maybe it's in the youtube videos above, I haven't looked at them. With Neutrik-style XLR connectors, or when you're wiring within a chassis, you've got strain relief. But for other connectors and some chassis joints you need to bend the wire around the terminal before soldering for a good, long-term joint. It doesn't take much, just tin, then form a U in the end of the wire (tiny U), hook the U on the connector, and crimp it together with the needlenose pliers. Then solder.

[Seth Bloombaum]

Originally Posted by Richard Crowley

An excelent three-part video series from David Jones on soldering:
EEVblog #180 - Soldering Tutorial Part 1 - Tools... Part 2... Part 3

Ack, an hour and 44 minutes on soldering with a perky aussie! Probably excellent, but I couldn't get past the fifth minute.

Perhaps there's an excellent 10 minute tutorial out there on the basics for audio connectors?

Speaking of the basics, what do you do when you're trying to figure out how to wire a 1/4" tip-ring-sleeve (aka stereo phone) connector to an XLR-male? I always go to this Rane Technical Note #110. At the bottom there's a link to download it as a pdf. There are some differing opinions about grounding out there, but Rane's approach is respected, too, and the connector wiring diagrams at the bottom are very solid.

PS. I misnamed the handy Panavise above in the thread. Panavise, not panovise. The 301 is not really that expensive at your favorite online retailer. You don't need a vacuum base for soldering audio connectors...

[Mark Watson]

Originally Posted by Marco Leavitt

So I've decided to finally tackle the pile of dead XLR cords I have accumulated over the years by re-terminating all of them. Can anyone recommend what equipment I need to get started? Is there a point to buying the more expensive variable temperature soldering irons? I haven't held a soldering iron since middle school.

If money were no object, I prefer Snap-On brand, especially for the side-cutters and files. They have a cordless (butane) soldering tool which can also perform the heat-shrinking task. Will only set you back $185.00. Good quality side-cutters really make a difference though.

Mark