Soldering iron for automotive use

[RobertGary1]

After years of struggle with my HF 30 watt solder iron I'm thinking I should look into something a bit better. I feel like the HF irons I've bought only give good heat the first couple of usages and then go cold (even touching the solder to the iron no longer gives an instant melt). I've heard Weller are good irons. Any opinions on this model...

BTW: The biggest challenge in automotive soldering is that you usually don't have a solid surface to support the wire. It would be awesome if someone made a hot tip that would clamp over the wire and could be released with a cold handle. When working under the hood the wire tends to move away as you place the iron on it.


http://www.ebay.com/itm/Weller-SPG40...item2c6b07b9b1

-Robert

[mattwithcats]

Had one of these for years, takes a minute to get hot, but works great for minor projects.

30 watts, not to hot or cold.

Hint - get a spare tip.

http://www.radioshack.com/product/index.jsp?productId=2062758&filterName=Type&filter Value=Soldering+irons

[OldNuc]

Quit piddling around with these low temperature, solid state device irons. They are not up to the job. Use the correct tool for the wiring you are dealing with under the various environmental conditions encountered.
http://www.amazon.com/Weller-D550PK-...=soldering+gun
These work just fine.

Get a smaller version of these pads so you have a backup for the wiring to be soldered. http://www.amazon.com/ASBESTOS-FREE-...=soldering+pad

[fdryer]

True field work without a cord.

http://www.staples.com/office/suppli...nalize=certona

http://www.parts-express.com/pe/show...=%7Bkeyword%7D

http://www.iso-tip.com/products-page/

[RobertGary1]

Is this a good poor man's alternative or not worth it??

http://www.harborfreight.com/welding...-gun-4328.html

-Robert

[lamping.ap]

Originally Posted by RobertGary1

Is this a good poor man's alternative or not worth it??

http://www.harborfreight.com/welding...-gun-4328.html

-Robert

Works fine for me. Depends how often you plan on using it I suppose.

[fdryer]

Only if you need it for one time use.................. I regard soldering irons as an extension of my (meager) skills and there's no room for cheap irons. My first iron is a (standard) Weller 25W and used to make one tv and stereo receiver - both Heath Kits. You may remember the company from years ago. Its still in pristine condition and the tip has never been replaced. If the price is right and you want a plug in, go with Weller. Stay away from unknown brands if you're interested in reliability.

When I was in field work I was carrying around a standard plug-in 25 watt soldering iron until I saw other field techs pack the new (back then) portable butane soldering irons. Small, compact, no wires, and the only additions needed were a butane can for refilling and a butane lighter. It made for true field work anywhere without needing an a/c outlet. I shopped until I came across Radio Shack's version for about $20-$30(?) It uses the old flint wheel spark generator and hardly worked (for me) so I always carried a butane lighter. This inexpensive butane powered soldering iron lasts about 30-minutes on low (25W/30W) and less if used on high power (100watts?) There are replaceable tips and I settled on the narrow one but a general purpose tip is ideal for anything outside the house. No more searching for an extension cord to extend the range of an electric iron and most butane irons are adjustable to allow for winds when low setting cools off the tip.

I went for the least expensive as others are more costly with more features and attachments. For the price, it was ideal for me and still used on occasion - definitely used if I have to solder anything in the car. The catalytic element means no flame and dialing in the amount of heat is right there at your finger tips when needed.

[OldNuc]

Buy the big Weller gun, you will not need another. The 25-50w irons do not have the BTU output or tip temperature to correctly solder #14 wire. I have seen one of those little butane torches light up a Honda real well, the customer was not impressed. Neither was the boss. Flame under the hood can get you in trouble rapidly.

[fdryer]

As I stated, no flame. I can't vouch for incompetence.......................

[mattwithcats]

Hate those cordless soldering irons, way too hot or out of fuel...

Radio Shack was ten clams, came with stand and solder...

Use a telephone splice on minor wires, solder only big or mission critical ones...headlights or brake lights...

m.radioshack.com/radioshack/product/detail.do?itemId=2062793&op=%22http://www.radioshack.com/product/index.jsp?productId=2062793%22

[fdryer]

Well, how long does it take to solder one joint? 5-10 seconds? One whole minute? Using a butane iron on high setting? Unless you're familiar with soldering and how little heat and time it takes to solder, you're uninformed or not familiar with correct soldering technique. 'Wetting' is the key to soldering.

I'll even confess; I've been soldering the wrong way for many years but have never burned/cooked/ruined any soldering joints. While I'm not proud of it I recently learned the correct way from trained, licensed airframe and power plant experts (now termed aviation technicians) that informed me of my incorrect ways. My wrong technique kept me from simple soldering mistakes many make from unfamiliarity with soldering. Everything I did/do still works to create a near perfect solder joint. And I work on circuit boards when necessary where mistakes are ridiculed by fellow co-workers!?

[RobertGary1]

Originally Posted by fdryer

Well, how long does it take to solder one joint? 5-10 seconds? One whole minute? Using a butane iron on high setting? Unless you're familiar with soldering and how little heat and time it takes to solder, you're uninformed or not familiar with correct soldering technique. 'Wetting' is the key to soldering.

Can you elaborate on 'wetting' (I assume its more than pre-tinning). Most of the solder I've done have been on aircraft (typically only done for avionics, I believe its prohibited to solder power carrying wires in Aircraft).


BTW: Aviation mechanics are referred to as "A&Ps" because they are licensed to work on airframes separately than powerplants. However 99% hold both so are called "A&Ps", however, I don't believe the FAA has ever used that terminology.

-Robert

[td1238]

http://www.ebay.com/sch/i.html?_trks...at=0&_from=R40

These work as well as the 120V versions, but if you get one with a cigar lighter plug, and it has the thin cord, replace it with a standard lamp cord of the same length. The thin cord will not carry enough current, and the iron won't get hot enough.

Ideally a Weller is far superior, though, especially when working on a car in the cold. However, for small work, I really like being able to solder in my car without having to run an extension cord.

[OldNuc]

Get one of those with a high enough wattage to do the job properly and plug it into the cigarette lighter and you will be able to move onto F-5 repair right after finishing the soldering job.

[OldNuc]

Originally Posted by RobertGary1

Can you elaborate on 'wetting' (I assume its more than pre-tinning). Most of the solder I've done have been on aircraft (typically only done for avionics, I believe its prohibited to solder power carrying wires in Aircraft).


BTW: Aviation mechanics are referred to as "A&Ps" because they are licensed to work on airframes separately than powerplants. However 99% hold both so are called "A&Ps", however, I don't believe the FAA has ever used that terminology.

-Robert

Electrical wiring and circuit components are to be done with a rosin type of flux. The purpose of the flux is to protect and clean the coper so wetting can occur. This means adequate BTU capacity and tip temperature. http://www.circuitrework.com/guides/7-1-1.shtml You can tell by looking. In automotive work and other larger gauge wiring the problem is not enough BTU capacity in the tip/heating element and temperature. The idea is to get the solder joint made before heating up 20 foot of wire due to low tip thermal capacity. Those 25-40wattt irons are for circuit board work only. There are higher wattage irons but they suffer from a low heat transfer rate due to the length and size of the tip. Power wiring is crimped with gas tight crimp sleeves as solder will wick back into the cable and that markedly increases the probability of a vibration induced cable/connection failure.

[RobertGary1]

I feel like 30 watt irons used to be enough. How about the theory that the new lead free solders require more heat and that (especially in automotive applications where solid contact with the wire is more difficult in confined places) higher wattage is needed.

-Robert

[madpogue]

I have one of those big Weller guns that's so old, I've forgotten where I got it. I think the case is bakelite; a bit of it is broken off. Still blows away any 30W-range iron I've used. Even the little tungsten bulb that lights up the work when you hit the trigger, that today's kids would laugh at, still works.

And indeed, something that would automagically hold both wires (or wire and terminal/board/whatever) while you futz with iron and solder would be the next sliced bread invention.

[OldNuc]

The skill comes in when you hold each wire in proper position and also hold the solder and the gun, then get them all together at the same time.

The Weller gun is not for solid state circuit board work either, right tool for the job issue. Weller makes a temperature controlled soldering station that works well on circuit boards and surface mount components.

The 260/200 watt gun has 2 headlights.

[PlasticCarsRock]

I prefer a small 15/30 watt iron for most things. It's far more maneuverable than the larger "gun", and just easier to work with in general. It works fine on 16 gauge (as long as it's just two wire, not three), but anything heavier is too much for it. I almost always leave it on 30 watts, unless I'm doing computer circuit boards or something (which is pretty rare).

I do have a Weller gun very similar to the one OldNuc recommends, which I use for larger wires or if I'm just doing something quick.

With the 30 watt iron, you need to let it warm up for a minute or so before you can use it (don't rush it). The powerful "gun" heats up in a matter of seconds, so it's a better choice if you're just connecting one or two wires, but in almost all cases, I find myself reaching for the small one.

It really depends on your needs and personal preference. If you're just getting one for occasional use, the powerful one is probably a better choice, because you cannot do large wires with the small one, but most wiring in cars is pretty small.

With either iron, make sure the tips are clean and tight (a loose tip won't heat up well).

Also, if you get a small one, get a decent one (it doesn't have to be expensive, but I would stay away from harbor freight and stuff with no brand). I have used several cheap (no brand) ones that were supposedly 30 watts, but never heated up much at all. I'm very happy with my radio shack one (~$15-$20, I think). I solder enough that I wouldn't mind spending more money for something good, but it does everything I need.

Originally Posted by OldNuc

The skill comes in when you hold each wire in proper position and also hold the solder and the gun, then get them all together at the same time.

That can, indeed, be quite difficult. I find it's a lot easier with a small light iron. To hold the wires, I have a piece of coat-hanger wire bent in a U-shape with an alligator clip on both ends. I can bend it to whatever size/shape I need, but it's strong enough to hold the wires exactly as I set it. (If you don't have coat-hanger wire, you can also use thick single strand copper wire as is used in household wiring.)

[ssicarman]

Soldering wiring you want a gun that can give you good high fast heat. Piddling about with low watt solding guns is a waster of time and money. They are for circuit board work.
I have the Weller D550PK at work. Used to have the 140/100 amp for work, not enough heat for larger wires.