Friday, October 04, 2013

Soldering irons for wagon building

Dan asks: What soldering irons do I need for brass wagons I would like to solder up and start the art of soldering. I have read your Parkers guide but got a bit lost to which one I need I have the Antex CS18 18w iron, but I know that it is no good for soldering up the wagons.

Hmmm. I'd disagree with the idea that an 18w Antex iron is no good for etched wagon building. I'm assuming you are working in 4mm scale so for smaller kits, it ought be man enough for the job but probably only just.

When you heat solder on an etched kit, the brass will suck heat from the soldering iron bit. If the heat is absorbed faster than the iron can generate it, the solder doesn't heat up properly. You might be able to splodge it on as though it were a paste but that's not soldering, the metal should run like a liquid. The bigger the bit of metal you are soldering, the faster it will absorb the heat.

I'd suggest a 25w iron as a minimum, but of you really want to get into this, my preferred tool is an Antex TCS230 50w. Buying one of these about 10 years ago was the best move I ever made as far as soldering was concerned. Yes, it's a bit more expensive than smaller irons, but the heat it pumps out is sufficient to allow me to work with big bits of brass including O gauge kits. Despite this, I can also use it to wire layouts up.

I'll admit a preference for Antex tools, there are a couple of reasons for this.

First, the heating element is inside the bit. This is more efficient than the element being wrapped around the bit as all the heat has to pass through the thing you want to get hot.

Second, in my formative modelling years, one of the modellers who influenced me (Dave Elbourne) worked for British Telecom. Their technical staff did a lot of soldering and were all issued with Antex irons. In BT abuse, the tools worked for great long periods of time and kept working. I like things that do that, hence my preference for the yellow handled tools. So far, I've not been proved wrong.

This is all good for electric but sometimes you need even more heat. This is where a gas powered torch comes in. Blasting solder with a small flame will heat it up faster than the surrounding metal can pull heat away so you will get the stuff to melt. Blowing solder along joins is great fun but you need to be careful the metal isn't very thin or it can expand and buckle. This is rarely a problem and if it is, I'll switch to using glue.

On top of this, you need solder, preferably tin/lead mix and some flux. I get mine (Copolux) from the plumbing isle of a DIY store. If you can't find it, Powerflow works too, it's just more vicious and really must be cleaned off after every soldering session.

I'd also recommend a ceramic soldering board from Cousins. Perfectly flat and heatproof, it's a great surface to work on.

Finally, get some wooden chip forks and lolly sticks to help hold parts. You want the metal to heat up and not your fingers!


Paul B. said...

Another couple of reasons for using Antex irons - spares are easily obtained from a number of sources, and they're nice and light compared to other irons.
Personally I use a XS25 (25w) for 4mm work.

Daniel said...

thank you very much just what I need I think I order up an xs25 (25m) as soon as poss and start work thank again Dan