How to build your first etched brass kit

Many modellers consider those proficient at building brass kits as modelling experts. This isn't really the case because etched kit assembly is similar to putting cardboard models together - the big difference is that the glue is solder and you apply it hot.

There are techniques to learn and practice will help, but unlike a card kit, you can always re-melt your solder, clean it off and try again.

Don’t pick an expensive locomotive kit for your first attempt. You might aspire to build an LNER Garratt or Fell Diesel, but these are models to work your way up to. A garden shed on the other hand, how tough can that be? Plus, you can add foliage over areas you aren't happy with – not a trick you can use on a locomotive.

Roxey's kit is an ideal beginner’s model. You do all the basic etched kit jobs – releasing parts from a fret, folding them, aligning parts using tabs and slots and then soldering. There are some etched kits designed for glue assembly, but this isn't one of them. Soldering is easier and quicker for this model. Here we show you how.

1

All parts are attached to the brass fret with little tabs. These can be cut through with a sharp knife. Once free, file along the length of each side to clean remaining tabs.

2

Turning a flat kit into a 3D object requires parts to be bent. The designer will have half-etched lines through the metal to assist the modeller. Fold the brass with the line inside the bend. Support it along the bend using flat pliers to ensure the bend is along the line you want, not along the plank lines also half-etched on the outside of the model.

3

Pliers are the simplest and cheapest aid to bending brass. If you plan to build many etched kits, a Hold'n'Fold tool is a worthwhile investment because the different-sized tongues make forming even tiny parts easy.

4

The first soldered joint is called a tack. It's nothing more than a blob of solder to hold parts together to check their alignment is OK. Make sure the metal is clean, slap on some flux, then carry a blob of solder to the joint on the tip of the iron. We'd normally do this inside the joint, but sometimes making the tack on the outside is easier because you can see what you are up to. If the parts aren't aligned, heat the solder and try again. Remember, this is only a temporary joint. It doesn't need to be pretty.

5

With everything where it should be, put flux inside the corner and bring a small amount of solder to the joint. This is the final joint, so take time to make it neat. Don't worry, if it goes wrong, just clean away the worst of the solder and try again.

6

Now it's time to clean the tack joint. Scraping or filing can be a start, but it's easy to scratch the metal surface so we’d recommend using a fibreglass pencil to wear away the solder. This takes a little while, but you'll be surprised how neat the results are.

7

The window sill is held in place by a couple of tabs pushed through slots in the wall. Blobs of solder on these inside the building are enough to hold it in place. There's no need to solder all the way because it isn't structural.

8

To hold the door frame in place, use a couple of hair clips. I could tack it in, but the clips are enough to keep it there while solder is run around the inside of the metal – another joint that doesn't need to be pretty.

9

Bend the roof so that it’s a really good fit above the shed, then fit it to the barge-boards. Joints like these are best made with a little solder. If the parts stay attached then you've used enough. Note the lolly stick under the finger to protect it from the heat!

10

To laminate two parts such as the door framing, in the back of the framing. Tinning is coating the metal with a thin layer of solder. Clean metal, plenty of flux and a minuscule amount of solder goes a long way.

11

Give the door face a polish with the fibre pen, then smear with flux. Fold the tinned framing over, push it down with a little wood and heat the solder-free back of the framing. The solder should bubble at the edges indicating it's melted. Remove the iron but keep the pressure on the framing while it cools. If this doesn't work the first time, add more flux and heat it up again.

12

According to the instructions, the hinges can be made to work, but we’re folding them at 90 degrees and attaching them to the sides with less than elegant blobs of solder. The door when open hides the blobs.

13

Flux is mildly acidic and if left on the model will turn into a greasy green slime that resists paint. The last job is a trip to the sink for a clean, any degreasing cleaner will probably work. Finish with lots of rinsing with clean water. The brass will need a spray of car primer before being painted with either enamels or acrylics.

Essential Tools for Soldering

Soldering Iron: For structural soldering, you need at least a 25W and there are lots of suitable tools on offer. For this model, we used the standard 3mm-wide bit, but smaller tips are available for fiddlier work. These slip over the end of the heating element. The other essential in this picture is the soldering iron stand. As well as giving you somewhere to put the iron when you're not holding it, the damp sponge in the base keeps the bit clean as long as you remember to wipe it regularly while working.

1. Solder: We’re using a normal cored electric solder, a 60:40 tin/lead mix. There lots of different temperature solders available and they all have their uses, but this is fine for your first kit. Lead-free solder is also available, but you need a high silver content for it to flow properly so the price tends to be high.

2: Flux: Without getting into the chemistry, flux lubricates the soldering process by improving the flow of the solder. Yet again, there are lots of different types of flux but for most work I tend to use a general-purpose paste type and plenty of it.

3: A cheap paintbrush: To apply flux to the joint. Don't use anything good as once you've used it for flux, you can't clean it up for paint.

4: Fibreglass pencil: For cleaning the metal before soldering and removing excess solder. The bristles will fill up with flux so don’t use the same tool for locomotive wheel cleaning, get another for that. Fatter fibreglass sticks are also available for the same job.

5: Ceramic plate: While not essential, a heat resistant flat surface is important. For years I used bits of wood and while they work, the surface gets burnt, soaks up flux and generally becomes a bit unpleasant. This plate came from a jewellery supplier but many model railway tool sellers stock them too.

6: Flat-faced pliers: For bending metal along half-etched fold lines. Those with serrated faces for grip can damage the thin metal.

What's the difference between electrical and structural soldering?

In a word, technique. With electrical soldering, you heat up the joint and apply the solder. That's why the solder has a flux core, it makes the solder flow. We need more solder for a structural joint so have to carry it on the tip of the soldering iron. While doing this, the flux in the cored solder will boil away, hence we need to add flux to the joint and bring the molten metal to it.

As you can see, it's amazing how you can transform an etched brass kit into an impressive, unique building. For even more kit building articles, of various levels of difficulty, click here.

Want some houses to go with your shed? Our guide on how to build and detail a card kit is worth a read. Or if you’re interested in building some roads and pavements, our handy guide is filled with tips and advice to help you model your scene.