DAVE LOWERY’S TOP TIPS

In my experience of building kits – etched brass kits in particular – you plough through the main construction with reasonable care and endeavour, ending up with something approaching 80% complete. And then there are those final small pieces that, if left off, wouldn’t really spoil the model too much. But, at the same time, you would know that you really should have taken the time and effort to finish it off properly.

Such was the case with a brass kit for the Freightliner FLA ‘low-liner’ intermodal wagon, which has a lot of in-fills to the outriggers. Two such parts which fit into the centre ends of the wagon needed to be fitted.

I made sure the part was the correct shape for the hole it would fit into, before soldering a piece of brass rod to it so I could offer it into place. Only when alignment was perfect was the part soldered properly.

Because the main body is layered, there is a lot of brass involved. Therefore, to solder the parts into place requires a lot of heat.

When the soldering iron was offered to the job, it could only produce small tacking blobs of solder, rather than flooding the joint evenly. This was purely down to the volume of brass, which was effectively sucking the heat out of the iron’s tip. Clearly, a more effective source of heat was required, which is where my Proxxon mini blow torch comes into its own. After adding flux to the surface and applying heat, those tacking blobs of solder applied with the iron are re-melted. The flux encourages the molten solder to flow freely into the joints. Furthermore, the tack-soldered bond holding the aforementioned brass rod support was also melted, allowing the rod to be removed at the same time… a good result all round!

Once all the brass work is complete and the model washed in soapy water and allowed to thoroughly dry, it is time to remove excess solder after filling any gaps. For this job, I use milling tools to fit into my power hand drill.

I used an end miller to remove solder from the ends of the brass plates, flapper wheel sanders to remove solder on flat surfaces and small ball burrs to get into awkward areas to remove surface solder.

Once the model has been thoroughly cleaned, whitemetal castings and/or 3D-printed parts can be added. More cleaning will follow, before primer is applied and we’ll be ready to start painting.

Then there are those awkward, hard to get to areas such as within these inner channels of the wagon body frame. For this, I used a small ball burr tool that cleaned the worst of the excess solder away.

Where there are plates soldered over the main body, an uneven film of solder is likely to have built up around the edges. This can be flattened using an end miller in a power drill or a flat file.

Finally, for the flat surfaces of the wagon body plating, a good old flapper abrasive wheel in the mini drill did the trick. Make sure you hold it square to the job, so the solder is removed evenly.

Over the years, I have collected plenty of metal weights from older ‘OO’ diesel locomotives. They make for excellent clamping tools, holding parts securely during soldering.

Some of the parts on this FLA wagon kit were difficult to hold in position while soldering, so I soldered a piece of brass rod to the part, which was then used to hold it in position.

The part was tack-soldered in place, and then coated in flux. Using a small blow torch, the solder will be re-melted and will flow easily into the joints, while the supporting rod will drop off. Be sure to work on a heat-resistant surface!

Cleaning up after soldering is essential for a good paint job. Always wash in water and detergent to remove traces of flux. Mechanical cleaning can follow. A variety of sanding drums, milling bits and a mini drill can do the job quickly.