I thought I would document the latest steps in my efforts to resolve the build issue with my Mallard Duke. As noted in earlier posts I have built it with both the boiler and smokebox the wrong way around. The problem manifests itself in the chimney and dome being in the wrong place. This entry is about my latest steps to resolve the problem.
The smokebox is simply a wrapper on nickel silver and white metal formers, so was relatively easy to remove and will be reattached the other way around. The boiler was a bigger problem, it could have been removed and turned, but there was a cut out for the motor which would have ended up at the wrong end. So I will have to relocate the dome, which means filling a hole in the boiler where the peg of the dome went through the boiler.
I had decided I would fill the hole with solder, but obviously the solder would just fall into the boiler, so I got a bit of scrap etch to put inside the boiler, question was how to get it there. My solution was to bend the brass to shape, drill a hole and solder in place a brass lace pin through the hole in the scrap brass. The idea was to poke the pin through the hole in the boiler I needed to fill so that I could hold the plate up against the inside of the boiler tube whilst flooding the hole from the outside with solder. The next issue was to get the plate down the boiler tube and into position. My solution to this was solder a length of brass wire to the underside of the brass plate and use the wire to manipulate the plate in the boiler tube. I used low melt solder for this joint with the intention that when I applied the heat to flood the hole with solder the brass wire would simply fall off.
With a little bit of fiddling, and bending the wire slightly I got the patch in place and proceeded to fill the hole with the highest melting point solder I had. I deliberately overfilled the hole so that I was sure when I filed it back to shape there would be no pits. Rather nicely the brass wire fell off as hoped and could be withdrawn from the boiler. I now had a mound of solder with a brass pin sticking out the top and no more hole in my boiler.
After cutting the pin off as low as I could the files came out and I spent a happy hour filing back the solder to shape, attacking it with a brass wire brush and then the dreaded fibre glass pencil until I have a smooth surface which followed the contours of the boiler.
Next I started to put the wrapper back, this time with the hole for the chimney to the rear and not the front. It is not completely soldered in place yet, but it is looking a lot better than the low point I was at yesterday.
I still need to finish attaching the smokebox wrapper, add back the footplate detailing I removed and then look at removing part of the rear boiler band and the two parts of the front boiler band before adding a complete new front boiler band. Not to forget of course fitting the dome in the correct location. However I now feel a lot more confident that I can get back to were I was, only this time with the chimney and dome correctly positioned.
I had been dreading sorting this out, but actually it was not as bad as I feared, although it would have been better if I had built it right in the first place. You live and learn, but at least it was not a fatal mistake and often more is learnt by making mistakes and correcting them.