I realise that there has been a 'bit' of a gap in posting progress on this jobbie. Might I plead too busy building the thing for Telford and documenting it into the instructions? Progress has been rapid and I will cover the ground here at a fast trot; a phrase acquired from the Present Mrs and Miss T who in return are able to use the word backhead.
First the footplate. Well, it goes together easily as you would expect. Not shown is the wooden buck that I make for each loco that I build to support the footplate; it was a technique used by Guy Williams.
So the next main job is the firebox. This consists of some thick plates that form the front and rear and an etch that forms the outer skin of the firebox. Martin suggest using some spacers such as the ones he used. Not having Martin's spacers I tried several techniques such as two lengths of 4mm studding and a load of nuts to space and lock (wouldn't stay square when touched) and then turned up some spacers from some rod in the spare metal box. The set up is shown below.
This method is under review as we would like to come up with an easier method. The large diameter of the lower spacer was taken care of by using a couple of parallel slips to raise it off the surface that I trued the assembly from; I have a small surface plate but a lathe bed, piece of glass or even a new flat piece of tufnell will do to provide a flat, level surface to set the ends flat, true and parallel.
Now, progress in the form of the skin on and the inside of the front edge of the firebox filled with plumbers solder to build up the inside of the front edge of the firebox.
To get the front formed correctly, work down in the size and fierceness of the cutting/polishing tools and keep moving the firebox around so that you see the work from all angles and above all, have a couple of clear photos of the real thing in front of you - the top corner has a big radius. Other than that, everything else in the photo is routine.
Finally, for today, forming the boiler. Mine was already partially rolled however, I did do some work to try to get the curve to continue to the ends. The set up for soldering is as shown below. The joining piece and the inside of the boiler were tinned and then assembled into the following set up. Then it was in with the iron set to v hot and hold things down with an old lolly stick. Here is my set up; if you don't have V blocks I'm sure a couple of books or some scrap wood with some V's cut in would do the job.
The brilliant thing about Martin's design is that when you put the end formers into the cone it goes to the correct shape and becomes rigid. So, finally for now, here is the coned part of the boiler looking bright and shiney.
Those who were at Telford might have seen the finished model in grey primer, so there is more to repot. Luckily a 4000 gallon tender has been found and I am well on with that build and photography. I'll try to catch up here - honest!
Simon