John Fowler Diesel Mechanical 0-4-0

I am often asked how I punched the louvres.

Preamble
People have occasionally said to me “It’s OK for you, you have machine tools and know how to use them; how am I supposed to do it?” or words to that effect. Now I understand their argument but I cannot answer their question because I do not know how to do it without machine tools because that’s the only way that I know. However, I have often been impressed by the improvisations that other have made so I offer what I did hoping that, if machine tools are not an option, some improvisation can be devised.

The Louvres
There are two type of louvre; both are made from 0.010" brass shim but the larger ones on the bonnet and transmission cover were punched individually, and smaller ones on the cover to the starting engine were pressed in at one go.

Dealing with the smaller louvres first, because they were easier. I made a steel punch (right) by milling a series of saw-tooth ridges (ie like a northlight roof) on the end of a piece of bar and, using a vice, I pressed it into a generously sized piece of shim stock that was backed up with a sheet of lead flashing. Marking out from the raised ridges that represent the louvres, I cut the panel to size.

The larger louvres (example right) required a punch and a die and a some trial and error to achieve the required shape, size and spacing.

Although the bolsters that hold the punch and the die are from a small fly-press they were used only to line up punch and die as the louvres were formed by squeezing the two bolsters together with hand pressure alone; the ingenious could probably rig up something sufficient in a (machine) vice. The mild steel punch (RHS in photo below) is shaped for the inside of a single louvre and the mild steel die (LHS) is a deep hole in the shape of a very tall and thin D that is filled with rubber (cut from a pencil eraser). The larger rectangular hole, to the right of the die in the photo, is a recess for the previously formed louvres but the louvre most recently formed is pressed against the left-hand edge of this recess to ensure correct and consistent spacing. A further refinement of the die portion is the two fences that guide an accurately cut strip of shim so that the louvres are formed in line.

I also used this arrangement to punch the louvred panels on my model of a Steam Turbine Electric Locomotive.

At the time I built my model, I knew that the details of the interior of the cab in the Vulcan kit were mere conjecture.  However, from the GA drawing, I did know the profile of the control panel and the shape and positions of the rear sandboxes, the handbrake standard and the toolbox/seat, so I fitted these but left the remainder until I could inspect an extant prototype or somebody publishes some drawings or photographs.

A somewhat undignified view of the model from below.  The open frame motor drives a 2.5:1 spur gear reduction followed by a worm drive to the rear axle (to the right in the photo), which was modified and taken from a Sevenscal L&Y Pug. The jackshaft driveshaft (to the left in the photo) is made in two halves that are connected by an insulated muff within the dummy final drive housing.