Brian Madge Alice class Hunslet part 4 - cylinders and slidebars.

The slidebars are machined from nickel silver and are ready formed, which makes assembly easy as the hard work has already been done. A screw needs to be soldered in place to bolt the assembly to the frames, 16BA is provided but I found this to be a sloppy fit in the machined hole in the slidebar so I used 14BA instead, opening out the frame holes slightly with a 5 sided broach. Also 14BA is a lot less fiddly than 16BA! Then the turned brass cylinder can the soldered in place;

 

188 degree solder was used for the screw and cylinder.

Cylinder wrappers are half etched with a raised section on one end. This raised part is designed to poke up through a cut-out in the footplate and represent the top of the cylinder casting, which on the prototype can be seen sitting above the footplate either side of the smokebox. Although I can see why Brian has designed the wrapper this way, to make the entire cylinder including the top part in one piece, its a bit of a faff trying to not only line up the wrapper so that the top sits nicely in the footplate cut-out but also to form the wrapper so that the upper part can sit at an angle. So I've ignored the raised section and wrapped the overlays right round the cylinders;

 

Wrappers soldered in place with 145 degree solder.

I'll make up the cylinder tops later on with scraps of plasticard filed to fit into the footplate cut-outs.

Before fitting the cylinder/slidebar assemblies I had to cut down the 14BA screws. However, before I snipped the screws to length I fitted two nuts onto the threads, screwed down to the slidebars.Then the uncovered part of the thread was filed away until a nut would slide along it. The screws were then cut down leaving part of this filed section attached. The reason for this is simple - it can be rather fiddly trying to get a small nut to start on the end of a thread, even more so when that thread is difficult to get at i.e. between two frames. By doing the above the nut can be placed on the filed section where it will sit without falling off until you are ready to start screwing the nut down the thread. Hopefully this sketch will makes things clearer (click on the pic. for a larger image);

One assembly in place;

There are etched cylinder end covers still to be added, I'll epoxy these in place later on (when I've got some Araldite mixed up for another job).

Crossheads and connecting rods next.

Paul.