THESE PHOTOS SHOW MODIFICATIONS which I built into a 4-wheel bogie for my LNER Reid Atlantic 4-4-2. However, and to my regret, they were taken at final assembly and the matt black paint hinders good visualisation. In retrospect I should have left all ‘hard to see’ locations unpainted.

1. The bogie with is new slotted space ready for fitting. Note the close sliding fit of the washer at bottom of spring – the brass tube slides through but not the spring. See the slotting of the hole in the bogie stretcher – only 1mm each side initially – widen if necessary for bogie side play.

2. This shows the bogie slotted plate in position, retained by 10BA screws to what I call the ‘window’ plate.

3. View of the ‘window’ plate with removal of the bogie plate. Observe the ‘window’ cut giving access to the front 6BA chassis/footplate screwhead; two 10BA nuts have been soldered on the upper surface of the plate (or spreader or spacer) which rests on the upper edges of the two support plates already soldered to the inside of main frames (and located with the scratched markings).

4. The window plated from above, you may just see the two 10BA nuts. In this prototype I replaced the front chassis space with a narrow piece, drilled 6BA for chassis/ footplate fixing (but read on!). These two narrow spacers were intended to be ‘temporary’ should removal of original front spacer be needed for access to the top side of the window piece; I do not think, in retrospect that was necessary. But read on! As described later, any front chassis spreader, especially if it carried the 6BA footplate screw would be built normally, as access to 6BA screw is via the ‘window’ cut out. This window plate with the two 10BA nuts on upper surface can be introduced from below and temporarily held against the top of the two support plates during soldering. The bogie 8BA screwhead rests in the window. The initial length of the thread on the 8BA screw is from chassis mid point to rail – shorten as needed.

So to recap, the ‘window’ cut out has two purposes, one access to 6BA footplate screw, and clearance for the 8BA bogie screwhead. Remember to scribe on all parts the position, vertically, of the 8BA bogie screw. Scribe where relevant the vertical line of the long 8BA bogie screw. This helps the lining up and positioning of all parts. So scribe it on the inside face of mainframes and ‘window’ spacer, bogie top spacer and the two support plates for the window spacer. Consider pop marking holes.

Check positions (8BA x2, and 10BAx2) before drilling the 10BA holes. Align bogie top bar and tack solder to window plate and drill pilot holes through both. Then desolder, clean surface, open up 10BA holes, solder the two 10BA nuts to upper surface of window plate (hold nut in place with 10BA screw), apply oil to the screw thread on both sides of screw and carefully solder quickly; but if you are not happy with the take of the solder, allow to cool, loosen screw, dab on fresh oil and tighten screw and apply more solder – and that’s it.