Hornby replacement 4 hole 14mm disc wheels R8234 are of the correct pattern.
If you wish to fit the Hornby wheels or wheels with a longer axle i.e. Alan Gibson or Markits, then the following procedure should be used.
Before starting to assemble the bogie drill through the axle boxes from the inside of the bogie frame with a drill bit to suit plain capless bearings of your choice. Then insert the bearings from the inside of the side frame. Now assemble the bogie around the wheels. When the bogies are fully set adjust the bearings from the outside of the bogie onto the ends of the axles so the wheels are in line and run smoothly. Set the bearings with a small drop of Super Glue from the outside then fit the axle box covers.
For use with P4 or EM standards then the bogie will need to be widened by inserting a strip of plasticard between the stretcher plates in addition to the above procedure.
Lubricate the axle box bearings with a small amount of none mineral grease or oil.
Wheels
The Underframe.
Remove the existing pivot from the underframe and elongate the hole.
Fit two half pivot plates and a pivot post as shown.
The Bogie
Working on a flat surface glue two half Stretcher Plates together. When the glue is set and the Stretcher Plate is flat glue the Side Frames onto the Stretcher Plate.
Glue two Stretcher bars between the Side Frames and inside the locating tabs on the inner face of the Side Frames.
Glue the Bolsters to the inner face of the Side Frame between the Stretcher Bars. Glue the other Pivot Post into the top of the Stretcher Plate.
Remove the ejector marks from the axle boxes and glue the Axle Box Covers to them as shown.
For Hornby type couplings glue the adaptor plate to one end of the bogie then cut a small section out of the end to accommodate the hook pivot plate.
Where the Close Coupling System is in use then the top edges of the recess at one end of the Stretcher Plate needs to be rounded to allow the draw bar to move from side to side without catching the bogie.
Close Coupling System
Where the Close Coupling System is fitted then the draw bar retaining plate has to be cut as shown.