Improving the HOrnby acHO STEF refrigerated wagon (2)

Original page created on 02/05/2013; updated on 14/02/2024.

Working on existing parts

Dismantling

Simply remove the two coupling pivot screws. Separate body, chassis and ballast. The ballast, the couplings and their screws will no longer be used.

Work on the chassis

  1. Remove the centre struts of the chassis tie rods (Fig. 1)
  2. Cut the eight brake blocks with a disk saw blade
  3. Fasten the chassis by the coupling holes on a good quality plywood plate, i.e. of constant thickness (I had surprises!), with ⌀ 2.9 Parker screws (interpose a piece of thick cardboard or hardboard also of constant thickness to the ballast approximate dimensions to serve as martyr, and to distribute the effort on the largest possible surface). The purpose is to machine the chassis with the Proxxon XY table, on which I therefore fix the plywood plate with the chassis
  4. Drill ⌀ 2 holes in the axis of the buffers (before cutting them), the drill being rotated by 90° with respect to its support (Fig 2). Drilling before cutting the buffers helps to centre and align the holes
  5. Cut the four buffers with the saw disc, the drill being in the same position as before (Fig. 3). If necessary, correct the flatness of the buffer beam with a file or a mill bit
  6. Hollow out the axle boxes at ⌀ 2 with a ball mill bit 15° tilted, to about 2 mm deep (Fig 4). Attention: the drill is tilted, not the displacement axis, which must stay vertical
  7. Mill the brake block and coupling brackets level with the floor (remove the fastening screw when coming close). Remove the floor between the already open part and the buffer beam, leaving approximately 5 mm along the buffer beam (do not mill too close to the buffer beam because the piece between the vertical backrest reinforcements would no longer be held, and it would be made fragile)

Removing the centre struts

Fig. 1

Drilling the buffers

Fig. 2

Cutting the buffers

Fig. 3

Hollowing the axle boxes out

Fig. 4

Why remove part of the floor? I have found that if the flatness is not perfect, the Roco drawbars may become blocked. So, they will be fixed directly to the ballast plate, which is perfectly flat (see below).

Work on the body

  1. Remove the ladders (for this, unfasten the straps inside the body)
  1. Drill the ramp holes at ⌀ 0.4 (Fig. 5). Caution: the lower holes must not pass through the pillar from the outside! The ideal would be to make blind holes cut the ramps to the exact dimension
  2. Possibly, mill the board grooves where they were not made to facilitate the marking: registration, “REFRIGERANT” marking. The groove spacing is 1.44 (end faces) or 1.49 mm (side faces).
  3. Possibly, mill the door handles, then drill the ramp holes (center distance 4.4 mm) to ⌀ 0.4

Fig. 5

Drilling the ramp holes

  1. Plane the old couplings threaded columns down to the bottom of the body. Re-drill them to ⌀ 3, depth about 10, then forcefully insert a piece of 6 mm Bic pen cartridge.