We are modifying a Märklin DHG 500 into a Swiss SBB Em, the Em 837 853-1

First of all, the chassis needs to be modified. The third axle has to be moved to the back.

Then we will add all necessary details to make the resemblance with the original loco as good as possible.

We used the blue version of the Märklin locomotive because of the better propulsion.

All of the decorative stripes on the side of the engine compartments were removed. The imitated handrails were also removed.

The handrails on the engine compartments have a diameter of 1mm, and the handrails on the side of the locomotive are 1.6mm in diameter.

At Krüger Modellbau we ordered other parts : radiator grill, stairs to the engine house and to the buffer beams, wipers, factory plate, ...

As already mentioned, we use a blue Märklin DHG as a base. The engine is swapped for a Bühler engine. For this we had to drill 2 new holes to attach the engine.

The base plate itself also had to be changed :  the side pieces of the chassis (we use those of the red versions) are otherwise too high. The bottom plate is cut on a width of 6 cm. This allows the sides to be placed a bit more inwards. This is the case on the red version. On the blue version, one can see that the last axle box is partially milled away and is standing against the stairs. In reality this is of course not the case.

Because the bottom plate has been sawn off, it will be lower against the superstructure. So we have to use spacers to make sure that  the center of the wheel axle  are just at the height of the axle box in the side pieces. We also drilled 2 new holes through all the pieces and then fixed them with 2 bolts. (Crosshead bolts).

One has to make sure that the chassis is correctly aligned with the superstructure.

On the Märklin chassis power was drawn on 2 axles. On the third, middle axle we also placed power points. These are from "Spur 1 Werkstatt" by Rainer Hermann.

Translated with (free version)