Cut the boiler of the BR41 next to the 3rd rim, just in front of the rear steam dome (see figure B), discard the front end. The two halves are assembled. Sand out the joint on top and below the firebox. Using putty, fill up the two carvings for the main air tanks (below the boiler, opposite to the steam dome). These carvings are no longer needed because the boiler will seat higher and clear these tanks.
Cut the boiler of the BR50 next to the 1st rim between the rear dome and the rear sandbox. Repeat another cut just before the front steam dome. Assemble the two halves. This part will become the sand dome and the front steam dome of the 56000. On the driver side, remove the forward / reverse rod. On the fireman side, remove the upper steps to access the sandbox. Sand out the side and adjust to BR41 the firebox. If properly adjusted, everything falls squarely. Once perfect, glue...
Assemble the two halves of the BR50 smokebox. Remove the chimney extension. Remove and file out all the preheater equipment (in front of the chimney). Fill the hole of the steam bell next to the chimney. Remove all pipes and wires from the smoke box. Refer to 56086 pictures and notice that the smoke box is free of wires and pipes. Once perfect, adjust the smokebox to the boiler and glue.
Place the dome covers, the smokebox door, and the turbo-generator.
At this point, you can detail at will the boiler. Being short on time I only did the headlamp because it is an easily recognizable item: replace the "small" German one by a large TCDD style on top of the smokebox door. More courageous modelers can replace all the plastic molded pipes by real pipes made out of wire (steel or brass). This will improve very much the overall look of the model.
Assemble the cab except for the roof and the window glass (other wise painting will be difficult). Start from the boiler end plate and the floor. Once the cab done, glue it to the firebox.
Under the floor of the cab, glue a 1mm thick plastic sheet to compensate for the height difference of the new frame. At this point, you can adjust the boiler to the frame.
It is easy to notice that Revell got the bottom of the firebox all wrong: there is no ash box.
1mm must be taken off the bottom of the firebox to clear properly the 5th driving axle. Close the bottom of the firebox using a flat plastic sheet. Scratch built an ash box that will extend inside the frame: the most important it the "see through" effect of the ashbox inside the frame.
Check the assembly of the boiler / cab / firebox to the frame. All should fit nicely.
A wiew of the boiler and cab.
The steam heating pipe is a very distinctive feature of the 56086. This large pipe starts off below smoke box, nearly in the middle of the frame. Near the main air tank, the pipe makes an "S" shape turn and goes on the driver side of the frame. It will then go below the cab, passing in front of the wheels.
This pipe is quite easy to do using 1 mm diameter wire. The diameter of the pipe is similar to the size of the coupling rods.
Start with the walking board of the BR41. You will notice that this part is too long and needs to been shortened a few millimeters. I adjusted the length with the good old trial and error method: the walking board should extend all the length of the boiler and smoke box. It stops about 2mm short of the smokebox door.
56086 front end view
As is, the buffer beam will not fit the frame. The pockets inside the beam must be modified to fit our narrowed frame.
Then glue the front-end buffer beam to the walking board. I reinforced this bond using scrap plastic glued inside the buffer beam. I shaped the width of these parts to fit also to the frame; this will ease final assembly of the engine.
Our 56000 smokebox is shorter than the BR41 and hardly extends out. The firebox support beams must be adjusted in place accordingly. On the original 56086, the space between the two beams is closed by a sheet metal. This is easy done by using a piece of plastic.
Place the buffers and the hook. Here again, detail at will using new brake pipes, lights, ... The most obvious and highly recommended extra detail it to make a TCDD style cow catcher and attach is under the buffer beam. It can be scratch built using Evergreen 1mm angle beams. This is also an opportunity to rework and detail the underneath of the frame front end.
Adjust the boiler, the frame and the walking boards. At this point, it is good to make a complete trial assembly including the wheels. The buffer beam might not fit the frame at first try. This is now time to adjust the length and the height of the frame under the buffer beam (see earlier in the frame assembly chapter).