Atlas RS3 conversion to a D&H RS3

To see the finished model click here

Several years ago I built a RS3m out of an Atlas RS3. A lot of people asked me how I did it so, I thought I would do a step by step explanation of how it was done. The engine is an older yellow box undecorated unit, but the newer Master Series engines can also be used. The conversion kit that I used is made by Tiger Valley models and is a die cast metal kit. The kit is very complete and includes a detailed instruction sheet. However, one caveat should be made here. This kit was designed for the Model Die Casting RS3's and some creative interpretation of the instruction sheet is needed to use it with an Atlas as the MDC RS3 is different that the Atlas model.

The victim... an ordinary, run of the mill RS3 engine from Atlas

The first step is to disassemble the engine. I did not do a photo sequence as the instructions do a fair job of showing this. The cab section comes off of the main part of the body by releasing the tabs inside of the cab that are attached to the window glazing. Once the cab section is removed the window glazing needs to come out. Now it is time to start the cutting process. There is actually very little that needs to be cut from the cab section. I marked the cab to show where this is. Make sure you cut the material from the front side of the cab. The cab is not reversible.

The black mark shows where to remove material

I found it convenient that the opening in the front is the exact size needed to fit the new nose piece. I use this as a guide when cutting the opening higher and use a small pair of flush cut nippers to cut the area between the two center windows.

At this point the new nose section should fit snugly in the opening

Once you have removed the material from the opening test fit the new nose section and file the sides so it will fit with no gaps. Also, file the lip off of the two center windows on the cab section to give this area a level surface to mount the number board to. There is a stepped section that will guide you for placement of the nose section. Place the two parts on a flat surface to ensure that the nose will fit properly. When these parts are assembled they should both sit flat. Do not worry about the area above the center windows as this area gets covered with the new number board / headlight part. If you are satisfied with the fit, it is time to glue the two parts together. I use ordinary super glue to do this. Before I glue though, I make sure both parts are clean and I will run a fine tooth file on the mounting surface of the metal part to ensure there is nothing to compromise the bond. Set this part aside to dry and begin work on the main part of the shell.


The shell will require the majority of the cutting. The first area we will work on is the nose section. The other cut needs to be made to the area right behind the cab to allow for the Dynamic brake housing. For now we will just work on the nose. I have marked out the area that we will be cutting off of the shell.

The first cut will be made in front of the hatch marked area. Cut straight down from the back starting just inside of the forward cab wall mount area. This will completely remove the nose section and allow for the new nose section to fit. I have found that a piece of 3/4" plywood will fit snugly inside of the shell to help with the cutting. Using this method allows you to clamp the sides with your fingers and allows the saw to cut cleaner. I also remove the hatch marked section on my models to give my cab sections more room. This is an optional step.

Notice that I left the rear cab mount lip in place and two "arms" along the bottom of the cab section. This is so that I can glue the cab to the shell when I do the assembly work. Next, I will start work on cutting the opening to put the dynamic brake housing in.

I will continue this project in next weeks installment.

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