To paraphrase Vane Jones, "Knowledge is of little value until shared with others."

Wednesday, January 1, 2014

North Shore Line 409 - Part 8 Cutting Out the 2-Window Panel

Happy New Year - 2014!

To prepare for cutting out the 2-window blank panel, look at the drawings of the 409 as printed in MR. Then, look closely at the model to determine how much must be cut out. Also, look at the windows around where the cut-out will be. Conveniently the upper edge of the cut-out needs to be at the lower edge of the letterboard. Run a finger over the window post up to and over the letterboard. You should feel a slight hump about the top of the windows. The opening needs to start just below the hump.

Next notice the window sash ends just above the horizontal belt rail with rivets. The bottom of the window sash, the lower edge of the cut-out, is at the top of the the belt rail.

The sides of the windows end next to a slightly elevated post between the windows. The sash of the windows is next to this raised piece. This is a photo of a sample of windows in the side of the model. What look like little white dots are rivets.

This is a photo of the area to be cut out. Notice and compare the top and bottom of this area and the windows. Notice the sides of the area to be cut out ends with a single row of vertical rivets. When the panel is cut out the 2 rows of rivets (1 at each side) at the sides of the panel will be gone.

Before cutting out anything, how are the windows going to be built? Are they going to be built in place? How are they going to be supported on the sides and back? Are the pieces making up the window going to be pre-painted or painted after the window is built or inserted in place? What kind of material will be used to build the windows?
In answer to these questions a decision was made to build the windows out of styrene strips. Styrene is easy to work with and comes in various correct size, scale shapes. However, it does not have great structural strength in the sizes to be used to build the windows.
The windows will be built in a "form" the same size as the cut-out in the side of the model. After the glue had cured. the windows will be popped out of the "form" and painted a color matching the red of the model.
To answer the structural strength problem of styrene, the pre-painted window will be "glued" in place. The new windows will be backed (glazed) with clear, styrene much the same as the models window glazing. If required the new window can be glued to the glazing.
Now you have an idea of how the new windows will be added to the model. Keep in mind the area will be cut out and then filed "square" for the pre-painted windows to be inserted and glued in place. The operative word is "square". Filing metal, or other material, square is not easy. It requires time and work.
The 1st cut into the side of the car was to get a feel for how thick the brass was in this portion of the side and how hard it would be to cut the hole into the side. The cutting was done slowly so the brass did not get too hot. Heat destroys the finish and will weaken glued and even soldered seams.
It wasn't too difficult to cut the hole with a cut-off wheel. A white sox on each side of the area being worked on can be seen. The sox were a great help with holding the model. I didn't have to worry about where the model was grabbed and what would happen to the model. 
Four holes were drilled in each corner of the area to be cut out. The 2 horizontal cuts were completed into the holes.
Take note of the amount of brass filings left from the 2 cuts. Always blow or brush-out these filings before going further. A small vacuum cleaner would be handy. Do not let the filings build up. They can scratch the finish and glazing on the model. The 2 vertical cuts were next.
The horizontal cuts were made with a larger 2-1/2" or 3" diameter  cut-off wheel. The vertical cuts were made with a smaller cut-off wheel. As a cut-off wheel is used it becomes smaller in size. The smaller wheels are saved for close-up work where a large wheel would not fit.
After the 4 cuts are made what is left of the panel fell out. The outer piece is painted red. It was 0.025" thick. The unpainted panel is the inner piece and was 0.015" thick. From the fact the 2 pieces fell out free of one another tells me the 2 pieces are soldered only at their edges where the 2 pieces join. The effects of soldering flux (the pink color) can be seen on the inner piece. The back of the inner piece of brass was painted the same as the interior of the car - a light mint green.
Let's stop here and pick-up the finishing of the hole in the next post. A problem arose which will be explained in the next post.

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