12/03/05 rev 01/16/07
CONTROL PANELS- DO WE NEED THEM?
Once upon a time, model railroaders seemed to delight in building big complicated control panels so they could be master of their empire and run it all from a central location. This sometimes involved elevated operating positions on bigger layouts. As time went on this became passe and "walkaround" operation become more popular. You could follow your train with plug-in, and later radio, cabs and DCC. Remote controlled switch machines became less popular as the walkaround crew was adjacent to the turnouts that his train was using, so why not just use a handthrow. Ultimately many layout builders argued that they had NO need for control panels. As I see it, there is a middle ground. A large yard can be a pain to reach into for a handthrow. Many handthrow gadgets do not have the capability to switch a "hot" frog. I DO NOT use dead frogs!!
Even when we achieve prototype operation with a full-time Dispatcher there is need for control panels or control devices in the field.
After building panels for nearly 60 years, I believe I've developed a good technique that is reasonable for most of you to follow. I make no claims to exclusive design as we all learn together. Let's look at the construction of the new Malfunction Junction panel that replaced an old one used since 1978.
First requirement: You should have the ability to develope artwork on the computer. I use ACAD, but there are many programs that will do the job. The critical factor here is to build a picture that can be printed now and again in the future while acurately maintaining it's dimensions. Here is the picture I used for MFJ. It prints out to exactly 7" x 17" in two overlapping pieces.
If your art or cad program can work in layers, you do have an advantage in layout. Above we see a WORK copy and below we see the actual insert for the panel.
With the artwork complete, we need material to build up a laminate. This panel used two layers of 1/8" micarta sheet and a top layer of clear 1/8" plexiglass sheet but I could have used 1/8" plexiglass for all. I carefully stack all the layers with the work sheet taped on top. I mark drill holes for push buttons and switches with a sharp pointed hot solder iron. You might choose to use a small drill but a punch is a NO-NO. it will shatter plastic I do not drill or mark the top plastic where a lamp or LED will be. The first holes to be drilled to size are the are the four corner mounting holes. I usually use a #6-32 or #8-32 bolt. Now we can bolt the whole stack together. Next, drill a small hole through the stack at the center of each device EXCEPT where LEDs or lamps will be. Remove the top clear sheet before drilling these as they will just shine through and it eliminates a dirt trap.
Next- drill all sheets to clear the shank of switches and pushbuttons.
Set the clear top sheet aside
clear top 1/8" sheet
Drill the two lower sheets slightly undersize for LEDs and lamps. Finish the holes with a taper reamer so the LED/lamp is a snug fit. We are going to glue them in with ACC.
bottom 1/8" sheet
The PB and switch holes in the middle sheet are now enlarged to clear mounting nuts, thus hiding them from view when the paper plot is installed.
middle 1/8" sheet
Finally, assemble the paper onto the top sheet and use a jewelers jewelers round file to poke holes in the paper and trim them to line up with the device holes. You still need to punch holes in the paper for LEDs and lamps. For this, I sharpen the end of a 1/8" brass tube and use it as a punch with the paper lying on a resilient material. A gentle tap cuts a perfect circle out.
I've used this technique for numerous panels of all sizes, at home here on the Teton Short Line and at our HO modular club. Their are several of them at the Pocatello Model Railroaders Club that have been modified many times just by calling up the old file and changing it. When the top sheet gets too messy with changes, just make another with your saved pattern. Abandoned and modified holes in the middle and bottom sheet are completely hidden. In some cases, I've plugged and redrilled holes. With implemenation of DCC, some panels have had most of their toggle switches removed, but you can't see the old holes behind the NEW paper insert.
To finish things up. Here is the hind side of the finished panel. Notice that all connections are made through the salvaged Telco 50 pin connectors. Small pads of PC board glued in place make handy splice points where the LED resistor meets the wire. I make all TSL panels at the bench and use connectors for ease of removal. Our Staging yards use a similiar technique crowding lots of devices in a 4.5" x 10" panel. Even the simplest panel with four buttons and LEDs for a siding use the same technique.
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