I built my original control panel for my current layout in 1990 and the basic design has worked out very nice over the years, it is still very adequate. The actual control panel portion is 24 inches wide and 18 inches high, Big Box stores stock sheet Aluminum and Plexiglas in that size, the panel is angled at a 30° slope.
The entire control panel frame is hinged where it attaches to my layout using two standard household door hinges with removable pins. The frame is made from ¾" plywood and measures 45" W by 28" D, it has two open 9½" compartments one on each side of the control panel. It is supported by a single angled 1" x 2" Oak strut from below. I can easily remove the strut and lower the panel for better access to the center area of my layout. Lowering the panel also gives me access to the rear of the panel where I mounted all the power supplies and transformers so that the heat isn't trapped inside the panel. I have my electronic circuit boards inside the panel, heat and electronics are not compatible.
The right compartment of the frame has a shelf with a Model Rectifier Sound & Power 7000 Controller for operating in standard DC Mode. Below the shelf is a Model Rectifier Advance Square 2 DCC Controller for digital operation. The left compartment is for general storage, small tools, pencils, note pads, etc.
If your a regular follower of my blog you know that I'm a long time CAD user (Computer Aided Drafting). My first CAD program was ProDesign Version 1 back in 1986. For 29 years I've done all of my model railroad drawings on my computer.
This is a printout of my final drawing.
The actual panel is a full size computer drawn CAD printout sandwiched between a .040" thick by 24 wide 18" high Aluminum sheet and a 1/16" thick sheet of Plexiglas. I made several full size prints because the construction process dings them quickly. I tack a drawing to the Aluminum panel with Elmer's Rubber Cement as a template to drill the holes for the switches.
I drilled ¼" holes for mini-toggle switches located on the panel where the function occurs. Atlas Turnout switches are SPDT center off momentary, Tortoise switch machines use standard DPDT, block control switches are DPDT center off for individual block polarity reversing when I operate in standard DC mode. Standard on off functions are SPST switches and there are several LED indicators mounted in chrome bezels.
All the pictures in this post are of the new panel construction.
The Aluminum panel is mounted to the frame with a piano hinge at the bottom and swings open for easy access to all the goodies inside. In the past I drilled holes for the piano hinge through both the Aluminum and Plexiglas, this time I only have the Aluminum panel mounted to the hinge. I used two kitchen cabinet door snap locks to secure the panel when closed.
Over the last 10 years I've made several changes to the wiring inside the panel and I made a major change to the hidden siding inside my mountain last December. I extended the length of the siding by moving two turnouts and adding more track as well as an additional block. Those changes meant it was time for a new panel to accommodate the added switches and move several existing switches to their correct location.
I found out the hard way many years ago drilling Plexiglas with standard drill bits doesn't work without cracking. This time I bought a ¼" Plas-Drill for drilling the Plexiglas and that worked, the drill bit made it easy for drilling holes cleanly through the Plexiglas. I drilled a total of 71 holes in the Acrylic Plexiglas panel without a single problem. Every hole is clean cut without any rough edges.
Do Not Use The Plas-Drill Bits On Any Hard Material!
Before I started moving the wiring over to the new panel I labeled the back of the Aluminum panel with numbers for each component.
I printed two labels on each Avery #6167 (½" x 1¾") label and cut them in half using T for turnout, B for blocks.
I printed a mirror copy of the lighting switch panel and glued it to the Aluminum panel. The CAD program will reverse or make a mirror image without reversing the text, great feature.
Identifying the parts on the back with a mirror print of the panel is a big help and prevents wiring mistakes because of everything being backwards from the front of the panel.
The picture above shows the layout wiring and switches that I removed from the old panel and installed on the new panel. Having done this a couple of time in the past I have learned easier ways of doing things. I believe this is my final panel design so I'm implementing some semi permanent improvements. (nothing on a model railroad layout is ever permanent)
Several switches are in new locations so some of wires had to be extended or shorten.
Using tie wraps is a necessity to keep the wiring neat and orderly. I also use adhesive backed tie wrap anchors to keep everything in place.
One of the improvements is I'm gluing the switches in place on the Aluminum panel with Amazing Goop. With the switches glued to the panel it will be easier to remove the Plexiglas cover to clean and or replace the panel drawing. I've always had a problem removing the Plexiglas because the switches would fall through the holes when the nuts were removed.
The next step is to confirm that the switches are in the correct holes and positioned for proper operation before gluing them in place. To do that I will have to temporarily install the panel and do a complete system checkout of my entire layout insure correctness.
I had one error that was an easy fix and now all the layout control switches are glued in place.
The lighting and power switches are next and I'm going to start over adding several new switches and that means complete rewiring of this portion of the panel. I've modified several circuits and changed out three power supplies in the last few years so this portion has a lot of wiring changes including the addition of a second 50 pin connector.
Before I start installing the switches I need to cut the square holes in the Aluminum panel for the voltmeter and the two 12PST DIP switches that control the individual room lights in Susie's and Doug's houses. Years ago I used a Nibbler to cut clean rectangular holes in Aluminum but I lost the tool in one of our moves. I bought a used Adel Nibbler off eBay to cut the three remaining holes.
The Nibbler is a great tool for cutting sheet Aluminum, it's a slow process but leaves a very clean cut hole.
The panel is ready for final assembly and wiring.
This has been a long tedious project, I'm in week 4 and ready to wire in the new DB-50 female connector in the wooden frame that is the base for my control panel. The two original DB connectors, turnout and block were not changed so they will just plugin and go.
The picture above shows the frame and placement of the power transformers and power supplies.
The Spaghetti wiring will be redone as I finish the installation of the DB-50 connector.
This is a rear view of the completed panel.
Completed Panel front view
The frame wiring portion should have only taken a couple of days but laziness got in the way.
After considering what needs done I decided to basically start over and gutted all the low voltage wire. I will be moving all three low voltage regulators and replacing the solder type bus bars with commercially made screw type bus bars.
This picture shows the frame/box ready for rewiring and cleanup.
Moving the regulators out of the panel area will improve the Spaghetti mess too. The crossing gate controller will end up near the center on the bottom, I will leave room on the left for a second crossing gate controller to be added later.
One thing that will help the cleanup process is using power distribution bus bars. I found a good source for brass bus bars. LED-Switch has a good selection of Mini Toggle Switches, LEDs, Terminal Blocks, DIP Relays and their 3½" brass bus bars.
This is their Brass Bus Bar, perfect size for a model railroad control panel.
I also ordered some Euro terminal strips to use as an interface between the track wiring and the DB-50 connector.
The rats nest is gone, hopefully for ever.
My panel has been checked out to make sure everything works and my layout is back in operation.
It took much longer than I anticipated mainly because of my Arthritis. Other than my pain it really went very well. I still have a lot of work hooking up new accessories but the hard work is done.
I increased the structure lighting capacity from 8.5 volts at 7 amps to 9.5 volts at 15 amps with a new switching type power supply. I used a 35 amp bridge rectifier in series with the 12 volt power supply to reduce the voltage and tweaked it down to 9.5 volts. I operate my lighting at reduced voltage for two reasons, they are more realistic looking and the lower voltage more than doubles the life of the bulbs.
I added a second 12 volt at 15 amp power supply with voltage reducing regulators for 5 volts at 1.5 amps and 4.5 volts at 1.5 amps and 1.4 volts at 10 amps. The 5 and 4.5 volts are for circuit boards and controllers, the 1.4 volts powers my vehicle micro bulb headlights. I have close to 90 vehicles with oporarating headlights, taillights, running lights and miscellaneous flashing micro bulbs.
It was a great project that should last for many years.