More Chudleigh Road

For those of you in need of more rambling about my layout, there is a thread on the RMWeb forums about Chudleigh Road.  I'm trying not to exactly duplicate the content between blog and thread, but it turns out that I'm not terribly good at that.

Guess what? Soldering!

I want to have the control panel finished before I start any scenic work on the layout.  I'd rather not have to keep turning it upside-down with too much built on top of it.  This means that I have to crack on with the control panel.

The next stage is to solder up all the switches and LEDs.  The LEDs I bought came in mounting assemblies but without ballast resistors.  Each LED had a resistor soldered on, followed by wires long enough to reach to the chocolate blocks from the 25-pin connectors.  The switches just had wires soldered on.  By the time I'd got through this my trusty wire strippers had collapsed and I had to nip round the corner to Maplins to buy a more robust pair.

All in all, this took several weekends.  I hope it works.

The control panel takes shape

After taking a lot of care while building the baseboard, I got a little overconfident.  The control panel is a story of measure once, cut several times, then squeeze everything in as best as possible.  I planned the mimic diagram to be A4 in size, which I had imagined would give me a lot of room to fit things in.  After I'd bought and cut a sheet of perspex it became apparent that this was a little optimistic.

In the end, I managed to squeeze things in.  The main constraint was that the switches and LED mounts I had bought needed 6mm holes in the panel; this meant that I couldn't shrink things too much without them getting crowded together.

The idea was that the top of the panel would be made from a sandwich of 3mm perspex, a paper printout of the mimic diagram, and 3mm plywood.  Looking the LED and switch mounts, I discovered that they would fit through something so thick and still have enough thread visible to attach the mounting nut.  Replacing the plywood with 1mm plasticard solved this problem.  The next step was to ensure that I could actually make 6mm diameter holes through the sandwich.  Some internet research suggested that a good way to drill through perspex without cracking or melting it is to use tile and glass drill bits.  Off I went to  Amazon to buy a set of bits .  I used some off-cuts to test the process.

Success! Now to drill 54 holes in perspex without cracking it.

Remarkably this worked as well.  By the end the bit seemed to be getting much less effective.  Either these bits are of poor quality or perspex takes its toll on them quickly.

I made up a frame from some spare 2"x0.5"ish timber that I had knocking around from an old bookcase and used this to mount the diagram sandwich.  My hope was that this would give enough space underneath to accommodate all the wiring.

More soldering

The control panel with mimic diagram and switches for controlling the point motors and track feeds will have to be separate from the layout, otherwise it won't fit under my son's bed.  Here the large number of points makes for doubly hard work - the panel is going to have connections going to operate the point motors as well as connections coming back from them to feed LEDs.  As a result, I need three 25 pin connectors on the panel and baseboard to connect the two.  This doesn't include the connections from the Gaugemaster twin track controller or the power feeding the track, for which I am going to use some 6-pin DIN connectors.

All this amounts to yet more soldering, which has kept me busy over several weekends.

The 25-pin D-Sub connectors will be fitted into the side of the control panel, and the wires from them will go into chocolate block connectors.  The hope is that if something goes wrong this will make it easier to diagnose and fix the problem.