I have a Hornby Inter City 125. It is quite old, may be one of the first ones out. Recently it was updated to DCC operation. I was thinking it would look much better if it was lighted. The decision was made. The parts were ordered from YouChoos. (http://www.youchoos.co.uk/)
What was used? Parts List:-.
- 5 x 12 Led stick on strip lights.
- 5 x 680 ohm 1/8th watt resistors.
- 5 x 2 pin plugs and sockets. YouChoos provided the plugs and sockets pre-wired.
- Some 0.5 mm insulated wire in green, blue and black.
- The lead and trailing units require coloured wire as well. Colors will be blue, white and green.
- I purchased some extra strip lighting to obtain the LEDs for the forward ditch lights and tiny gull-wing SMD red LEDs for tail lights.
To start, remove the frame from the body of the coaches. It is not too difficult. The parts are held together by little clips in the end doors. Lay this aside. Take one of the lighting strips. Lay it on the table in front of you with the + sign further away from you. Take one 680 ohm 1/8th watt resistor. With wire cutters trim the pig tails to about 5 mm in length. Using resin core solder and a soldering iron tin both pig tails. Don’t hold the resistor in your fingers during soldering or the heat will burn them. Now solder one end of the resistor to the left side of the (+) rail of the lighting strip. This will be the front of the coach. Solder a piece of blue 0.5 mm insulated wire to the other end of the resistor. On the (-) rail of the lighting strip to the left solder a piece of green 0.5 mm insulated wire. These wires should be about 20 cm long.
Having prepared the lighting strip, take the coach body. Make sure it is clean and free of oil and dust. Peal the cover strip from the back of the lighting strip and stick the strip in the coach body with the wires towards the front marked thus. (*). Note for the Inter City 125 there is no orientation mark. The lighting strip should be in the centre of the roof of the coach as per the photo. Make sure that the strip is pressed down firmly for its entire length. For the purpose of this article the front end of the coach is to the left.
Next we need to mark out on the rear door of the coach a rectangle that is 2 mm x 4 mm. set it so the bottom of the plug will be 8 mm from the floor of the coach. Using a pin vise with a No. 61 bit fitted. Drill a row of three holes in the rectangle along the bottom edge. Stay inside the rectangle. Use the bit to join the holes up to make a slit. With a small file you need to file out the rectangle so the socket fits snugly. I used a file from a set designed for hobbyists. Mine is square sided to file the 2mm ends and has a pointed flat bit to file the 4mm sides. The file I have is a little bit larger than the slot, but with a bit of care and patience it will make the slot large enough for the file to enter.
Once you have the hole completed insert the socket. With the back of the coach to your right and the body upside down the blue wire should be furthest from you. Leave about 1 mm of the plug sticking out of the coach. Using super glue or hobbyistâs plastic glue fastens the plug to the coach. Take care not to use too much glue. It should be glued on the inside so as not to distract from the external appearance of the coach. These glues seep between the joint to form their bond. Make sure the socket is straight before the glue dries. Otherwise it will be permanently crooked. You will have about 20 seconds to get it right before the glue dries. If you take a close look at the photo of the back of the coach you will notice that I used too much glue. It spoiled the pristine look. That was the second attempt to stick it together.
Now we go to the front of the coach. The plug has two black wires attached. Measure 3 cm from the face to the plug. (That bit that touches the socket when attached) Mark this position on the wires. I used white out pen so the line could be seen. In the middle of the front door drill two holes with the No. 61 bit. These should be about 2 mm from the floor of the coach and about 1 mm between them. Using the drill bit join these holes together. Pass the ends of the black wires that are attached to the plug through this slot from the outside. You need to tie a knot in these wires. Take the two wires and tie a single knot. Adjust this knot so that the white mark is in line with the outside of the slot. This length will allow you to get your fingers in-between the coaches to attach the plugs.
It is time to wire everything up. First go to the picture of the coach above. It is the one that shows the completed wiring. Now click on the picture. This will give you an enlarged view. You can see how the wires are installed in the roof of the coach. Once you have had a good look click the browser <- back button. You need scissors and some electrical insulation tape. Cut off a small piece and fasten the wires from the socket to the roof of the coach as shown in the photo. Tweezers will help to place the tape. There should be enough of the wires loose to allow you to have the ends sticking up out of the coach by about 3 cm. This allows for soldering.
Strip about 10 mm of the insulation off the ends of these wires. The next step requires that you adjust the length of the remaining wires so that the knot is hard up against the front door of the coach. The wires go to the roof and are threaded in a small piece of heat shrink tubing along with the blue and green ones from the lighting strip. These wires go along the roof to the ones from the rear. Curve them up to meet the rear ones. Allow about 3 cm of wire length sticking out of the coach once more. With the wire cutters, trim them to length. We need to strip about 10 mm of the insulation off the remaining wires. I used a pair of wire cutters. However there is a chance you might cut the wire short.
Twirl ends of the two green wires together. Twirl ends of the two blue wires together. Twirl the end of one black wire to the green ones. Twirl the end of the other black wire to the blue ones. With a soldering iron and resin core solder, solder the ends. You should end up with two joins. One joint has two greens and a black wire. The other joint has two blues and a black wire. If you wish, trim a little bit off the length of the soldered joints. Cut 2 short pieces of heat shrink tube and place one over each of the joints. Here is where it gets a bit tricky. We want to shrink the tube in place over the joints to keep them electrically separated. No burning of wires allowed. No burning of coach body allowed. No burning of fingers allowed. If you don’t feel confident with this you might consider getting help here or find another way to fasten the tubing in place. What is required is that you have one of those little burners that run on lighter gas. They work like a lighter but the flame is different. Just feather the blue tip of the flame over the heat shrink tube for 0.5 to 1 second. This should be enough. Do one joint at a time. Finish off by fastening the wires in the roof as shown.
That completes the soldering. Leave the coach in two pieces. The next job is to fit the people in the coach. You will have to use the wire cutters to cut off the legs of the figures. If you don’t they won’t fit. Just glue them in place one at a time using super glue. Once this task is finished, you will need to test things. If you already have a loco with an outlet for the coach lighting power use this to test the lights. Notice we did not orientate the black wires when we soldered them. We are doing this now. Just using the coach body plug it into the loco and turn the locos DCC F1 on. If there is light you have it plugged in the correct way around. Don’t unplug it just yet. If there is no light you will have to unplug the coach and reverse the connection. This time the coach should light up. With the coach lighted take a white out pen and make a small white dot across the socket and plug at the back of the loco. Now you have the plug marked so you know which way around to plug it in next time. The white dot on the socket will serve to help you locate the socket to plug it in next time.
All being, well put the coach back together again. Take care that there are no arms or shoulders in the way. What’s that? It didn’t work. Are well you are up for some fault-finding. Note. You can use a 15 v DC power supply to test the coach also. The blue wire should be positive. Check your solder joints as well. Check what I said above about the structure of the connections. That is blue, blue and black joint and green, green and black joint. If you got it wrong it will cause trouble at the next coach. Oh! That’s right you have four more coaches to do. When you get back we will have a look at the power units.
I decided to split it into two here as this is getting a bit long. The next instalment is called “HST 125 unit ditch and tail lights”