The CINDER. the CINDER CRUNCHER CRUNCHER. ID Meet INTERNATIONAL DIVISION N.M.R.A

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1 The CINDER March 2011 the CINDER CRUNCHER CINDER CRUNCHER INTERNATIONAL DIVISION N.M.R.A the CINDER CRUNCHER page 6 JAN At our October 2010 meet, we held a "Build a diorama on a CD" contest. We didn't have time to judge it and also realized we didn't clearly describe the rules. So, we are doing it again at this meet. Here are the rules. 1- The scene modeled must be railway related. 2- Scene can be of any nature, topic, realistic, or comical. 3- Scene must be modeled on a standard 4 ½" CD. 4- All components of the scene modeled must be within the outside diameter of the CD (no height restrictions). ID Meet Mar. 12, 2011 Burlington Central Library 2331 New St. Burlington, Ontario Library opens and registration starts at 9:00 AM Meet begins at 9:30 AM NMRA members: $3:00 Non-members:$5:00 Marty Gold's clinic on "DCC Decoder Selection and Installation Basics." Roger Chrysler' s clinic on "Using card stock building construction techniques to represent the rears of businesses facing the railway, rather than the fronts along the main street." Layout Open Houses Ron Robinson Bob Mitchell Charlie Olden

2 the CINDER CRUNCHER page 24 Aug 2001 the CINDER CRUNCHER page 2 the ID EXECUTIVE Superintendent Harvey McIntyre , 1 Royal Wood Crt.,Stoney Creek, Ontario, hmcintyre4@cogeco.ca Assistant Superintendent George Ziemer ,186 San Francisco Ave., Hamilton, Ont. L9C 5N9, gziemer@mountaincable.net Clerk Richard Sparrow, , P.O. Box 8, 1278 PelhamSt., Fonthill, ON, L0S 1E0 rands.sparrow@sympatico.ca Canadian Paymaster Jim Tucker, , 31W81 Pettit Road, Wainfleet, ON, L0S 1V0, j.tucker@rogers.com American Paymaster Doug Nagel, , 5143 Shunpike Road, Lockport, NY 14094, RRoadEng@localnet.com Registrar/Terminator Michael di Pota, , 1430 Forbes Dr., North Tondawanda, NY, 14120, khwahkhwah@aol.com Webmaster Walter Reid,wtreid@sympatico.ca Achievement Program Bob Willer, MMR, , 11 Woodstock, Grand Island, NY 14072, RWILLER@NStarDesign.com Cruncher Editor Chuck Faist, 5209 Alton Road, Burlington, ON, L7L 3H4, cfaist@cogeco.ca The Cinder Cruncher is the official newsletter of the International Division, NFR, NMRA and is published before each Meet or as needed Classified advertising is available to ID members at no charge. Ad must be as brief as possible. At our October 2010 meet, we held a "Build a diorama on a CD" contest. Please bring a model to display whenever you can.

3 the CINDER CRUNCHER page 3 Photos from our October meet. PAYMASTER'S REPORT Canadian Paymaster, Jim Tucker, reports that we have a total of $

4 the CINDER CRUNCHER page 4 Bob Mitchel 2542 Boros Road Charlie Olden 1497 Clinton Court Ron Robinson 1107 Marley Cres. Library 2331 New St.

5 Installing Turnout Position Indicators using Tortoise Switch Machines by Richard Sparrow First, the let me CINDER say that I am CRUNCHER not an electrician, nor have I ever had any formal training in electricity save High School physics courses many moons ago. This is given as a caveat, in that there may be better, faster, cheaper ways of doing this. However, the method that I describe below works on my layout... and it impressed my grandsons! One of my current projects is the 'Engineer Electrical' certificate for the NMRA Achievement Program. Section 3 of the requirements lists twenty-two different electrical options that can be included on a model railroad, and for just three of these the candidate has to wire and demonstrate the electrical operation of them. Then Section 5 requires that a circuit diagram of each be drawn. Even though finding three items from the list of twenty-two was not a slam-dunk for me, the turnout position indicator option was not on my short list it just sounded too tricky. Then one day, idly leafing through an electronics supply catalogue, there were some bi-colour (red/green) LEDs. With a quickening heart rate, I thought to myself, self I thought, these would probably be ideal for making turnout position indicators! When putting a bit more thought into this, I felt they would not only help with the Achievement Program requirements, but would also serve a really useful purpose for the Smithville section of my layout, as there are several turnouts on hidden track, as represented by the white lines on Fig.1 below, including the double track reverse loop. Decision made! After scanning through the catalogue for a few more items to make it worthwhile for the postage, I keyed in the order, cyber-swiped my credit card and sat down to wait. A couple of weeks later, the package arrived in the mail with enough bi-colour LEDs and 470 Ohm resistors to do nine of the turnouts on my Smithville panel. Why 470 Ohm resistors? Well the LEDs are made to operate on 3V and I was using a nominal 12V supply, which actually put out 15V when measured on my multi-meter. Using Ohms Law from High School physics yesss! (ably assisted by the website ). Hey, as I said, High School was a long time ago! - I keyed in the following values: Source voltage, (V S) 15 V. Voltage drop from the LED, (V LED) 3 V. Current through the LED, (I LED) 30 ma (an estimate based on specs given for other LEDs in the catalogue) Hit the 'calculate' button, and the program filled in the required resistor values of 400 Ohms and 0.36 Watts. A 470 Ohm resistor would tone down the LEDs a bit, and 0.5 Watts is the next power size up from 0.36, and so that is what I chose. Since completing my installation, I have learned that the current draw (I LED) of this type of LED could be closer to 10 ma, and using the same on-line calculator, this suggests resistor values of 1200 Ohms and 0.12 Watts. While the 470 Ohm resistors are working right now, using a higher value resistor will run the LEDs dimmer, but they will last longer. The idea is that on the control panel track diagram, a bi-colour LED is placed in the main route leading from the turnout in most cases. When the turnout is set for the main route, the LED is green, when the turnout is thrown for the diverging route, the LED is red. The toggles on the double-pole-double-throw (DPDT) switches used for my Tortoise switch machines are mounted to align with the open turnout route thus indicating which way the turnout is thrown. Even so, the coloured LEDs show this more clearly at just half a glance. Fig. 1 Smithville Panel showing the red and green LED Turnout Position Indicators

6 An alternate way to set up the position indicators would be to have LEDs in both the main and diverging tracks leading from the the CINDER turnout on CRUNCHER the panel diagram. The LED on the open page route 6 would be green, and on the closed route it would be red. The colours would reverse when the turnout is thrown. However, I find the single LED per turnout serves the purpose, and does not clutter up the track diagram as much. The bi-colour LEDs I used are 5mm diameter, three legged variety. These have a center cathode, and 1 anode each for the red and green display. They are operated with a single-pole-double-throw (SPDT) switch, and as the Tortoise switch machine includes two sets of SPDT contacts it makes it simple to wire. The second set of contacts on the Tortoise switch machine, contacts #5, 6 and 7, is used to activate them. The first set of SPDT contacts, #2, 3 and 4 is used for frog polarity which is also shown on the circuit diagram, Fig. 2 below. For the 12VDC supply to the bi-colour LEDs I use my Switch Machine bus line. This minimizes the length of wire to be run from the switch machine to the panel. To make a neat installation of the LEDs, I ordered two piece holders for them. The LED snaps into the center portion, and then this sub-assembly fits inside an outer sleeve, providing a tidy bezel look from the front of the panel. The outer Sleeve is about diameter, and so a 3/8 drill (0.375 ) was used for the holes in the panel. The fit was not quite tight enough to hold the LEDs firmly in place, and solving this problem which on the face of it seemed simple enough, turned out to be quite an adventure Recently, silicone adhesive has been my adhesive of choice for joining dissimilar materials as an alternate to 2-part epoxy. It is used straight out of the tube, and does not get crispy hard so that it can crack and release in a few years. Not silicone caulking, but silicone adhesive. It is usually found in the automotive section of your favorite hardware store. Applying a good dob of adhesive to the back of LEDs and holders inside the panel should keep them nicely in place I thought, and so it did. However, getting the stuff down in between all the wiring that goes with the Tortoise DPDT turnout control switches, and the newly added LED wiring, without coating everything with this sticky goo was quite a task. After coating the backs of all nine LEDs on the panel, and adjusting them from the front of the panel so that they all stuck out the same distance while the silicone set, I switched the power on to admire my handiwork nothing! Not one red or green light was in evidence. This kind of thing sometimes happens to me, and most often it is a simple fix. This time, unfortunately, I went with the first thing that popped into my head maybe it was late and my battery was running low, but that one solution came to me, and before taking time to consider other possible causes, and wanting to see this project through before quitting for the day, I got right down to fixing it! I bet silicone adhesive is a conductive material, and I have shorted out all the LEDs, after all it is kind of a semi-liquid! Now, if putting the silicone in place between all the switches and wiring was difficult and messy, it was nothing compared to getting it all back out again. After trying in vain to clean the silicone off the LEDs in situ, I gave in and unwired them all, thus being able to take them out of the panel and clean them off more thoroughly. Once this was done, after much time and a goodly quantity of kitchen roll towels, I wired the LEDs back in, turned on the power again, and presto nothing, no green lights, no red lights. Oh boy! Desperation was starting to set in. While groping around in the wiring to find I don't know what, a miracle at least I guess, I happened to notice that there was a wire hanging free, not attached to anything. It was a blue wire blue is the colour I use for one side of my main switch machine bus! Maybe that has something to do with the lights not coming on,- do ya think! In rooting around in the wiring to apply the silicone adhesive in the first place, I had unhitched this wire from its mooring. Now, when I remounted the wire in its correct terminal strip spot, all the lights came on, and they also changed colour when I flipped the turnout control toggles ah, how sweet it is! With my energy spent for this day, I resiliconed them all the next morning, and they still worked! As shown in the circuit diagram, Fig. 2, the wiring is as follows: Contact #5 to the 12VDC negative supply bus Contact #6 through the 470 ohm resistor and to one of the outside legs on the LED Contact #7 to the other outside leg of the LED The Positive lead from the 12VDC supply bus goes to the common leg of the LED If the LED lights up green when the turnout position indicates it should be red, and vice-versa, just reverse the wires on the two outside legs of the LED. If the LED does not light at all, then reverse the leads from the 12VDC supply bus, i.e. connect the Positive 12V supply lead to #5 contact on the Tortoise switch machine, and the Negative 12V supply lead to the common leg of the LED. Turnout Position Indicators, but maybe use CA adhesive to secure the LED holders to the panel!

7 If you are looking for any easy way to impress your grandchildren, and get positive feedback on turnout positions, and especially if you are working on the Achievement Program, Electrical Engineer - try putting in Turnout Position Indicators, but maybe use CA adhesive to secure the LED holders to the panel! Fig. 2 Circuit diagram for Turnout Position Indicators using Tortoise switch machines

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