KingEdwardII

I've not had any problems with my Prodigy Advance2, but it is less than 1 year old. Mike

The WWI ROD 2-8-0s are discussed in David Maidment's "Great Western Eight Coupled Heavy Freight Locomotives" book - Chapter 6. He's a bit vague about shed allocation in BR days, excepting Carmarthen where he has specific allocations described for the period up to 1958. The numbers he lists are always in the 30xx range, even in BR days. Mike.

You're now into the space of "regular" electrofrog design. To prevent shorts, you must put insulating joiners on the rails leading from the frogs - the track beyond those insulating joiners must be fed power independently. Strictly, this is all that you MUST do. But as discussed previously, a design that has both switch rails with the same polarity as the frog is prone to shorting between the stock rail and the switch rail. This leads to the idea of cutting the wires between the switch rails and the frog as in your diagram. This results in the frog needing its own power feed, which must switch polarity when the point is switched. If the point is operated by a point motor, most of these can have a switch that can be used to provide the correct feed for the frog (switch is either built in or can be added as an accessory to the point motor). If the point is operated manually, it is necessary to have some form of mechanical switch which is moved when the point is switched. In the case of DCC operation, it is also possible to use a frog juicer device like the Gaugemaster DCC80, where there is no mechanical switch and the frog polarity is organized through electronic technology. Finally, bonding wires can be added to the switch rails as shown in your diagram, to overcome any poor electrical continuity between the switch rail and the corresponding stock rail. Mike.

Yes, laying track well is a slow and painstaking business - even more so when you add in point motors and the mechanical & electrical aspects of those. That is one reason why I really appreciate the track layout software. You can build an accurate model of your layout quite quickly - see what works and what doesn't work in the space available. You can chop & change, try out multiple "what if?" alternatives. I like the ability to impose a minimum radius for curves, with the software giving you a warning if it gets breached by your design, allowing for some replanning. You can try out the effect of different choices for pointwork - it is especially valuable for the software to have accurate models for the pointwork you are using. I think I prepared 15 versions of the track plan for the layout I'm working on at the moment and I've only made a couple of minor tweaks while laying the track itself. Mike.

Wordsmith, I use all pinning & no glueing. My approach is to use track layout software (xtrkcad in my case), print out the layout at 1:1, stick down the printouts and then lay the track, pinning it in place to match the position on the printout. For curves, I usually start at one end where there is already a piece of pinned-down track and then work my way along, pinning every 11th sleeper or so - the tighter the curve, the smaller the gap between pins. When I'm done, I trim up the rails using my Dremel, since the curve means that one side will be longer than the other. Avoiding joints on the curve is a good idea but in a layout with more relaxed curve radii, they become inevitable. I usually aim for some pre-bending of the rails around a joint to avoid getting a discontinuity in the curve. I much prefer using the software-and-printout approach since it makes it easy to use curves which are not circular in form (ellipse, Bezier...) and where the radius of curvature changes as you go round the curve. Once the track has been pinned down once, it is easy to lift it, remove the printouts and replace the track ready for ballasting, etc. Mike.

Why not treat the two lines coming out of the terminus as two single lines rather than as a double track? I am prompted to suggest this since this is in fact the organization of Aberystwyth station until the 1960s. One of the single lines ran to Carmarthen while the other went to Shrewsbury. Aberystwyth had an MPD with a triangle for reversing engines between those single lines, rather than a turntable. The triangle was however separate from the main running lines and was closely associated with the MPD. And in case you think that Aberystwyth might have been on the small side - in reality there were 5 passenger platforms and a substantial goods yard. Platforms were quite long allowing for trains with substantial numbers of carriages. Operations got "interesting" on summer Saturdays...

Indeed. The prototypes seem to vary a lot with respect to the distance between the dolls. In cases where the arms are at different heights, they can often be very close together. It seems fairly typical to allow a bit more space in the cases where the arms are at the same height. I assume Ratio have chosen the common case where the heights are different, but it is a pity that they don't make any provision for some variation in the doll spacing with this kit. I think that the round post version (Ratio 468) provides more space between the dolls. Yours, Mike

How does your system compare with a system using a motor shield combined with an Arduino board or Raspberry Pi? Yours, Mike.

How are you building the DCC Controller? Which technology are you using?

I don't use solenoid motors - I use MTB MP1 motors in the main - slow action. I switch pairs of points like crossovers using a single channel on my DCC accessory decoder (Digikeijs DR4018 in my case). Works a treat, 100% reliable. The current draw of these motors is fairly low - max 150mA - so that a pair never tries to draw more than is available from the accessory decoder. Yours, Mike.

Wordsmith - I'm glad it's working out for you. Regarding the soldering, for "small" jobs like soldering dropper wires, I never hold the solder wire. I leave a roll of it on my workbench with the end pointing upwards and then rub the tip of the soldering iron across it when I'm ready to do the work. The tip collects more than enough solder for a small job and that leaves me with a hand free to assist getting the wire and track positioned. I'm not against using croc clips to hold things, but I'd only hold the solder wire for jobs requiring large quantities of solder - more in the plumbing line ;-) As for flux - I have belt & braces approach and apply flux to the work and also use flux solder - I don't get any failures of my solder joints. Tracklaying is steady work and you need to take some pains with it to get smooth running. I've moved over to a system of using track layout software (xtrkcad is my current program), getting the design sorted out on there and then printing out the design on paper at 1:1 scale, which I then stick down to the baseboards and use as a guide for laying the track. The design software helps ensuring that things fit together properly and that you avoid curves being tighter than necessary - xtrkcad lets you specify a minimum radius and then gives a warning if that radius gets breached anywhere. The software also lets you play with variations like changing between different radius points.

Iain, I think you have a great idea for us collectively to put together a set of info on the various busses. I think that given that the topic here is "automation", this info must include some details relating to some of the pieces of software used to achieve the automation. e.g. If you have iTrain + XpressNet, what set of capabilities are going to be possible? I don't think we should swamp this with too much detail on the software, but knowing that a particular combination can provide info on the location & identity of locos on the track (say) is something important to know when you're planning a system. Yours, Mike.

Mine has arrived - very neat piece of kit. Some pictures of my Pi 400 package as delivered from The Pi Hut. The two boxes contain the mouse and the power supply. All the connections are at the back of the keyboard, excepting the WiFI, of course: I show the legend for the connectors, as printed on the box. The MicroSD card comes already installed in the slot - this contains the operating system. I need to add an HDMI connected Monitor and a USB attached SSD drive for data etc. Yours, Mike.

PS Now for more of the red stuff. My favoured tipple is a Barossa Shiraz, say a St Hallett.

I'm glad you've fixed the problems, Roger. No doubt you have also learned plenty as well, which is all part of the fun. Yours, Mike.

Roger, If your picture shows the multimeter measurement places correctly, then I think that the left hand point shows that the frog has the wrong polarity when the turnout is set to the diverging (i.e. curved) route. In this case, the extreme left measurement should be 0V, i.e. the frog should be the same polarity as the bottom stock rail - but it is showing up as 18V. So as your loco passes over this turnout, once the driving wheels straddle the gap between the lower switch rail and the frog, 18V passes across the driving wheels on that side since they are electrically directly connected. Result: a short. You need to examine the mechanism for providing the feed to the frog - it isn't working correctly. I think you said that you're using Cobalt iP Digital point motors - you should cross-check your wiring with the iP Digital manual - it looks like terminal 3 is the feed for the frog, while terminals 1 & 2 are the DCC input. It may be that you need to swap the connections to terminals 1 & 2 to get the correct polarity. I'm not a Cobalt user, although the MTB MP1s that I use do have a similar kind of arrangement and it is possible to get the polarity the wrong way around. I find that my multimeter is my best mate when wiring up the layout - and I check all the polarities and voltages before I let a loco loose on the track. Good luck, Mike.

I've ordered a Pi 400 from Pi Hut - I've been thinking about buying a Pi 4 for some time, but I was fretting about the required cooling arrangements. The Pi 400 solves this aspect and the integrated keyboard concept is very neat. I plan to use mine not only to run model railway software, but also as a server for our house, running 24/7 with a large capacity SSD attached. I also fancy the idea of attaching a large touch screen (> 22 inch) and using that rather than the mouse for interaction. I'll report back on my progress. Mike.

Roger, Looking at your most recent pictures above, and the fact that you get separate shorts for District 1 and District 2, I think that the problem is most likely caused by the frog of each point having the opposite polarity to the curved switchblade. I say this since it is suspicious that the loco driving wheels appear to straddle the gap that exists between the curved switchblade and the rail leading up to the frog, in both cases. It should be straightforward to test this hypothesis with a multimeter - check if there is a voltage between those two positions on the track - it should be zero. If there is a voltage here, then the power feed to the frog is wrong and needs switching over. Mike. PS. Which red is in your glass??

Likewise - I drill 1mm diameter holes in sleepers for the pins. I have a standard cordless Bosch drill with keyless chuck and it has no problems gripping the 1mm drill bits. I have both ply and MDF in my baseboards and I've never needed to drill pilot holes to drive home the pins - I use a small & lightweight jewellers' hammer to avoid damaging the pins & hold the track pins with tweezers while hammering them in to keep them vertical. Yours, Mike.

Leon, Assuming your new layout is going to be static in the one room, I can recommend building some very simple legs out of planed timber - I used a mix of 34 x 44mm and 44 x 44mm for mine. Straightforward to attach to the underside of the baseboards and you can add horizontal stiffeners where necessary... Yours, Mike.

For controlling my MP1 motors, I use the Digikeijs DR4018, as mention above by Iain Morrison - that is indeed a cost effective solution if you're using DCC. The DR4018 has 8 channels for turnout motor control and a single channel can drive multiple turnout motors in situations where 2 (or more) turnouts need switching at the same time, such as crossovers, since the MP1s only take 150mA. I've not used the MP1s in an analog setting, so I can't comment on that, although the feed to the MP1 motors is an analog 12V, as you mention. I think that the following video shows an analog arrangement using DPDT switches, if I have understood it correctly: Meanwhile, it is also possible to control mimic LEDs (for feedback) for the MP1 using the arrangement demonstrated in the following video: Yours, Mike.

James, I can't agree with your comments about turnout motors, at least as it applies to my experience using MTB MP1 motors. First, the MP1 footprint is quite small, 28 x 40 x 13mm, with the longest dimension along the direction of the track, so that the motor sits underneath the turnout it is operating. I have had no problems installing MP1s in "crowded" situations including 3-way points, double junctions, double slips, etc. The MP1s have a further virtue in allowing for a good deal of adjustment, particularly perpendicular to the track direction. Second, MP1s don't draw any current when they are idle - they cut out when they reach their end position. Indeed, if they don't cut out, this indicates a problem such as an obstruction preventing them reaching their end position, which I find a useful characteristic since the small buzz they emit brings my attention to the issue. And yet, despite having the cut-out, the MP1 design still means that the turnout blades are fimly held in place at the end position. A further advantage of MP1s is that they have a built-in micro-switch that can be used for controlling power to the frog of the turnout. Regarding wiring, I use 17A / 2.5mm2 stranded wiring for my main bus and 10A / 1.0mm2 stranded wiring for my accessory bus and I don't find them "impractically thick" - they are very easy to work with. I use 0.75mm2 and 0.5mm2 stranded wires for connections from the bus to accessories and track and they too are easy and practical - for example, connecting straightforwardly to the screw clamps on both MP1s and the Digikeijs DR4018 units. I think that protection against short circuits is advisable whatever the wiring used - but larger wiring itself is actually a protection against fire once the wire can handle more current than the power supply can deliver - it is undersized wires that can overheat and burn.

Wordsmith, First, regarding the wire types. I use stranded wire everywhere - even for dropper wires. I find that solid core wires are much more difficult to handle, especially when soldering, so I never use them. I generally use wires from mains flex (flex, not mains cables!) for larger size wires, since they are readily available and relatively cheap and are colour coded. Flex wires are available from 2.5mm2 down to 0.5mm2, with nominal current carrying capacity over distance (i.e. in terms of metres) as follows: 28/0.3 == 14 AWG == 2.5mm2 17A 19/0.3 == 16 AWG == 1.5mm2 13A 32/0.2 == 17 AWG == 1.0mm2 10A 24/0.2 == 18 AWG == 0.75mm2 6A 16/0.2 == 20 AWG == 0.5mm2 3A I have used the 3 alternative formulations for describing the wires here - this is a very confusing topic. I prefer the cross sectional area formulation since it does not depend on the wire construction, unlike the stranding formulation. I use 2.5mm2 wire for the power bus - more to keep the voltage drop low across my layout, since I doubt I'll ever be using 17A! I use 1.0mm2 wire for my accessory bus. Connections from the bus to units like the Digikeijs DR4018 for point motor control are typically done with 0.75mm2 wire while connections to my slow-action point motors (MTB MP1s) are in 3 strand 0.5mm2 flex. Dropper wires, typically no more than 200mm long, are done with black stranded wire 0.25mm2. Regarding your power supplies, I was surprised to see you mention a 10A supply. You must be using some very power hungry accessories to need that, although such supplies are readily available from the world of laptops and similar equipment. I run my layout using a 3A supply for the controller and a 2A supply for the accessories. Yours, Mike.

Bob, Congratulations on a superb and very professional set of videos. Mike.

Regarding "Tap Splice Connectors" (as RS Components dub them), otherwise called Scotchloks after one of the leading brands, I have very good experience with them. There are different sizes of connector - and the right size must be used for the wires concerned. My DCC power bus uses 2.5mm2 flex cores (== 14AWG) and I use the Blue RS Components connectors to tap into the power bus with 0.75mm2 (== 18AWG) wires. These tap wires I typically then connect to a pair of terminal connectors which then have two or more pairs of dropper wires attached - the dropper wires are smaller still, to make the connections on the track unobtrusive. The terminal connectors allow me to detach the droppers if required. Meanwhile the DCC accessory bus uses 1.0mm2 flex cores and I use the Red RS Components connectors to tap into this, linking to 0.75mm2 or 0.5mm2 wires to whatever accessory device is involved, such as the Digikeijs DR4018. Using the tap splice connectors is quick - stick the relevant wires into the connector and a quick squeeze with a pair of pliers and it's done. I've never had one fail on me. The bright colours used are also helpful in finding the connections when messing around in the dim light under the board. The tap splice connectors are really cheap - a recent 50 pack of the red connectors was £1.65. Yours, Mike.