Waton - N gauge challenge

[StevieDay]

When wired up, wont the current short circuit from 1 rail to the other via the coppercladding?
Or is copper cladding not copper? As in nickel-silver rail has no silver in it & is actually copper-nickel rail.

That's what the insulating gaps are for, each sleeper has a gap cut in the copper cladding (a few strokes with a file). It gets a bit tricky in the middle as there may be more than two bits of rail on a sleeper. If you need an extra gap after assembly it's the cutting disk in the "Dremel" and a light touch as youonly want to remove copper not plastic.

Thanks for the explanation Bufferstop.

[ElDavo]

The wrecking crew have been at it so there is no going back now!



There was definitely something I was going to do before lifting the existing track. What was it? Oh yes, test the crossings. Oops.

Cheers
Dave

[DonB]

Good to see some updates on this wonderful layout ("train set" is certainly the wrong word for this masterpiece of N Gaugery, and does your skills as a modeller a great disservice IMO).
56018 looks marvellous, both clean and weathered. (Anyone who knows me as a modeller will know of my opinions on weathering; i.e. do it right or not at all, and '018 looks perfect.)

I am from an engineering background (albeit electronics!), and the crossing looks OK to me.
That said, scratchbuilt track in 4mm gives me a headache, let alone 2mm...

As long as it works, that's the main thing.
There is some pretty shocking trackwork in my fiddleyard, if one looks closely enough...

I hope to see Waton in the flesh someday. Any plans to exhibit the layout in the Midlands, the Nottingham or Derby shows?

[ElDavo]

... I hope to see Waton in the flesh someday. Any plans to exhibit the layout in the Midlands, the Nottingham or Derby shows?

Thanks for the compliments Don. As you point out, in the fiddleyard it doesn't have to be pretty, just work.

The only booking I have in the Midlands currently is the Warley show at the NEC in 2014.

Cheers
Dave

[ElDavo]

Surprise surprise when I came to test the crossing complex there was a short! Not at all surprised I have to say. It took me a day or two of head scratching before I spotted it but I found it eventually. Having ripped up all the old track there was nothing for it but to stick the new crossing down and sort out the approach tracks.

All four approaches and four exits have now been laid and wired in. Not a pretty sight.




Amazing how much internal wiring was hidden on those Atlas crossings. There are also a bunch of wires in place as I don't want to rely on fishplates for electrical continuity. The radii are better than they were but not quite as large as I would have liked. A couple of multiple units, a Farrish 170 and a Dapol Voyager, that wouldn't negotiate the old curves will manage these so they are probably good enough.







There are still no check rails on most of the crossing but things seem to run reasonably well. More fettling to do then the acid test, will the full HST rake propel through it at a scale 90mph.

Cheers
Dave

[ElDavo]

Been a while since anything was posted here and as Waton is due out at Uckfield next month it's time for some activity. During the original challenge only one of the required signals got built due to time constraints. Time to sort that out.

The first signal was built using surface mount LEDs and was a bit of a pain to say the least. Need to find a better and more reliable method.

The MkII signal heads are being built in a slightly different manner. First up a baseplate of clear perspex is cut and the LEDs are stuck face down into a layer of quick set epoxy. Here's a 4 aspect with a feather under construction...



With the LEDs nice and secure they are wired up using enamelled copper wire. A pretty tricky operation given the size of the things!



Good idea to test everything at this stage. Of course forgetting to use a resistor and blowing the LEDs would be a really stupid thing to do...

All being well the wires are reinforced by adding another layer of epoxy. In the pic below a 4 aspect head is at stage one alongside. Double sided tape helps...



Slow going but progress none the less.

Cheers
Dave

[ElDavo]

Bit more messing around today. Another 4 aspect head wired up after much rework. Soldering these tiny LEDs is seriously tedious. This and the one with a feather will be mounted on a gantry at the western end of the platform controlling westbound movements from the platform and goods relief road.

Having wired the heads and reinforced things with copious quantities of epoxy it's time to look at the front. Bits of brass tube have been cut and filed to produce lamp hoods. They aren't strictly to scale but have been super glued to the front side of the perspex base. I decided hoods for the 5 feather lamps was going a step too far so currently I just have a bit of brass strip with holes.

These will need testing then a coat or two of paint then it will be time to see how they look on the gantry...



Cheers
Dave

[luckymucklebackit]

Nice work with the signals there, cannot imagine what it must be like to work in "N", as I am building some 00 gantries and they are small enough for my hands and eyesight!!

Jim

[ElDavo]

Further work on signals sees 2 MkII signal heads fitted to the gantry destined for the west end of the platform. They seem to have survived painting and fitting and amazingly all the aspects still work! There is a bit of a problem with light bleed through but I may have to live with that. Onwards to MkIII.



Cheers
Dave

[ElDavo]

Not done much on the signals themselves today but been playing with this sophisticated test rig. Maybe not immediately obvious what it's all about...



Obviously it's a bit of Peco N gauge track balanced on a bit of 5mm ply. The interesting bits are actually underneath...



There are a couple of resistors connected to an Arduino processor board but the really interesting bit is an infrared proximity detector, actually a TCRT5000L. It's the thing with 2 bits of brass tube stuck on the top. These have been added so it can be mounted under the baseboard without detecting the board but is able to sense things through a couple of small holes.

So what is all this palaver all about you may ask. The obvious way to control colour light signals would be with a few switches but that is just too simple. I want the signals on Waton to switch to red automatically as the train passes and to reflect the state of the next signal down the line when they are cleared. Bit tricky to do with simple switches.

The infrared detector will be mounted under the track beyond the signal and will allow the Arduino board to sense that the train has passed the signal. In addition the state of the next signal down the line will be sensed so when the signalman pulls the signal lever it will change from red to green, yellow or double yellow as appropriate. That's the plan anyway.

This actually only needs a relatively simple processor so the Arduino Mega 2560 with 52 inputs is a bit of an overkill. What I will actually use is an Arduino Nano which is a lot smaller...



Lots to do.

Cheers
Dave

[ElDavo]

The westbound gantry has now had a ladder and safety hoops added and planted on the layout. Of course this means dismantling half the set up but...



Not much is to scale but it doesn't look too bad.

Work is underway beneath the board as well so holes have been drilled for the infrared sensors...



Cheers
Dave

[ElDavo]

With the signals installed above the board it's been wiring time. Not everyone's cup of tea I know but some of like the challenge!

The enamelled copper wires form the signal head emerge from the bottom of the gantry upright and have been terminated on a scrap of salvaged tag strip. Each of the signal heads has a current limiting resistor in the 0 volt line...



A pair of infrared detectors have been glued into holes excavated in the baseboard and wired back to the vero board with the Arduino mounted on it...



Ribbon cables run from the Arduino outputs to the signal head tag board and switch inputs run back to the off board connector.



Amazingly this lot seems to work! There was a serious face palm moment when I realised I had wired the LEDs of the detectors to the 12volt supply rather than the 5volt supply from the Arduino. Not surprisingly this destroyed the LEDs. Luckily I had spares.

The light bleed in the signal heads means I'm not happy with the yellow aspects so currently I have it set up only to use the red and green. Lots more to do...

Cheers
Dave

[ElDavo]

Those fed up with twaddle about signals should change thread now! A MkIII 4 aspect head is under construction. This one has the LEDs mounted on a bit of plasticard with holes albeit still using epoxy.



After wiring up the back is liberally smothered in epoxy as per the previous version...



The light bleed looks to be better so far but we shall have to wait and see. Currently I'm waiting for the glue on the brass tube light cowls to harden so everything can be painted.



A second Arduino board has been prepped ready to drive this and another signal head. These are on a different baseboard to the previous gantry. Testing of the gantry signals has removed a couple of unplanned features (bugs) in the software. The signals now nicely pop back to red once a train passes over the relevant infrared detector.

I have also added a lunchtime/lazy Sunday afternoon feature. If a train passes the signal it returns to red but if the signalman does not put the lever back in the frame within 20 or so seconds the signal will again clear to green ready for the next train. This means a lazy operator can set up a route and run a series of trains only having to select the required train in the fiddleyard.

Next up is to fit two more infrared detectors and adjust the wiring in the control panel. Hopefully once I've done that the missing circuit board header sockets I need to complete the second Arduino installation will have arrived courtesy of the postie and I can wrap it all up.

Cheers
Dave

[THE CHIEF]

Wow! Thats amazing Im looking at signals myself and found this thread. Now thats how its done The filter is fantastic. Most of the signals ive looked at are good but these blow them away. The wiring is annoyingly neat too Bookmarked this thread and shall continue to watch this one. Many thanks.

[engineer dave]

Hi

Amazing layout. All that hand - laid track - you must have some patience! Incredible stuff.

I love the signal lights too.

All teh best

Dave