New layout: All in a day's work - part two

Prior to today's hectic all-day session, the turntable has been cut out so that it will line up properly with the track (the Marklin turntable is much deeper than the standard Dublo one)

Hole cut, turntable test-fitted.

All six boards were then primed and painted prior to today's session, here they are assembled again for the first time since they were made and checked to ensure minimal warpage and of course that the dowel pins and catches still line up. 

It's a snug fit but everything works.

Once a good fit was confirmed it was time to separate the front & rear sections ready to fit the electrical connectors.

After fitting the front section first, the rear boards were flipped and the breakout PCBs that I had shipped over from America were cut into position. A nervous moment as a lot of money has been invested in these components with the intention of minimising the amount of manually connected terminal blocks, which the previous layout had many of. These weren't really intended for this kind of use, normally you would plug a 37 pin cable into the socket, not a PCB into a PCB. The theory here is that once the dowel pins have been lined up, these will connect together when the boards are then clipped together.

And it appears to work! - Each section was tested, separated and re-joined and each board connected properly with no fuss.

As time began to defeat us, there sadly wasn't much time to wire up or fit track. We did however manage to fit a perspex protection panel along the front edge of all three front boards (it's hard to see it in this picture but it's there along the top) after loose-laying all the track along the front three boards, I managed to mark and drill the holes for the wires to the two pairs of points and fix down most of the track on the first board.

Just a few more pieces of straight and the corners to fit, then this board can be wired. End panels have also been fabricated and bolt to the exposed board edges so that the track is fully protected for transportation, also means that the boards can easily be stacked.

Good progress again after another long day, still need to lay track, wire up and then start thinking about scenery, then there's the upper loop to be added but this can't be done until the hills & scenery are done. All agreed that if work slips behind and the deadline is at risk then the top loop will be put on hold.

Fingers crossed we can still meet the deadline in October.

New layout: Wiring

I seem to be forever soldering.

Every spare evening is spent in the back room armed with a soldering iron. Thankfully the control panel is now completely finished, apart from two coats of varnish to protect the new paint.

Time to concentrate on the wiring for the track. As there are six individual boards I will need to ensure that all the tracks are electrically connected via the 37 pin connectors.

I also need to wire the points motors and modifiy the existing Dublo wiring under the points to allow for track isolation (Dublo never made isolating electric points sadly)

For the wiring I've opted for six core alarm cable - this stuff is stranded wire rather than the solid cores found in telephone cable. I used phone cable throughout the old layout and found that it didn't like being used in terminal blocks, didn't solder that well and became quite fragile. I'm also conscious of voltage drop through the extensive amount of wiring being used on this layout, alarm cable doesn't tend to suffer too badly in this area, let's face it, it's designed for 12v use and on a standard house alarm system you'll find miles of this stuff in between all the sensors - if it works for that then it'll work for this... that's the logic anyway.

Here I've cut lengths of cable ready to solder to the points...

Once all the points were wired, I labelled them (as some have a different configuration and some don't require isolation) and then soldered individual wires to some straight track sections to allow for all the board joints and the eight isolated sections in the main station...

Another tick off the large to-do list, just the back boards to do now!

Turntable test

First test of the newly "modified" Dublo / Marklin turntable using the new switch panel and control PCB...

New layout: Control panel completed

Possibly the most labour-intensive project I have ever undertaken!

The MDF casing needed priming before paint...

I found a reasonable colour match for the blue, I wasn't going to go all-out and get the colours professionally matched, no point and this, for a cheap shop own-brand paint, does the job quite nicely. While the paint was still drying I loosely fitted the main panel for the first time... 

Next day, and after the paint had hardened, I began wiring the Duette controllers into the panel (should call it a Quartette now I suppose)

40 LEDs had to be soldered and glued into position - hours of work involved in this and when I finished, the light was way too powerful as this picture demonstrates...

After a bit of head-scratching, the problem was resolved by adding two more resistors in the 0v return.

The 37 pin breakout PCB was wired, plug-in terminal blocks have been used so that the panel can be removed easily for maintenance. 

Everything in position... finally!

There were problems - many of them.

First of all, two of the brand new switches were faulty, thanks to my wiring diagram and schematic diagram I was able to trace and rectify the problem with relative ease. Just annoying that new switches should fail like this.

Then I discovered problems with the Duette controllers. First of all, two of them, when energised, operated at full power on minimum and minimal power on maximum. After more head-scratching the problem was traced and resolved, two wires on the potentiometer reversed!

After resolving that issue, another Duette problem. If controller B was used in forward and controller C in reverse (the two main loops) a short circuit was detected by the ammeters. This one took a fair bit of tracing, taking a whole evening alone to resolve.

Finally the fault was traced to the centre of the potentiometer for controller B. Basically the centre shaft (the bit that the control knob attaches to) is live at +12v dc. On the Duette, this is insulated from the body of the controller by using a cardboard spacer and a large, square cut-out which ensures that the shaft can never come into contact with the controller body. Although I'd re-used the cardboard spacer, I'd drilled a round hole only slightly larger than the diameter of the shaft itself, and this rubbed the centre shaft. After a quick re-drill of all four controllers I refitted & tested. Job done!

Having all of the major components on plug-in terminals made the process of fault-finding much simpler so already this decision has paid off.

A much more sensible brightness level. Just need to secure the main panel and, once varnished, the job is done.

I'm now in the process of testing the PCBs I made for the boards. So far I've tested the eight relay track isolator and the first, two capacitor PCB for board one, just need to test the turntable control - already confirmed that there's power from the panel to the PCB but as it's getting late I'll test tomorrow. The turntable is a tad loud to be testing at this late hour.

Although it's taken many hours just to build a switch panel, I think the end result is stunning - far better than I could ever have hoped. I particularly love the new panel for the four Duette controllers. The printed & lacquered vinyl looks amazing, albeit still with some small air bubbles. It was annoying that I couldn't use the same process successfully on the main panel but this, for now, will do.

Next weekend we'll hopefully commence track laying and wiring.

New layout: Control panel - inside a Duette

I was always intrigued as to what was inside the A3 and the H&M Duette controllers. At least one of these mysteries is now solved.

After drilling out the rivets, the lid lifts off. I've already removed the left hand controller by this stage.

The rivets holding the rectifier and cut-out for the left hand controller have also been drilled out ready for removal.

A 16V AC twin coil transformer sits in the middle, supplying independant power to each controller.

The 16V AC auxillary output is simply connected straight to the standard output of the transformer coil, after the cut-out device, with the other 12V DC supply tapped from the rectifier.

The auxillary outputs are not required so wiring is slightly simpler. 

The components are stripped, the potentiometers are mounted to the new panel and new, colour coded wiring used to make it easier for me to identify which wires go where. New toggle switches replace the old H&M ones for resistance and half wave.

All that's left is a shell, two outputs and a bank of switches.

After stripping the second Duette, all four controllers are mounted to the new panel.

And the cut-outs & rectifiers mounted to a spare piece of aluminium left over from the control panel.

This is now ready to drop into the new control panel, I'll use pluggable terminal blocks here so that if a fault occurs, I can remove either the control panel or the transformer and rectifier assembly easily without the need to de-solder anything first.

New Layout: Electrics

My evenings seem to be taken up with soldering, lots of soldering.

First PCB to be constructed is for the first board, this comprises capacitor discharge for two points, track isolation for the two points (as Dublo points aren't electrically isolated) and turntable control - the relay & diodes of which were reclaimed from the small control PCB that I built ages ago for the turntable.

After many more nights of soldering and making lots of mistakes (ie having the layout map upside down) I've finished all the PCBs for the layout.

This little lot needs to be fitted throughout the front three boards...

The shuttle control is still in its bag and the signal matrix control was purchased a few years ago. The rest is self-built.

The eight relay bank is for the track isolation controls within the four tracks of the station. Elaborate but allows easy connection and disconnection of locos & multiple units etc.

I have to confess that the smaller, two capacitor PCB on the left was actually the first PCB that I produced for board one but sadly I didn't buy bread board large enough to accommodate the second bank of terminal connectors and the large capacitors. For board three there are only two pairs of points and track isolation is not needed so I de-soldered the second bank of terminal blocks and soldered in the capacitors. In reality I probably could have produced a completely new PCB from scratch quicker than it's taken me to re-hash this one but I don't like seeing things go to waste!

I've tested everything as far as possible using my multi-meter to ensure that there are no dry joints, so far so good. Now to test the capacitors using a pair of points.

The idea of using home-made PCBs is that this should make wiring the boards much simpler. On the old layout, the switches were mounted in the boards with individual wires and capacitors all over the place. One stray wire could take ages to locate. This makes the whole process a lot simpler and should (hopefully) make fault detection much easier, plus I have circuit diagrams to refer back to - previously I've done everything by memory, the result being that each board ended up being wired differently with different colour combinations used for the points wiring. Everything across this layout will be standardised.

Much easier.

New layout: Control panel progress

The control panel is making slow, steady progress.

The lower panel is still waiting for the rest of the components to be swapped from the two Duette controllers. Some drilling of rivets and rewiring required first.

I mocked up the display, printing the design onto ordinary A4 paper, the idea being that I could then mark out the positions of all the points switches and LEDs, rather than trying to drill through a freshly lacquered panel and risk ruining the final finish.

The left panel has been redesigned as I wasn't happy with the look.

Mocked-up and refitted to see how it looks...

Time to mark out the holes, I centre-punched these in an attempt to stop the drill from moving when I cut the holes. Once all the holes were punched, I removed the template...

After lots of drilling (pilot holes, followed by 3mm LED holes and 6mm switch holes) I ended up with what looks more like a pin cushion. The ammeters were also cut in using a series of drilled holes and a reamer.

It's fair to say that using 2mm aluminium sheeting was way over the top for this, 1mm would have done the job. Drilling aluminium creates lots of swarf, which needs to be removed from both sides or it'll ruin the final look. I found that the easiest method to remove the excess metal was to carefully re-drill each hole with a larger diameter drill bit. After all the drilling, filing and reaming, I ended up with this...

The original plan was to finish this panel in exactly the same way as the transformer panel, however there are problems with the method I used - basically printing onto glossy vinyl and lacquering in place. The vinyl isn't too happy with the inkjet printer, the ink doesn't fully dry and smudges with ease - even if left for a few days.

I tried several times to print and stick the vinyl overlays into position but found it impossible to do this without creating air bubbles underneath, I can't apply any pressure as this smudges the ink! - I've experimented with applying a thin layer of lacquer prior to application, this worked reasonably well but I've now run out of vinyl. Not to be beaten, I've printed all of the control panel again onto photo paper and have experimented with using PVA glue to stick the panels to the aluminium, once dried I'll apply several coats of lacquer which should eventually give me the same look as the bottom panel. This has also proved troublesome and for now I'll have to wait for the glue to dry to see if this was a good idea or not.

New layout: All in a day's work

After a 10 hour stint today, we've made progress.

Two more of the old boards are now stripped of their track, taking the total to three.

All six boards were brought together today for final assembly, tweaking, dowel pins and boarding.

The frames were clamped together ready to mark up for the dowel pins. Ideally this should be done on a bench using a pillar drill. We chose this method A) because the ends of the boards had already been glued & screwed and B) I don't have a pillar drill. After careful marking and drilling, the dowel pins were glued and tapped home. 

Once the dowel pins were in position, time to fit the toggle catches to each side, these ensure that the boards stay tightly clamped together. Final checking of the front boards before fitting the top MDF panels to ensure everything is straight & true.

The front and rear sections all locked together for the first time, some minor tweaking required on one corner, apart from that, everything is square.

Time to add the top layer of MDF, everything checked again for the best fit before adding glue & panel pins.

Looking along what will be the front of the layout - a lovely blank canvas.

16ft x 5ft of three rail porn!

With everything nailed & glued, time to start loose-laying track for the best fit, taking into consideration the location of points to ensure they're not fitted over board joins and trying to get most of the track joins near the edges to avoid excessive track cutting. 

Strange to think that when the portable layout was first built, at this point we would have screwed down the track and then run it in this state with bare MDF. Not this time, this time there will be paint, scenery, ballast and hills!

Trying to find the best fit for the turntable - after so many hours went into modifying this it would be a great shame not to use it. This will need to be recessed into the timber due to the height difference.

Deviating from the original design I drew on SCARM, the shuttle track in the foreground was initially designed as a small village terminus and wasn't intended to be used as an independant shuttle line. It was to be linked into the main track here and into the run round loop but as this now runs into the main station, there is no need for additional points here. I have a plan for the shuttle control to also work the points and alternate the shuttle service between the two platforms. More designing & testing required first to ensure that it'll work before I commit this to the layout.

A tunnel is planned for the two running loops here, it will commence just after the end of the turntable.

The TPO moves to the mainline, on the old layout this was situated in the station and its use limited to one platform. Placing it here makes it more accessible. Also gives the three front boards something of interest on each board. This centre board will also comprise the four road level crossing. Some debate as to whether this needs repainting to match the station platforms.

I had a plan to add sidings behind the TPO, hence the points at the back of the level crossing, I got out-voted on this so this will be replaced with a half curve.

The level crossing will also need to be slightly recessed, as we discovered when it was used on the previous layout. The main station will be situated here between the crossing and the tunnel mouths and will be exactly as it is on the previous layout, using three platforms. Now that the TPO has moved, I can extend the platform further along.

The tunnel mouths have been cut and will require joining & repainting. There will be a proper tunnel with scenery here and the pointwork beyond will be just inside the tunnel.

The design here is similar to the current layout but with some redesigning to incorporate the shuttle track, which will be on the left of this picture, running from the points along to the far right hand side of the layout.

I intend to keep the same track isolation plan as I had on the previous layout - each of the four tracks will have two isolated sections. The shuttle will run into the first section where a diode wired underneath will stop the train running further into the station area. I will fit an override switch so that I can run to and from the shuttle station as normal if I wish to, and take the empties back to the depot at the end of the day.

Tunnel will be here, with another tunnel at the other end. Scenery and a raised loop to be added later.

Looking from left to right along the front, there will be a lot going on, way more than the current layout. The trackwork I've tried to deviate from long, straight sections to create some interest, whilst not complicating things to the point where derailments & uncouplings will occur.

The high edge of the board has now been trimmed to a better size, it slops back up to this height near the tunnel entrance and perspex will be added along the front to protect the layout and discourage wandering fingers when on public display.

I can now go away and design the mapping for the control panel now that I know where all the points are and how many are needed. The track has now all been removed as the boards will require primer & paint, then I can start planning the wiring and fit the board connectors. The PCBs for the points controls also needs to be constructed.

A very, very long day but we've achieved a great deal here.

As a final note, I take no credit for any of the carpentry skills seen here. I merely supplied the hardware, my brother is responsible for the construction of this and many hours have been spent producing these boards so the standard seen here. My job was to fit the catches & dowel pins, lay the track and wire the thing up!

No, we don't do commisions! 

New layout: Progress 26/3/14

The first of the old boards has been scrapped.

Now you see it...

Now you don't...

It is sad to be scrapping these old boards, I haven't yet decided the fate of the entire old layout but I do need to reclaim most of the track and this particular board, being oversized and wont even fit through the loft hatch, has no real future purpose. The timber from the sides of the old boards will be recycled to use as supporting legs for the new layout - no more resting on tables and hopefully no more back ache!

The scrap, non-working, spares-or-repairs Duette controller arrived. After checking it over with the multi meter to ensure it was safe to run, I connected it to the mains and found that everything works - A bargain, fully functioning Duette ready for stripping!

As for the switch panel, work is progressing well.

The final design was printed onto self-adhesive, glossy photo paper. I chose photo quality paper as this will take the lacquer coat better than normal paper - my experience with the coach overlay kits was that applying lacquer over the transfers created blotchy marks. The only unfortunate problem is that whilst the yellow background dried perfectly, the blue linings and lettering have embossed over the top of the yellow ink, meaning that they haven't been saturated by the photo paper and tended to smudge, this has led to some air bubbles being trapped under the paper as I couldn't apply much pressure when attaching the stickers.

This is basically two pieces of A4 paper, cut into the two sections and joined in the centre, which is then carefully stuck to the aluminium panel...

I've stripped out the potentiometers from one of the Duettes, marked, drilled and reamed the new panel to fit and replaced the old H & M switches with toggle switches - these are easier to mount and have a better feel than the old switches.

I'm really pleased with the final appearance, just need to remove everything and lacquer the panel...

The switch panel casing has been built for me - my carpentry skills weren't up to this. This is constructed from spare 6mm MDF left over from the construction of the new boards. I chose a home-made panel after many hours of research concluded that a factory built panel of this size was far too expensive. This one so far has been built for around £25.00 including the aluminium sheets.

I couldn't resist test-fitting the new panels, it fits like a glove!

The top panel will feature some switches and two digital ammeters on the left side and a map of the front three boards on the right, with all the points switches drilled into the panel. I also intend to fit LEDs to indicate the position of the points. Using the learnings from making the bottom panel, I will make a low-resolution black and white stick-on template, drill and file all the holes then remove the sticker, clean, file and de-grease the aluminium panel and then apply the final stickers. This reduces the risk of damaging the stickers when drilling and I want this to look perfect. I may also apply one coat of lacquer to the stickers before I apply them to the aluminium, hopefully this will reduce the risk of smudging the ink and will allow me to use more pressure to remove any air bubbles.

When finally finished, the box will be painted blue. I found a good resolution picture of a Dublo loco box and was able to get a good colour match from it, I'll print a high-resolution sample and get the paint mixed at a DIY store. A little anal maybe but it's all in the detail!!!

I have now received all of the capacitors, relays and breakout PCBs that I need to construct the layout. Next stages are to commence making the PCBs and fit the dowel pins and catches to the boards, before priming, painting and then commencing track laying. Then there's scenery and the raised loop...

Lots of work done and many hours spent so far but way, way more to do...

New layout: Designing the control panel

Rather than having switches on every board (like the current layout) I want a central control panel. It was a long-term goal with the old layout do do away with the individual switches - they get knocked and damaged so a central control panel is the way to go. I also want a panel with the controllers built in - no more wiring up each time etc.

I had hoped to go over to Gaugemaster controllers but as I need four of them, this won't be cheap and funds are already tight.

I love the feel of the gaugemaster controllers, however I also like the feel of the old H & M Duette - especially the centre off position. As I already own a Duette I figured that I may as well look to incorporate this into the design and find a second unit, which I've now done. I've sourced a broken Duette from Ebay which I'll repair and use in the control panel.

I want to build the controllers fully into my control panel and not just squeeze the entire unit into the panel. Having taken my existing Duette apart it looks like a reasonable task to strip it from its existing enclosure and make something "bespoke."

I scanned the fascia panel into my computer, after a lot of tweaking with the brightness and contrast, I ended up with this:

Not brilliant, the right hand side of the fascia is bent & discoloured, also there are lots of scratches. Certainly not good enough to construct a new panel.

Time for some airbrushing!

I want a panel that looks uniform in appearance and not just look like two Duettes thrown together.
The scan of the old fascia, although tatty, was good enough in places. The dial markings and the lettering around the switch banks scanned perfectly. The rest of the lettering I re-did.

After much airbrushing, scratch removal and touching-up, I ended up with draft 1:

The right hand dial was too badly marked to re-use, so the left hand one was copied and used for all four dials, giving a more uniform appearance. 

Not bad, I think it looks far better than the original panel and far more bespoke. I don't intend to re-use the existing Duette switches, I'll substitute these for toggle switches.

I decided that the panel looked a bit bland, it really needs some colour and I guess it's only fair to include the H & M logo.

After some more tweaks, I have what I think will be the final version:

I think this will look good, the combination of yellow & blue suits the Dublo style. I've ordered some aluminium sheets which will become the control panel, this will be printed onto sticky-backed photo quality paper and then lacquered once in place. A second sheet of aluminium will become the signal & points control panel, which I can't really design until the tracks are laid and I know exactly where all the points will be.

More to come...