Abercadabra (N/N6.5 gauge)

[ian]

More than a little while ago I was building an OO/009 exhibition layout called Aberlaff (see elsewhere in the forum) which got culled long before completion.

 

Now, as Minffordd has hit a similar problem - the allocated space has disappeared - I started to think "What DO I have space for?" (or rather, "For what DO I have space?").

 

The answer is either one 3' x 2' board or a pair stored face to face.

Now 3'x2' isn't a great canvas to work with but 6'x2' is a possibility - especially if it is fattened up to 6'x 2'3". Aberllaff had (in OO) ended up at 12'x 2'6" which was the absolute maximum that I could get into the car. It had been slimmed down to almost anorexic levels to get to that width. So shrink the plan to N and Bob is, if not a parental sibling, certainly a close friend of the family - with extra width available to boot.

 

Still narrow gauge in N isn't exactly off the shelf. It usually involves Z gauge track and mechanisms at 6.5mm gauge to represent 3' gauge prototypes. Most North Wales narrow gauge was somewhere around 2'. But fret not - 3' gauge lines were (albeit short-lived) to be found at Pwllheli, Portmadoc, Barmouth Junction, Penmaenmawr and LLechwedd (plus one in Pembrokshire and another in Llanelli) - so reality can be plausibly stretched.

 

So take an oval of Z gauge track and a cheap mechanism, some N gauge track and an even cheaper train for comparison and what do you get?

 

I was brought up with the Festiniog as the essence of narrow gauge railway. Whilst it was main line in attitude it has to be admitted that the actual stock was, shall we say, on the diddy side. Now 3' gauge railways tended to be somewhat chunkier, not far off standard gauge light railway size.

 

This is fortunate because when you take a Z gauge coach chassis it is pretty much the same size as the inside of a N gauge coach. The smaller running gear does give a lower overall height helping with a more narrow gaugey feel.

 

I still need to add step boards by the doors, paint it, glaze it, replace the roof moulding with something a bit thinner and decide on couplings but it has potential.

 

Of course if you really want 3' gauge around these parts you need to head westward to the Isle of Man or Ireland. I have always had a soft spot for the West Clare's Walker diesels.

 

So this was sort of inevitable...

 

I'd forgotten just how fiddly smaII scale soldered track is. 6.5mm gauge is even more so!

 

 

A full-size plan was printed out to see how it goes together.

 

Some quick placeholder buildings were knocked up for effect. The DMU is standing by the BR platform. Behind the DMU a road rises to the left. At the bottom of the hill is the bus garage, Dai the Death's premises and a garage where the road turns to go over a level crossing. This is a one way street with traffic running left to right.

 

On this side of the level crossing the road splits to a two-way road climbing a hill on the right and another one way street which runs past the BR station and then climbs to the left.

 

The narrow gauge station is at a lower level, and the beach lower still (about sea level in fact).

 

Here the DMU is on the bridge over the narrow gauge and about to enter a tunnel. The road climbs steeply and an RAC van is attending to a car that gave up the struggle. The snaking blue line is the backscene.

 

Looking back the other way you can see the backscene crosses the standard gauge near the end of the terraced houses and then runs along the back of the shops.

 

After much jiggery pokery the plan ended up at 72" x 20" on two 36" x 20" boards.

The railway line that looks like a railway line is the narrow gauge. The crimsony one is the standard gauge.

 

The weird roads are a Faller Car System circuit for the buses (dark grey) and Magnorail for cars (light grey). Rather than a continuous stream it will be one on each circuit.

 

I intend to put in animation of various sorts and as a result am contemplating calling it Abercadabra.

 

Which gets us to here:

 

[Keith Addenbrooke]

Incroyable!
 

 

[St Enodoc]

Looks like you're cooking with gas! A bit disappointed you haven't got a flat crossing for the two lines...

[SimonHMT]

Looks like this is going to be quite something! 

I've built one layout in N and dabbled in N-6.5/Nm...in fact, somewhere in store there's a (very) small box of kits, chassis and parts for some locos and rolling stock to go on a diorama I built a while back that fits in a wooden box that held a bottle of wine. 

It's nice to see someone building a proper layout. 

Will watch with interest, 

Simon. 

[ian]

12 hours ago, St Enodoc said:

 A bit disappointed you haven't got a flat crossing for the two lines...

I did look long and hard at the WHR/Cambrian crossing but the interaction of two railways and the road would be an operational bottleneck and require a larger baseboard to compensate for the loss of the narrow gauge level and the requirement to get the off scene curves around the standard gauge.

 

37 minutes ago, SimonHMT said:

Looks like this is going to be quite something! 

I've built one layout in N and dabbled in N-6.5/Nm...in fact, somewhere in store there's a (very) small box of kits, chassis and parts for some locos and rolling stock to go on a diorama I built a while back that fits in a wooden box that held a bottle of wine. 

It's nice to see someone building a proper layout. 

Will watch with interest, 

Simon. 

Yes, N6.5 is one of those rarely trodden paths. Already I can see why!

[ian]

Meanwhile I have been mithering an Arduino to persuade it to take up layout control duties. Firstly it is being trained to be a controller....

 

The upper sections of roadbed have been removed from the layout so that I could glue down the plan for the narrow gauge. Now I know where to cut the slots for the point mechanisms.

[ian]

More messing with the Arduino.

 

It has gained an LCD screen to impart useful operation to the operator - although with the backlight on you can't see what it says on a photo - it is fine in reality.

 

I have also added a small board to run a point servo.

 

Now, given that an Arduino can operate a servo with one arm tied behind its back, standing on one leg whilst humming the national anthem why go to the trouble of an extra board? Using the arduino's in built ability for servos requires you to either wait until the servo finishes moving before continuing on to other things or do some tedious coding. This way it can just tell the board that the servo needs to move and let the board do the donkey work. It also has the advantage that the servo leads from the layout to the control panel could get quite long - anything upto five feet and in an electrically noisy environment like a model railway this can lead to unwanted twitching (from the operator as well as the servo). The servo board can go close to the servo and the electrical interference is minimised. (The board is a MERG kit, available to members only - https://www.merg.org.uk/content/kits)

[ian]

Not dead, just sleeping!

 

I have given up on the handlaid 6.5mm gauge track. My bastardised track gauges were not great and faffing around with devices to operate the points was taking far too much time and effort so, I have taken the easy option and used Märklin points and sectional track plus Peco flexible track for the main runs.

A 9V battery provides the oomph for testing purposes. By way of a bonus it also flips the point motors as well. That will save builidng a CDU.

[ian]

The head of steel has moved on through half of the hidden sidings.

In a change to the earlier plan there is now a loop for clockwise running, a loop for anti-clockwise running and a stub end track at either end for adding and removing trains.

There is still a way to go until the golden spike!

[ian]

The narrow gauge track has all been laid and the various dropper wires connected to longer lengths of wire. Initial testing was by the simple means of placing a 9V PP3 battery across the track and watching the locomotive take off like a scalded cat.

 

Even in scalded cat mode the test train retained all its tail load. This isn't an action shot - I couldn't hold the battery and the camera at the same time!

 

The controller is supplying 16V AC for the high-frequency track cleaner (the black box on the right). Experimentation confirms my suspicions that it is a necessity for this layout.

 

The stub end sidings in the hidden section are for adding and removing trains. The two loops can hold two trains each - one pair going clockwise, the other anti-clockwise.

 

The large Marklin mechanisms have been cut away from the points in the scenic section.

 

Servos have been installed under each of them.

 

[ian]

WIth the NG track all laid and functioning attention has turned to the upper levels. First of all the section of NG along the river valley had to be painted and ballasted as it would be difficult to access when the upper level board went in.

The standard gauge shares the town level with the road vehicles and getting the location of the level crossing is the key to positioning everything.

 

Looking from above the standard gauge tunnel on the left the road crosses  the river and narrow gauge before the road splits for the one way system around the town. In the middle the standard gauge crosses the river and NG before it meets the level crossing. The narrow gauge meanders alongside thr river. To the right, hidden behind the backscene are the hidden NG tracks and roads.