4mm Holt (ex-Delph) - A P4 layout under construction

Dave Holt

Western Thunderer
With my loco construction (currently rebuilt Royal Scot 46109) having run out of steam for the moment, I thought I might post something about my P4 layout. Actually, I'm not sure this should be here as the section is called "Layout Progress) and the layout hasn't made any progress for some years - awaiting conversion of the garage into a model railway room. Despite this reservation, I'll plough on.

The layout has its origins in a house move. My first intention had been a continuous oval depicting Knighton, on the Central Wales line and a full sized track plan was created by cutting paper templates for the point work. However, a house move resulted in much less space. Some time later, I bought a book about the Delph Donkey (by Michael & Peter Fox), my interest being prompted by my mother having travelled on it for a brief period during the Second World War when she was an agency short hand typist at a dye works in Delph. A photo of an Ivatt Class 2 2-6-2 tank departing the station, propelling two aged push-pull coaches, particularly piqued my interest.

The book also contained a track plan (dating back to the 1880's. I found that a shortened version of the station and yard area could be accommodated on a layout across the diagonal of the spare bedroom, using a kick-back arrangement for the fiddle yard. A small scale track plan and general layout arrangement was developed, including cross sections at various places along the layout - the station/yard area are cut into a hillside with a road and river at lower levels to the front. Quite nice natural framing. However, before construction could commence, a further house move resulted in the need for a further evaluation.

In the new house, the second bedroom was smaller and the proposed layout wouldn't fit. However, a de-mountable layout, in sections, could be occasionally erected in the through lounge/diner and sun lounge extension. Indeed, such an arrangement would allow a dead scale model of the station/yard area, without the need for any compression. Over the years, various books, articles and track plans, including a large rating plan, had been acquired and contact made with someone who had been involved in another model of Delph and had useful information. A friend from the Scalefour Society kindly offered to create the scale track plan in Templot by overlaying a scan of the rating plan. This file was subsequently imported into a CAD file, allowing some scenic features and baseboard arrangement to be added. The resultant layout plan is shown below.
Track layout0070.JPG
The idea was to have the main boards extend to just behind the mill siding with light weight hang-on scenic boards to carry the scenery behind the track.

Although the track layout, up to the yard throat, is a scale model of Delph. the scenic feature at the left, to disguise the exit to the cassette fiddle yard and the configuration of the the mill behind the siding are not prototypical so the layout name was changed to "Holt". The long bridge (short tunnel?) and the cottages in the roughly triangular area at the left are on the Delph branch, but further along towards the junction with the main line, being located at Dobcross (Dob Cross?). The mill was intended to be a late period (1904), red brick, replacement for the actual, rather gloomy stone built mill which was behind the station (now demolished, I believe). In recent times, I've veered back towards the prototypical mill, so the name change might not be required, now, but the station and signal box already carry the Holt name, so I'll stick with it. Anyway, by not being Delph I can vary the train services and stock beyond the limited variety that actually ran there.

So far, the main boards are complete (but not the fiddle yard or scenic boards), track laid, ballasted and wired up. The Station platform and building, the goods shed and the signal box were all made for me by Peter Leyland. Here are a couple of shots of the layout, not necessarily in its current state, to give some idea of the overall arrangement.
That's friend, David Clarke, scraping paint off the rail heads prior to a running session.


Dave Holt

Western Thunderer
The intention was always to build the layout to be taken to exhibitions so the scenic part was broken into four reasonably manageable sections, The location of the joints was determined by the track layout and some scenic features. It was not possible to arrange for nice symmetrical boards which could be bolted back-to-back for transport, as many exhibition layouts are, and the four sections vary greatly in length and width. Transport was intended to utilise a multi-level, wheeled trolley, which would accommodate the maximum length and width of the various sections. With the passage of time and lack of completion, etc., it seems very unlikely that the layout will ever attend any exhibitions, but at least the sections can be stored and moved about at home reasonably easily.

No legs are provided as the idea was to have a separate support structure which would be erected and levelled up before sitting the layout boards on top. This structure has not been made (yet?) and recent ideas replace the original wooden construction with one made from rectangular and square hollow section steel.

The boards are made from a marine grade of MDF (nothing like the stuff you find in B&Q) with a 12 mm top, in the area where the track is, and 6 mm ribs forming the support framework and front scenic extension. Large lightening holes in the ribs both reduce weight and allow wiring to pass through. The end plates are laminated from two 6 mm layers with a thickness of card between. The need for the card was to allow the female halves of the locating pattern makers dowels to sit slightly below the outer surface. Although the end boards are flat, they are not necessarily square to the back edge of the boards and the joint in the top surface is kinked or stepped, to suit the track layout, at two joints.

All the board construction (and track laying) was done at a friend's workshop in Leamington Spa with much help from the friend. He isn't a modeller, but has a lot of experience with using this type of material. Here are some views of the boards under construction. Sorry for the poor quality, but these have been enlarged from some rather small original files.

The tops laid out (outside) to show the overall spine of the layout.
Delph boards 02.JPG

Boards under construction showing the lighted support ribs. In these shots, two boards are connected together.
Delph boards 05.JPG
Delph boards 06.JPG

Delph boards 08.JPG
In the last shot, the staggered joint in the top can just about be seen. This was done to keep the joints more or less square to the track and to avoid some point-work. The recess at the front is where the coal drops are.

Once the main spine was completed, the scenic sections in front were grafted on.
Road way dropping down from the station towards the coal drops.
Delph boards 15.JPG

The transported Dobcross scenic break.
Delph boards 17.JPG


Western Thunderer
Good to see the layout is back on your agenda Dave. I used to wonder where a Bulleid Pacific and Royal Scot fitted into the scheme, but I know you just like building engines that turn you on.

I always hoped the fireman would go sick on the Delph Pilot turn when I worked at Lees! It also included other duties and was a Fairburn 2-6-4T turn in 1960. The other Fairburn wasn't needed until the evening for Clegg Street parcels. An Austerity would have been interesting on the Delph branch curves!

Dave Holt

Western Thunderer
As you say, Larry, some of my locos are not related to the layout but are just types I like. At some huge stretch, the Scot could appear on a Wakes Special, especially since it's Holt, not Delph.
In all the information I've accumulated, there is very little about freight train operation and I have not been able to find any photographs of the Delph goods actually on the branch or at Delph itself. Not even Jim D seems to have taken any.
According to the Lees loco diagram sheets, the Delph pick-up goods fell into the Motor link in the 1950s. I'm not sure if this implies that it was worked by one of the motor fitted 2-6-2 tanks or if it was just the crew was from the link and any suitable loco would be used? One would imagine that a Lanky A class would be more appropriate.
In my version, a WD is more than a possibility. In fact, with small wheels, close together, the fixed wheelbase id not much different from the standard MR wheelbase used on the Fowler 2-6-2 tanks, so the curves on the branch would not have been too big a problem. WDs were certainly used on other single line branches in the area.
PS. 16'-6" fixed wheelbase for the 2-6-2 tank and 16'-3" for the WD.
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Dave Holt

Western Thunderer
Having explained some background to the layout and covered the assembly of the base boards, the next topic is track.
The track plan was done using Templot and all the point work made using rivetted ply sleepers. This was all done for me by Tony Wilkins, a recognised expert in P4 point construction. The plain track, except for a few short lengths of rivetted construction, was plastic based, flexible track from C&L. All the moulded sleeper ties were removed and the sleeper spacing adjusted to suit track panel ends and LNWR spacing for short panels in the yard area. In this, I assumed the running line would have been relayed in 60 foot panels, whereas the loop and yard would remain in 30 foot lengths.
The point work was delivered by Tony, temporarily attached to hardboard sheets, as a mixture of individual points and larger assemblies, as shown below.
Throat track-work.JPG

Here's the same unit of point work (plus a bit extra) laid but not fixed in position on the baseboard.

The area where track would be laid was covered in 3 mm thick cork, reinforced at the board joints by 3 mm thick wood strips, as seen here at a later stage of construction.
These shots also clearly illustrate the staggered board joints mentioned in a previous post. Also seen are the rivetted ply sleepers used to provide a more substantial rail fixing than the plastic sleepers at the board joints.
My original plan was to glue down the Templot plan to the cork and lay the track on top of the plan. I've seen this done on other layouts shown on the net, but I found the paper templates wrinkled and could not be kept flat so, instead, I marked the track positions onto the cork using pins and ink dots. These marks were then joined up with marker pen to shoe the rail positions, as also seen in the photos above.
The point work was then positioned over the marks and carefully adjusted for alignment, etc., and its location defined by inserting pins into the cork at sleeper and point assembly ends.
The unit of point work could then be carefully lifted out, PVA glue applied, the point replaced and weights placed whilst the glue set. I found that there was a very slight mismatch in height between the rivetted points and the plastic based plain track, so paper strips were fixed under the lower part adjacent to the joint, before fixing the track.
Once the points were fixed down, the linking sections of plain track were prepared and a smooth alignment checked by sighting along before pin marking and track laying using the same method as the points.