DMU Update (M56484), Spring '25

We are pleased to share several recent photographs demonstrating the progress we have made with the restoration of our Class 108 Diesel Multiple Unit. Wherever possible is included a similar photograph taken earlier in the restoration.

The above photographs show the progress on the cab front of our Trailer Car M56484.

Colour Scheme

The DMU had arrived at NPL Thornton in March 2020 and by October 2020 the paintwork had been rubbed down to reveal traces of the yellow whiskers applied back in 1960.

Over the last few years the metal work has been primed, received two coats of green undercoat and a single coat of gloss green. A second coat of gloss green will be applied during 2025 and eventually we intend to reapply the yellow whiskers.

The roof of M56484 has been painted in grey (again primer / undercoat and gloss) plus the moulded fibreglass cab roof has been repaired and made waterproof.

All the fittings have been removed from the buffer beam (in both pictures), and these have been overhauled and repainted ready for refitting. The buffer beam itself has had red oxide primer applied and will receive its gloss red once the main body work painting is complete.

Various Works

This winter we spent many hours replacing all the window rubbers and the February 2025 photograph shows the recently installed window rubbers on the cab front windows.

All the electric circuits have been tested on the carriage and the headlights successfully tested.

The destination box situated at the top of the centre window has been restored and revarnished back to the original mahogany colour.

Unfortunately, we do not have a set of the original destination roller blinds to put in the box, but have fitted a dummy "Preston" destination board.

The above two photographs also show the progress made over the same period, October 2020 to Feb 2025.

Some early restoration work on the underframe is captured in the 2020 photograph whilst the more recent photograph shows how smart the underframe now looks.

The brake shoes (blocks) on M56484 are badly worn and we have acquired a set of brake blocks from the Dean Forest DMU Group. These will be fitted this year.

The bodysides and the roof have gone through the same painting process as described on the cab front photographs. The more recent photograph shows the bodyside after the window rubbers work was completed.

Eventually lining will be applied along the sides and carriage number and the British Railways coat of arms transfers applied.

Both our carriages are on short lengths of track and every now and again we turn the wheels to prevent the bearings seizing up. Surprisingly, this is quite an easy task just requiring a few volunteers using crow bars to turn the wheels, plus of course others with chock blocks to prevent it running off the rails.

In an ideal situation, both carriages would be coupled together; end to end, but due to constraints on our site they had to be placed side by side.

The design of the DMU provides for the complete train to be controlled from either cab. In order to test the main power circuits, our electricians have connected the two carriages together with long umbilical cables which allowed them to successfully run through the engine controls from both cabs.

Another task for this year is to replace the life expired and leaking vacuum brake pipes, so that we can test the vacuum brakes work.

Carriage Heaters

Heating for the trailer carriage is provided by a heater slung underneath the frames.

This is known as a Smith's Carriage Heater and it runs on diesel fuel from a small fuel tank also attached to the underframe.

There is a similar heater under the power car.

Neither of our heaters were in a working condition with several damaged or missing parts.

Fortunately, we have skilled members who have completely rebuilt both the heaters and successfully started them up.

The heaters probably last worked properly way back in the early 1990s.

Now work is underway to refit the Smith's Carriage Heater back under M56484.

Door Restoration

In the 1960s it was common for British Railways to use wood trim around doors and windows and the modern-day use of plastic was still some way off.

Unfortunately, sixty years of service has seen a marked deterioration in the door trims, and virtually all are needing replacing.

Clive Pickup is our resident carpenter, and he is currently busy making new door cards and top panels for the doors in M56484.

In the 1960s British Railways used mahogany for door trims, but this is no longer readily available, and even if you can source any new or any recycled wood, then it is extremely expensive.

We are now using sapele which comes from more sustainable sources.

Each card has a sapele frame around a plywood board.

Once the panel has been made it will then have a layer of mahogany veneer attached which will then be varnished.

Although all the carriage doors appear to be of a standard design, we have found that each door is slightly different, and that each door card or panel must be individually fitted by planing the wood to fit each door.

Once fitted each panel is individually numbered and can only be used on that door.

Other Work Planned for 2025

We have noticed that some of the metalwork below the corridor connection needs rewelding and to do this we need to completely remove the corridor connection.

In fact, we have just started dismantling the corridor connection to gain access to the complete rear of the carriage to carry out the necessary welding along with some painting.

Watch out for the next of this Spring 2025 update. This will cover the restoration work carried out to date on our Power Car M51937.

Nigel Kirkpatrick