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Model train repair shop

MPB Model Supplies carry out Hornby train repairs, as well as model locomotive repairs to other brands, and DCC conversions.

Current repairs

We are working to finish existing repairs in the run up to Christmas

New Premises

While these current repairs are being completed we will not be able to accept additional repairs until we have found new premises

Please fill in this form to be notified of a free repair slot in early 2024

Our workshop has a booking system with a maximum of 30 repair slots at any one time.

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Our workshop offers the following services in OO9, OO, and O Gauge Railway sizes:

  • Servicing of locomotives and rolling stock
  • Replacement of broken parts where new (or second hand) parts are available
  • Fitting of DCC Decoder Chips
  • Converting of analogue models to DCC
  • Programming of DCC Locomotive Addresses
  • Customisation with working lights, smoke, sound
We are unable to repair Clockwork or live steam locomotives

If you are wondering whether it is worth repairing your locomotive then our article Are model trains worth anything? could be helpful

How much will a model train engine repair cost me?

  • Full Service and clean £35
  • Replacement motor from £55 including a full service
  • Replacement contacts/pickups including a full service £55
  • Complete rebuild including motor, pickups, motion and service from £90

How much will model railway dcc fitting cost me?

  • DCC Fittting to a new locomotive including the decoder £55
  • DCC Sound Fittting to a new locomotive including the decoder £175
  • DCC conversion of older locomotives including a full service £75
  • DCC Sound fitting to 8 pin dcc or non dcc locomotive all inclusive £225
  • Additional DCC Features not already in your model
    • Directional lighting £45
    • Firebox flicker £30
    • Seuthe smoke (does not produce synchronised chuffs) £55
    • ESU syncronised smoke (O gauge and larger scales only) from £105 (requires suitable decoder)

Full repair service including Mechanical and Electrical repairs

Locomotives are particularly sensitive to dust and the mechanisms and motors can pick this up. Carbon brushes are also prone to wear on older-style motors, and power pickups can corrode over time. All these things can be put right with careful servicing.

It is advisable to have locomotives that have been in storage for any length of time serviced before first use.

A quick servicing check list would be:
  • Carefully remove any visible dust with a soft brus
  • Check for slight movement forwards and backwards in the wheels by hand, in a locomotive with coupling rods some movement is expected.
  • Check wheel centres for signs of cracking or movement on the axle
  • Lubricate any dry moving parts with appropriate plastic safe oil
  • Try the locomotive gently on its own, the motor should not get hot
  • If the locomotive runs ok add rolling stock gradually.
Picture of old hornby chassis
Picture of old hornby loco

Common problems

  • Perished traction tyres
  • Worn or missing motor brushes
  • Bent pickups
  • Poor tender to loco connections on tender drive locomotives
  • Bent coupling rods or valve gear
  • Life expired suppression capacitors
  • Dirty wheels
  • Broken or missing detail parts
  • Axles on split chassis model trains are a well-known failure point.

Replacement model train parts

Within the first 12 months of ownership, it is best to return your models for repair or replacement under warranty.

Outside the first 12 months we can repair model and garden railway items using replacement parts where available, or, we can try to repair the original parts providing we have all the bits.

With some models it is possible to replace older worn out parts with newer equivalents.

New brushes for motors cost a few pounds, to import a motor from America for a Bachmann USA model recently cost £35.

Fitting of DCC Decoder Chips

Any digital model railway control system requires a special control chip or 'decoder' for each locomotive, rolling stock, or accessory to be controlled digitally.

DCC stands for Digital Command and Control and is the universal standard for digital control adopted by multiple manufacturers.

The system works by broadcasting encoded control messages uniquely addressed to individual decoders drawing power from the digital controller.

Adding DCC decoders to a DCC ready locomotive

These are items where the manufacturers have designed the models to work with analogue DC controllers or with digital controllers when a decoder is fitted.

It is a case of fitting the model with a decoder that uses a matching connector, either 6-pin, 8-pin, next18, or 21-pin. Some models like the Bachmann double fairlies come with the speaker fitted, others will also require a speaker to be installed for DCC Sound.

On locomotives with lighting fitted most models will have enhanced lighting control under DCC Control.

We fit decoders to analogue locomotives and rolling stock

These models require more work involving re-wiring and possibly alterations to the body or internal construction in order to connect the decoder and physically secure it in the model

None DCC ready locomotives tend to be older locomotives which brings the added challenge of converting engines which are often worn and tired.

It is impossible to convert split chassis designs without completely rebuilding the locomotive with major modifications.

Picture of dcc loco


Picture of bachmann double fairlie dcc loco

DCC Sound fitting for locomotives and rolling stock

There are three major components that have to be right for the best possible sound:
  1. A high quality sound decoder
  2. Speakers
  3. The correct sound files

We recommend and fit the ESU Loksound range of decoders, they have a long established track record and a range of sizes and power ratings

Using cheap speakers will give poor results, you need a speaker that can handle a wide frequency range with an air tight speaker enclosure for enhanced bass.

Wherever possible sound files recorded from real prototypes should be used. The decoders use high quality digital recordings to reproduce the sound of the locomotives in action. Each class of locomotive has a unique sound profile. Some sound files available use poor quality recordings or simulated sounds.

Programming of DCC Loco Addresses

By default new DCC decoders come with the default address of 3. This means that you select locomotive number 3. With multiple locomotives you need to assign unique numbers to them to control them individually. We offer a programming service where we can set the address for you while you wait.

Customisation with working lights, smoke, sound

It is possible to add extra details such as working locomotive lamps, flickering firebox effects, smoke units and carriage lighting to your models.

Please contact us for a quote

Flickering firebox

This involves making small cuts around the firebox doors to let the glow filter around the edges, or, removal of the fire doors to simulate the firebox doors in the open position.

ESU decoders have a 'firebox flicker' function that varies the firebox lighting dependent on the loco performance for a more realistic effect


Illuminated miniature locomotive and train lamps are permanently attached to your model and can be fitted to both analogue and DCC controlled locomotives


The most common OO Gauge retro-fit smoke generators are made by Seuthe, and they perform best in DCC fitted locomotives where they can be provided with the optimum voltage.

Seuthe smoke generators have a small heating element that vaporises the smoke fluid. Getting the precise amount of oil is crucial or they wont create the smoke effect.

On larger scales, fan-assisted smoke generators can be used to synchronise exhaust chuffs to puffs of smoke