by John Rodway

As with any method of ballasting, first make sure the track is thoroughly tested and proved to be reliable. There is nothing so depressing to operators as track that is beautifully ballasted, but technically flawed. The testing procedure I use is based on one developed by my father and his brothers over 70 years ago.

• Look along the track from just above rail level to ensure that there are no dog’s legs or undulations.
• Repeat, looking back towards yourself using a mirror resting on the baseboard at arm’s length.
• Run 4-wheel tank locos at ultra-low speed to check for stalling. Poor electrical continuity would indicate undulations in rail level, perhaps caused by incorrectly inserted rail-joiners or rail-fixings.
• Run the longest tender locos and bogie coaches to check clearances, especially on curves where trains pass platforms, bridge abutments and each other. Also run locos of 4-4-0 and 0-4-4 wheel arrangements as they are particularly prone to overhang on curves.
• Run locos at speed in both directions, and turning the locos round to repeat the process, to check that curves on the track are smooth.
• Propel rakes of coaches and wagons to check that they flow smoothly through curves without buffer-locking.
• Propel long trains at speed through point-work to check that it is up to standard.
• Run as full a service as available stock will allow to ensure that both the track plan and the quality of its construction are fit for purpose.
• Try moves not envisioned at the planning stage. Visiting operators are particularly prone to do this. It will highlight operational problems that need to be sorted out while it is still relatively easy to make changes to the track plan or rectify poor track-laying.
  

Spreading the ballast

Run dry ballast along the track so that it forms a low ridge between the rails. Use a finger, a scraper or a brush to spread it out along the ‘four-foot’ until it is just below the top of the rails. Don’t worry too much if there are ‘thin patches’. These will often sort themselves out. Those that don’t can be spot-treated later.

Using the handle of a screwdriver or similar blunt object, lightly tap along the top of the rails. This will fluidise the ballast. As if by magic, the bouncing ballast will flow under the rails and around the ends of the sleepers to form the shoulder. If the result isn’t to your liking, then use a brush, or a palette knife, or a wall-paper scraper to push the ballast back over the rails ready for another fluidisation attempt, or to scrape excess away from the track.

Fixing the ballast

When the ballast is in place, mist it with water. A small modified medical pumpaction nasal atomiser is excellent for this (friends with allergies may be able to provide these). The feed tube is cut at the internal base of the nozzle, or pulled off completely. This allows water to enter the atomiser when upside down. Spray can be more accurately released from a couple of inches over the track than from other dispensers such as greenhouse sprays and air-fresheners with large reservoirs. Even this close, the spray droplets will just drift down onto the loose ballast and anchor it without disturbance.

As has been reported many, many times, the addition of a small amount of surfactant to the water (e.g. soap, detergent) will help the water penetrate the ballast more easily. If the ballast is deep, then a second application of mist may be helpful. Leave for a few minutes for full infiltration. Well before the mist has dried, gently run a 50:50 PVA/water mix down the centre of the track. (Again with a trace of surfactant!) Try not to let it flood over the rails so as to minimise the need for subsequent cleaning of the running surface The solution will pond up between the rails, percolate to down to the baseboard and then migrate outwards into the shoulder. Because the ballast has already been wetted, it is unusual for any ballast to float. Once it has dried, apply further diluted glue until the ballast is firmly fixed. It is best if the baseboard can be left horizontal until the glue has fully set. Subsequent inversion or brushing will remove any unstuck grains.

And finally…

As is normal practice, care and suitable precautions have to be taken around pointblades so that they and any electrical contacts do not become contaminated with glue or ballast grains. Using this method, several yards of plain track can be treated during one modelling session. Indeed, because of the waiting time for the penetration of the mist and the drying of the first application of fixative, the process positively encourages long lengths of track to be tackled at one time. It can become addictively more-ish. Two bits of advice. Avoid prolonged tapping on club layouts if other members are trying to have serious conversations. Even more important, don’t tap on loft layouts when your wife is downstairs. She’ll quickly enlighten you as to the drawback of this method of ballasting. It’s best done when she’s out.