Richard Cleaver
Photos by the author

THE ARTICLE News of the Moos by Chris Gwilliam, which was published in the November 2020 Gazette, caught my eye as I too have recently been bought a Parkside PS107 kit for the Southern Cattle Wagon, as a present. Like Chris, I choose to spring wagon wheels on my Parkside models but I use a different form of suspension as I have got rather fed up of hunting for small coil springs that fly off my workbench. I think that my arrangement might be of interest to the Gazette readership.

The springing arrangement is simplicity itself and involves drilling two holes and inserting a piece of wire that has been formed into an S shape. My method for carrying out the installation in each W-iron is as follows and is shown in the explanatory photograph. The first task is to draw out the spring shape on graph paper, as shown.

The dimensions have been selected to hide the metal behind the cast plastic spring so that the arrangement is not visible when viewed from the front. I use phosphor bronze wire for the spring, carefully bent with fine pliers using the drawing as a template.

On the basis of several models completed have found that 28 SWG (0.376mm or approximately 0.015in.) wire provides a good result. I have tried thinner (30 SWG) wire, which didn’t possess enough strength; and I found that 0.5mm wire (25 SWG) is too stiff. I should declare here that my wagons are constructed to have a weight of approximately 100g per axle which requires either a load or a small amount of supplementary ballast. I assume that stiffer springing would work if the wagons were heavier but that is an area that I haven’t explored; a subject for the Guild Technical wizards, perhaps.

It helps to drill the holes in the plastic components when they are still on the sprue and I find that a 0.4mm drill in an Archimedes drill or pin holder works well. One hole is drilled in the top of the W-iron and one in the top of the bearing carrier. The holes need to be about 10mm apart so that the spring is not in compression when the bearing is at its lowest point in the W-iron. The shape of the spring can be adjusted to suit the dimension if this is more or less than 10mm.

Having assembled the W-iron with its moving bearing assembly, the ends of the spring are inserted in the holes and secured with superglue.

And that’s it. With this arrangement, the sprung W-irons keep all four wheels in contact with the rail head, even over the dodgiest of permanent way.