I visited the London Festival of Model Railways held at the Alexandra Palace on Sunday 30th March and among the many fine layouts on show one in particular took my fancy. This was Sandford and Banwell, an oval Great Western line featuring a junction and modelled in P4. See these links for some pictures of the layout

https://www.flickr.com/photos/richardjslipper/sets/72157651653968411/ http://www.scalefour.org/scaleforum/2014/sandfordandbanwell/

One aspect of this model was the use of plastic drainpipes for the supporting legs and to support the fascia for the over-layout lighting. Light in weight the builders had used solvent weld waste pipes with cross struts. The tops of the legs were pushed into wood blocks and the bottom had adjustable feet held in blanking plugs. All very neat. Over on RMweb others have also commented favourably on the arrangement. Being at a critical juncture in the baseboard build for TheRSR, where I need to consider legs my encounter with the drainpipes on S&B was rather timely. Thus I have been investigating the products and materials. But it ‘ain’t so simple as it first appears.

Most builders/plumbers merchants sell solvent weld waste pipes in a variety of sizes, 32mm and 40mm being the most common, with 50mm also available. I decided to trial the 40mm pipe and duly arrived at Wickes with a mental list of the parts I needed. Notwithstanding the fact that they had very poor stocks of the fittings I discovered that the 40mm pipe they advertised was actually marked by the manufacturer as 43mm. To cut a long story short 40mm is the inside diameter and 43mm (nominal) is the outside diameter. In fact it’s all a bit approximate but provided a single product range is used this shouldn’t be a problem.

But a problem does arise when boring a hole in a block of wood for the leg to sit inside. It needs to be snug, not to tight but clearly not loose. While 40mm flat wood bits and 40mm hole cutters are reasonably easily obtained, 43mm ones are less common and may need to be sourced on line. Of course the 32mm inside diameter pipe will have an overall diameter of between 35 and 36mm both sizes also being less common. The answer to the challenge would seem to be an adjustable bit. Screwfix do one which allows holes between 22mm and 76mm to be made.

The cost of the pipes for the legs is probably less than new wood would cost, although the cost of a special bit does increase the spend. The weight saving would be considerable.

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