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6 inch scale Clayton undertype steam wagon - stock code 12982

A 6 inch scale Clayton undertype steam wagon, based on the popular 2 inch scale design, published in "Model Engineer" magazine. We bought this one from its builder in 2002; a man with wide-ranging interests, he'd also built a 7 1/4 inch gauge Bagnall and a full-sized steam narrow boat.

It was campaigned regularly for four years after completion, including many of the local rallies around Oxfordshire and several visits to the Great Dorset Steam Fair.

We tested the commercially built boiler at the time and steamed the wagon, remarking on its speed - it would certainly get you to the beer tent quicker than a 6 inch agricultural and, with pneumatic tyres, in considerably more comfort!

It was last steamed in 2002 when its new owner collected the wagon from our old premises in Woolhampton. It's never been fired since, garaged in company with a venerable Fowler road locomotive and a vintage Rolls Royce open tourer. Too many toys, never enough time - it's a problem we know well...

Since the wagon arrived back with us we've given it a preliminary hydraulic test, the boiler showing no signs of leaks or distortion, followed by firing it so that we could have a play in the yard!

The engine itself runs well, the boiler steams freely. Steering is heavy, not helped by lack of top support to the steering column.

The mechanical pump proved reliable, the injector isn't - we suspect it needs a bigger clack valve.

The water gauge is - like all Claytons built to the 2 inch scale model design - set far too high on the boiler. In the 2 inch scale model it's understandable (if still wrong) as the water gauge has to be above the cab floor (when much of the boiler, iceberg-like, lies below it).

The open footplate of the six inch engine gives scope to fit a longer water gauge, with the bottom fitting set closer to the bottom tubeplate. Currently if there's water showing in the gauge, there's virtually no steam space, witnessed by a steady light shower of water from the chimney.

A worthwhile project for those wanting a large engine for little more than the price of a fairly pedestrian 3 inch scale agricultural. The boiler will need lifting for a cladding off inspection and hydraulic test before certification can be issued - it would be a good time to fit the extra water gauge bush.


length/inches 97
width/inches 41
height/inches 60
weight/kg 538
wheel material pneumatic
axlebox type plain bearing
cylinder material cast iron
valve type slide
valve gear Allen straight link
reverser type pole
injector(s) 1
boiler number FB258
year built 1998
boiler maker Franklin & Bell
CE mark n/a - pre-2002
boiler type vertical
boiler material steel
boiler construction all welded
steam test valid to FALSE
superheater(s) 0
fusible plug no
safety valve(s) 1
safety valve type spring
mechanical pump 1
whistle yes
road speed(s) 1
differential yes