Portable Progress

Portable Progress

12th November 2009

Behind the scenes preparatory work regarding the two portable engines recently purchased by the museum continues. Prior to going to tender for their restoration, a full survey of each engine’s condition has to be prepared and compiled into a set of tendering documents and the beginnings of a Conservation Management Plan. This informs and guides the restoration and subsequent use and management of the engine and is something we produce for all such work. Those for Coffee Pot and Lewin run to tens of thousands of words!
All known information on the history is also recorded, as well as what is discovered. It informs the scope and extent of work carried out (balanced against the pragmatic need for safety and operational requirements) and so produces a detailed record of the engine/artifact. The value of these to curators and conservators cannot be understated!

For the portables, we contracted Vince Allen to remove the tubes, then Graham Morris to carry out a detailed boiler survey of each engine. This has been recorded in the CMP as well as enabling the tendering document to be created. This is a detailed 8 page review of the condition as currently understood, an inventory of each aspect of the engine and a detailed set of requirements regarding the restoration. Backed by an inspection by potential contractors, it should enable a realistic appraisal of the cost and scale of the work to be produced.

Below: The Clayton & Shuttleworth portable (13818/1874) – this view shows the girder stays on the firebox as well as the longitudinal stays above. The findings of Graham’s inspection reveal that a new inner firebox will be required (it has been boiled dry at some point during it’s South American life and as a result has ‘quilted’. This term reflects the fire-side appearance, where the stays have held steady but the plate around them has bulged, so creating the appearance of a quilt. There also appears to be a very bad repair made at some point and no fusible plug!!! The lack of the latter may explain the former of course…

Below: An internal view of the Clayton’s boiler, looking from the smokebox end. Note the four longitudinal stays. This boiler is wrought iron – according to Clayton’s catalogue for the period, it is ‘best Low Moor iron’. The barrel and outer wrapper are reusable, likewise the backhead. The front tubeplate will require renewal however. Some of the tubes removed were interesting in themselves, being welded together from several pieces of varying section pipe!

Below: A view taken from the Clayton & Shuttleworth catalogue, showing a very similar portable engine. Our forecarriage is missing and will require replication – fortunately an identical one is preserved in the Museum of English Rural Life at Reading and can be copied.

Below: The Ruston, Proctor has also been surveyed and a CMP/report produced. The engraving below shows how it will look, the main difference being that it has a longer firebox (for wood burning – the lower calorific content requiring a larger surface area to produce the heat). Our Ruston also had a brake, as shown in the engraving – not a common feature on portables.

Both portables will now await developments but hopefully we will be able to make some progress next year…

Below: A Rack-saw has recently been obtained from Brandon (and it was originally installed near Brandon colliery on Sawmills Lane) and this has been brought, in pieces, to our store. It will be cleaned, conserved and prepared for eventual reassembly in a steam powered sawmill (driven by the Ruston – seen in the background!) at Beamish. It has been undercover all of its life and we are currently looking into its origins and true age.