Cast in Sand

 Something that has been exercising our minds and the pattern makers arm muscles for some time is the fuel pump and governor unit. The blog entries for 10th& 16th February 2020 describe the inner workings of this unit and that of 17th October 2021 summarises progress on making the pattern for the governor housing and the fuel filter. 

Both these patterns have now been completed by Bob Smith & Adam Livingston. Bob trained as a pattern maker straight out of school and is now retired. He described it as the most complex item he has ever worked on. The main pattern and some of the coreboxes are illustrated below, together with the body of the similar, but smaller casting from the MDB2 engine, which has been used as a point of reference.

Given the complexity of the beast Bob & Adam tried their hands as moulders, to ensure the cores can be removed from the core boxes and that the necessary clearances can be achieved to produce the wall thicknesses required. An interesting exercise, which also proved in part that their skills lie elsewhere; being a moulder is a skill in its own right.

The chaps at Cerdic Foundry in Chard fortunately have all the skills required to turn wood into sand and ultimately into iron and another of the big hurdles for the project has now been cleared. If you turn to p26 illustration 6 of your McLaren spare parts catalogue you will of course recognize components 532 (Fuel Pump Gearbox) and 540 (end cover for fuel pump gear box).
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Those who may have mislaid this useful reference will find the illustration from the catalogue in the 10th February 2020 blog entry, which has a painful reminder of how many small and intricate parts now need to be manufactured.

One photo hardly does justice to the massive amount of work that has gone into recreating this extremely complex component so here are a couple more views to allow it to be appreciated.

The fuel filter body is small and relatively simple by comparison. If you have the KS4415 Panini stickers book this is part number 852. The pattern and role of this component was described in the 17th October 2021 blog. Rather less daunting to complete, it is another useful work in progress milestone that has been passed.

Progress! Progress!

 

It may be eleven months since the last blog entry, but progress over the last couple of months, since the end of the train playing season, is extremely encouraging. Some of the ‘slow burner’ projects which have required research, draughting and in many cases pattern making suddenly have tangible progress with components being delivered from outside contractors. When this paid-for progress occurs concurrently with the steady grind of the volunteer group on restoration tasks the advances made since the end of the train playing season are significant. From a restoration perspective, the fact that we are working on some quite large part that is relatively simple may suggest that things are moving on less quickly than they feel, says the pessimist.

The elephant that is not in the room is the engine block, which is still with specialist contractor Formhalls, another contractor we have used with specialist skills and no concept of programme. Putting a positive spin on their lack of progress, instead of plodding on with a diligent, engineering-led one nut and bolt at a time restoration we have made the erratic decision to go for a ‘fur coat and no knickers’ approach to restoring the body ahead of the engine. Even more mad (and something we try to avoid) is the use of ‘a deadline’. You have no doubt read it somewhere else first, but our intention is for KS4415 to make a side show appearance at the WHR centenary event, to be staged on the 23rd- 25th June 2023.

The appearance of the grit blasted components is encouraging and we will be able to re-use a lot of original material:

One of the angles used to attach the body sides to the top wrapper was found to pretty good. Rob Bishop grafted on a short section of new steel to the foot and it is fit for re-use (see below)

The condition of the cab-end brace is not so good and it will require replacement:

The lower body panels also require replacement and the sheet of steel required to make these in one piece needed a special two-bogie delivery to the guillotine:.

In addition to the two, new lower body panels there is enough steel in this sheet to provide the components required to repair/ replace the cab sides (as required).

Although the steel  order was large, we did not order the required holes. Scott Todd-Howard is seen cracking on with a boring (so droll!) task. The original bodyside (painted red oxide) has been bolted to the restored angle section. The lap plates (on the inside of the body, which cannot be seen here) have also been bolted on and the new (bare metal) panel is being drilled with holes for the rivets. There is an angle along the bottom of the new sheet which attaches the body to the chassis. This was too wasted for recovery and has been replaced:

 This photo shows the completed bodyside, with a new door temporarily put in place (the original was removed long ago in Mauritius).  The new lower angle can be seen, together with the small patch replacement near the seam to the left hand original panel:

One of those curious things that you never notice until you get down and dirty with this stuff is that the upper body panel of the loco, when built was formed of a single sheet of steel. Why is there a very neat, riveted, vertical joint in it now? There is an angle stiffener just to the left of join, which can be seen in this photo at California works:

Both sides are now at a similar stage of (in)completion. The other (drivers side) panel requires the angle frame to be replaced. Some holes and the worst areas of waste have been replaced in this panel (touched up with grey primer on the photo below).