I make this post just as a series of observations which may (or may not) be usful to some brethren.
A while back I was trying to pick brains to determine the difference between un & rebuilt pacifics (both types) but without result. i had acquired a r/b MN chassis without proper valve gear. later i aquired a new unr/b WC body (Blackmore Vale). The chassis fitted the body so I bought the cyls & valve gear for that model and all fitted nicely. The only problem was the contraints placed upon the trailing pony truck by the rather garish ejector & other drain pipes so I cut them off a repositioned them and applied a little weathering. The was also a strange fret under the coupling position of the loco which I removed. Voilà, one nice and tidy West Country. The tender is a composite of the modern chassis and an unpainted original Hornby shell which is the same size and does fit after removing the lower moulding in the coal chute ( I reversed the drop in "coal" to make it bottom up so that real coal could be subbed.)
At about the same time one which I had bought new arrived so i was able to make the comparisons.
First problem = lack of adhesion. Second = Faibless of the valve gear, particularely the slide gear.
The faults were common to both.
The first I cured by adding 60 grms of brass strip to the interior body cavity of both . This needed to central above the front & centre driving axles where I deduced the cog to be.
There is still a tendancy of both to sit back onto the sprung rear driving axle when under load ( or even a track perturbation).
On both locos the slide gear became detached from its carrier plate causing some very mis-shapen connecting rods. Since applying super glue to all four slide gear units they have stayed in place and given no further problems.
Whilst very happy with the end results they are not a patch on the GW Castle - both of mine perform well without the slightest input from me!
Having read the glowing reports of the rebuilt WC/BB & MN's I cannot see what would make them so superior. Any input on that Q?
Regards
Peter A Montarlot