Re: Mcewan Pratt 10 hp
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It is a shame that David lost his information but it reminded me that I had seen some images on the NGRM Forum of the blueprints. Like most drawings of this nature, they take a bit of time to interpret to work out where the designer thought that things like to controls should be positioned. Quite often what was built differed from the original design but these images may help with the approximate placement of controls.
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Cheers, Robin -----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of David Woodcock via groups.io Sent: 20 July 2023 22:22 To: [email protected] Subject: Re: [o14] Mcewan Pratt 10 hp Very short wheelbase 4-wheeled locos don’t need compensation provided that they have been assembled correctly as the tolerances between the axles and the bearings provide just enough flexibility to do the job - unless the track is really awful. In this case, with a jackshaft axle to be driven as well compensation is actually undesirable. There isn’t a huge amount of information out there on the prototype loco (not helped by the fact that were a number of variations even within the small class), and the one survivor has been so heavily rebuilt that it isn’t much help either. When I first got the KBscale kit, I set about bringing all the information I could find together in the hope of producing as near accurate a model as possible. I had got a long way down this path and had produced a good detailed drawing when I lost it all to a hard-disc crash (on a MacBook too), I gave up after that! (Although I still have the kit.) The etchings are for the most part excellent but there are other issues which won’t be easy to overcome. On my kit, the wheel tyres and wheel centres were rather less than an interference fit, for example, and securely fixing the very nice sandbox castings to the running plate could be an interesting exercise too. On the prototype there were some “interesting” angle fabrications behind the sandboxes which are difficult to see in the few surviving photographs but would be very visible on a model - and they aren’t included in the kit. Finally the controls in the open cab (so also very visible) were far more complex than the kit provides for and most surviving photos (and the drawing in an early REVIEW) proved to be misleading. I eventually tracked down a photo of one in a scrapyard pile which showed the controls - it was in a long past copy of the NGRS “The Narrow Gauge”. David Woodcock Champlon, Belgique |
Robin Edwards
