Minimum Gauge Tank Engine
Project Diary (Pt 1)
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| Mar 2007 |
The paint scheme is temporary, but the engineering is permanent! The trials were very informative and generally successful. Despite temporary springing and odd weight distribution, the loco ran very well and the chassis design proved faultless. A couple of problems did come to light, as expected on a technically challenging design like this.... The radiating axle worked well but was a little tight in the lateral sliding motion. It became clear that additional side travel would be needed and a design scheme to achieve this will be developed in the coming weeks. In general I am very pleased with the trial and the work to date. |
 The
radiating axle components prior to assembly.
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| Feb 2007 |
 The
frames have been assembled and I am making good progress on the
brake gear. Assembling the frames was a real pleasure for 2
reasons: The loco started to take shape, rather than being a
pile of bits, and all the parts fitted together perfectly.
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 The
side frames job was brought back in-house and the first set were
successfully machined on the Bridgeport. The plates are
considerably bigger than the table and the available travel so the
plates had to be re-positioned 3 times to achieve all the
drillings.
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| Jan 2007 |
 Metal cutting starts in earnest! Good progress
has been made on the frame and rolling chassis components - the piles of
bits ready to bolt together are getting bigger. Unfortunately, the
local engineering company who are due to drill the side frames on their 2m
CNC mill have been too busy to fit my job in..... Pretty soon I will
have to take the job back in-house or progress will be disrupted!The components that go onto the axles - wheels, axleboxes and flycranks are coming close and when they are all completed I will machine the axles. The radiating axle assemble is progressing slowly and the wheels and sleeve are ready. The spherical bush and axle, complete with spherical portion are still to be made.
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| Nov 2006 |  After
2 months of determined work, toiling over a glowing keyboard and
motion controller, the design starts to mature. The
major components are specified and detailed, the shape and style
of the final loco are beginning to appear. |
 The
first phase of production is the rolling chassis, including the
Frames, axles, side rods, brakes. Quotes are sought for the
profiles, specialist machining and materials. |
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 The trailing axle will be fitted with a floating radiating axle to allow tight curves to be negotiated, while maintaining the maximum possible traction. |
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The Walschaerts valve gear has been designed and optimised using simulation software. This proved to be a time consuming, iterative process due to the limited space available. However, the simulation indicates that a well balanced motion has been achieved; this will ensure that the loco will run equally well in forward and reverse directions.
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| Sep 2006 | Design work starts in earnest.... The boiler options are assessed and supplier is chosen. |
| Mar 2006 | Planning starts and the first advertisements appear. |
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-
The
sun shone in March 2007 for the emergence of the 1st prototype for
track trials......
