Valve gear problem

[John Billard 1Participant @johnbillard1]

I would greatly appreciate some advice.

My project (since 2000 with interruptions) is building a 5″ Great Eastern Super Claud.  Basically my own design but with reference back to the Martin Evans version for various aspects.  The tender is completed in some detail and I have made the boiler which has been proof tested by our club inspector.

As part of the design I have followed GER practice by putting the valves under the cylinders.  This has led to a direct drive valve gear, outside admission, with loco links. For the basic layout I followed the Martin Evans Jinty design with adaptions to suit the engine including the valve chest/valves which is Evans dimensioned.  The resulting valve gear design was verified by using the Hall S-1 program which gave good valve events and steam distribution on simulation.

However on attempting to set the valves I have run into great difficulty in setting the eccentrics to produce any satisfactory result at both ends of the travel and in forward/reverse.  Clearly something has gone wrong and I am at a loss to go further.

Can anyone help?  I will willingly make changes though I would regard the cylinder and crank axle as fixtures.

I would like to have the engine running one day and time is not on my side!

Best wishes

John B

 

 

 

[duncan webster 1Participant @duncanwebster1]

John you have a pm

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