Setting the eccentrics on a Stephenson’s valve gear

[GreensandsParticipant @greensands]

Can anyone provide a brief description on how to make the initial fitting of the four eccentrics on the driving axle of a model steam locomotive fitted with Stephenson’s valve gear.  Most accounts I have read are rather vague in their detail, simply saying that they should be fitted as shown in an accompanying diagram, Martin Evans being a good example of what I have in mind. I would welcome any ideas and assistance on the matter.

[Dave WoottonParticipant @davewootton]

This is something I struggled for months to sort out on my Rob Roy years ago, I even wrote to M.E about it and got a very helpful reply from Martin Evans himself. but I only really got it really right after being lent a copy of the late Don Ashton’s book on Stephensons valve gear which has a section devoted to setting, with a method of setting on a loco which is already assembled included. Don’s website is still live which has much valve gear information on it, and I think the book is still available from Camden, The book now covers both Stevenson and Walschaerts valve gear. Don’t be put off by the scary maths just following the book and making some simple jigs to set the eccentrics got my engine running well.

[GreensandsParticipant @greensands]

Hi Dave – many thanks for your helpful suggestions. I have now ordered a copy of the Don Ashton book.

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