Before I start, thank you all for your help last time. I have had a couple of good weeks in the workshop and am just about ready to set the valve gear on my simplex. Thinking to myself i will have this running on air tonight (why does it take 20 times longer than you think) Anyway have looked at plans for about two days and i just Havant a clue where to start. I have had a look at a martin evens book but sadly it tells you how to design walschaerts gear but not really how to set it up. So 1 Where should the return crank be set in relation to crank pin? 2 What is the procedure for setting the valves? If this is going to be to complex to write on here could you point me in the direction of a book, maybe the good dummies guide to valve setting. I really would like to see my handiwork poor as it is running before xmas All the best Keith MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.