Roger, I have several books detailing valve diagrams, of which, as Harry said, the Zeuner is one. If you dont find what you want, let me know and I will copy some info and send it to you. Alan Stepney http://www.alanstepney.info Model Engineering & steam engine information pages ----- Original Message ----- From: "Roger Mason" <roger.g3tdm@xxxxxxxxxx> To: "Model Engineering List" <modeleng@xxxxxxxxxxxxx> Sent: Tuesday, April 17, 2007 8:46 PM Subject: [modeleng] Steam Engine Valve Events Hi All, As a school boy I can remember going to the local public library and diligently reading all the books on any kind of engine. Several books described a way of analysing steam engine valve events by drawing a circle and dividing it up and dropping perpendiculars etc. I would love to re-visit this technique, but cannot recall what these diagrams were called. So far searches on the Internet have proved fruitless, because I cannot remember (old age) the all-important name by which these diagrams were known. Can anyone help me out please? Cheers, Roger Mason, in St. Agnes. 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. -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.446 / Virus Database: 269.5.0/763 - Release Date: 16/04/2007 17:53 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.