Walschaerts Valve Gear Explained

PLEASE NOTE - this model and explanation contain a glaring error. That is, at the neutral position, the valve ports should not open at all. Thanks to Dave Squire for his keen observation. I'll hope to revise the model and make a new video, soon. -BL
For steam locomotive enthusiasts who've always wondered what all the complicated rods and linkages do. As an instructional video, this is admittedly still a work in progress. So, your constructive comments are welcome. Also, the model shown is one I'm trying to develop for sale, as a kit. If that's of interest to you, please send a private message.