Designing valve gear - how to?

[alan2525]

I'm dabling with the idea of getting some rodwork lasercut for my much modified locobox bagley loco 'Wendy'

I'm thinking of using a simplified walsherts as per Roundhouse, so it would just be an outside eccentric, with a reversing quadrant. I'll have to look up the specs of the cylinders to calculate the stroke of the valve , but how to work out the lengths of the other rods?

There must be some kind of formula or method? I've got the valve gear simulation software but those are for the valve gears on actual locos, with the additional union link and a few extra variables to complicate matters a little more, nothing 16mm loco specific!

Can anyone help!

[MTA]

This might be of some help, Alan.

http://www.tcsn.net/charlied/

EDIT: Actually just read your post and noticed you had this software, D'oh!

There might also be something of use on this page:

http://www.gilesfavell.seriouslyinterne ... mation.htm