Thanks for the welcome. I have built a couple of 3" ones, a Marshall S type road roller and a self designed Fowell Box Patent haulage engine. I was going to build a Burrell-Boydell engine also in 3" but have had to downsize machinery so decided to build the Burrell at 1.5" or 1/8th scale. This is coming along nicely and I'll post a picture when I find out how!
I still have my original hand drawn drawings of the Fowell-Box and am using them to learn how to use Fusion 360 to make a 1.5" version.
Brian