This is the adaptation of the Vanda-Lay Duplicator. And the first (rather second) attempt to make it work. In the first one I used a timber block to hold the pattern and it was not sturdy enough. Now I attached the pattern holder to the lathe bed and it is much better. I know the shortcomings of my solution and I realize that the V-L is better in more than one aspects. Their cutter can be working by hand, independently of the feeding screws, mine is not. Their cutting tool is a small (3-4 mm?) diameter silver steel which slides in a bigger dia brass tube. The tip of the cutting tool and that of the follower tip is much more similar to each other. However, my setup allows me quicker roughing out and I don't have to change to a different cutter for the details.
So I am working on some details to make this solution better as it needs some measuring and manual cutting as a consequence of all the above. And then I have an idea which I plan to implement. Instead of making the pattern (at the moment it is made of 1mm brass plate) which is a job and a half in itself I plan to completely manually turn the first piece on the basis of the drawing, then using this as a master, fixed between two tips as the pattern. Watch this space.
Nice I haven't heard of that duplicator, I had one made from aluminum that I bought from ebay a bunch of years back that had so many issues it wasn't funny. I started casting things I needed multiples of but even that was work to get them to machined finish I still had to chuck them up and turn them. I cleaned them up with files and sand paper so wasn't really saving much time. I still do the old one at a time thing, but now that I'm interested in scratch building a duplicator is in order I think I can build something to hook to the rear bed way on the back like you have that will clamp on to hold the pattern. the follower on the cross slide will be easy
what you have seems to work well you cannons look great ill go look at that post. Im pretty good at fabricating things from metal and I have a lot of Machining exp in a manual shop. shouldn't be to difficult