I am used to using move /copy to duplicate components.
I have been trying to use the same technique to pull out one of the copies from a model so that I can add tenons etc. I have been finding that the changes are not reflected in the other instances of the same component. So I am having to reproduce the same drawing on multiple copies. Can someone tell me what I am doing wrong about this process?
Sounds like you have groups rather than components.
Can you share the model or at least a screen shot so we have a better chance of giving you a full answer.
Indeed, it does sound like you have made groups instead of components. Or could it be that you’ve opened the component for editing and are using Move/Copy on the geometry inside? I mention that because I saw that someone had done that yesterday on a model they sent to me for the same problem. Not only does it cause the problem you’re seeing, it creates other problems, too.