Craig vk2zcm wrote:
> I had a play with a piece of printed circuit board sitting flat copper side down on the surface of the etchant It was connected to a tiny variable speed motor which made the board orbit. While the refresh rate was fast It etched the board twice as quick around the edge and hardly etched in the centre, not successful at all. My thoughts at the time was to try a linear motion but never go around to it
>
> Craig VK2ZCM
>
Thanks for sharing your experience. I guess the motorised cam wheel idea
won't work then. I can't explain why that would happen, but I believe you.