I have a friend who works will be able to do this for me and was wondering if anyone here has alrady done it? What was the results?
I have so far decided that an oval shape with screwed barbs either end; would be best. This being made out of an aluminium block (easier to get hold of!), being milled out and a perspex sheet screwed on the top.

What do you think? Should i try for copper - is it worth the effort? Has anyone got any plans of theirs?