Just joined, hobby level

[black5f]

Hi

A bit bored tonight. Looked at your site, Good stuff mate! Had a few whiskys so may be errors! If you need to do other regular shapes just replace the circle equation with your own but it assumes a hemisphere and cheats by using the centre to tool contact as the normal, for elipses etc may be different but for regular shapes you can use the focus. Anything planar is easy. If you let me know the equation of the surface I will tell you the eq of the normal. These are just the finish cuts of course, you will have to cut the other material out with concentric circles keeping z constant. Other surfaces are the same, just need to know the normal vector. Actually you could incorporate a tool deflection number as well relatively easily. This is all to the centre of radius of the tool, just adjust the z path by the radius if you need to work to the tooltip.

Something to play with ...

http://homepage.ntlworld.com/tombayes/public/Book1.xls

Change the numbers in red.