Spring loaded contour carving

Has anyone tried spring loaded contour carving?
I am looking at carving things like seashells with names. etc.
I am thinking about using a spring loaded Dremel tool with a follower wheel to follow the contour, and allow depth penetration set by the follower wheel to carving bit ratio.

Does anybody know the thread size of the three holes on the DeWalt 611 mount? As I was looking to use these to mount the contraption.
Please advise,

The holes are M4 x 0.7

Here is the grabcad file for the DeWalt MountDeWalt Mount.pdf (254.6 KB)

wow! thank you!!