Well folks
This is for anyone who wants to try carving letters into stone with there router but using water to prolong the life of the tool.
This was my solution to carving a piece of white marble, more pictures to come and a video of my process Click image for larger version.  Name: 20231022_134120.jpg  Views: 1340  Size: 237.0 KB  ID: 31995Click image for larger version.  Name: 20231022_131123.jpg  Views: 1345  Size: 165.1 KB  ID: 31996Click image for larger version.  Name: 20231022_131123.jpg  Views: 1345  Size: 165.1 KB  ID: 31996
I made meself a water tight box that fits under the gantry of my cnc and sealed it all round , put my piece of marble inside and wedged it on four sides then filled it with water so it covers the stone by about 5mm and then just let her go .
More photos to follow