Unfortunately, despite vigorous checking and triple checking of both the machine and the file, the machine mark the correct Z 0 height, despite resetting it multiple time, so when I came to cutting the toolpath, it cut too deep. I realised that this had happened when I flipped over the piece and the tool had cut into the machine bed. I decided to carry on with the cut then realising that I could try and reset the Z 0 height before re-cutting the second half, but it was unfortunately too late and whilst I successful rest the Z height, the machine had already cut too deep on the piece meaning the top curves of the oak had been cut flat. See below-
Unfortunately, I am unsure whether I have time to re make this on the machine now, so I will probably have to display the pieces upside down, displaying its underside, which has cut fine. If this hadn’t happened the piece would be beautiful, with the grain of the oak flowing the flowing forms really well. I was also using a brand new CNC bit which made light work of the oak and the finish was really nice which I am pleased with.
I am still unsure why the machine kept on resetting the Z 0 height and is something that I want to understand properly before doing another CNC machine cut.