I really just wanted to jump into this project, mainly with out thinking/looking
I've seen [Carl]'s projects hear and some of his progress on twitter. I popped open EagleCAD and went straight for the ULP's.
copying the spec's from the original:
I went with 0.5 mm for the width and 30 turns as specified
I used 0.2 spacing as that is the minimum for flexible PCB from OSHpark
Which dumped out this:
I wasn't sure if i was going to be able to line up the vias since Eagle is a baby. I am going to look into separating this as well as spacing out the center to make a more usable coil for metal detecting.