Excellon Drill Holes Not lining up with Copper Layers - Stumped!

[Chris56000]

Hi!

I'm trying to make this experimental Z80 PCB on a CNC machine for my friend, but the Excellon *.drl file doesn't come aligned with the copper plots - the drill layer is about four times the size of the copper layers and way off the board!

I get the same result when I view the Gerbers in FlatCam and the open-source gerbv tool!

Can someone explain to me what's going wrong please?

This design isn't in any way confidential - here are the files to look at please!

Chris Williams

[radioactive]

See if you can find an option to output Excellon "24" format.

[Psi]

I've seen this sort of thing before where NCDrill files don't align to pcbs gerbers.

It was due to software making assumptions about what the units are.
From memory the file format said inches but the software ignored this and treated it as mm.