I would hold-off on building this headphone amplifier from the supplied GERBER and N/C Drill files for just a little while. Similar to "Streamliner", I also have the CAM350 program and after I had imported all of the data files from the supplied ZIP-file and reviewed everything, in my opinion everything is at least "slightly hosed" and I wouldn't trust it to actually build something from!!!
As "Streamliner" has pointed out, not only are none of the GERBER files in alignment with one another, but none of the GERBER files are in alignment with the N/C Drill data files!!! Now..........since it is the job of the PCB fabricator to provide you with "GOOD" PCBs, they will have to spend the time to correct and fix everything that is messed up in order to get you a "GOOD" PCB!!! And.....time is money!!! So, it's very possible that your "Setup Charge" many end up being higher because of the amount of time spent fixing stuff.
Now.....since I am an "Official Old Fart" that sits here staring at my 34" curved monitor while collecting vintage dust, I have already gone ahead and aligned all of the data files together so they all have the same "0/0" origin point. Then, I saw some items within the SILKSCREEN Layer that bothered me, as it could create some confusion, so I am cleaning some of those items up as well.
The N/C Drill file is like way out-of-line from anything I would consider "NORMAL" in its format structure, so I will be tackling that next and then my CAM350 will output a better and newer N/C Drill Data output file for your PCB fabricator to use. Then, after I get that accomplished, I will check over the SOLDERMASK Layer and see if that needs any attention. I am certain that it will as well.
So.....HANG ON THERE!!!.....for a short while as I struggle through trying to get everything straightened out here with these files.
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By the way, "Streamliner".....which version of CAM350 are you using? How often do you use it?
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