Electronics Forum / CAD / January 2008

VK,
   There is no easy or simple manner for anyone to describe to you how to
rebuild/regenerate a drill file for your files. It can be done, it can be
done fairly easily by someone that fully understands what they are doing and
have access to a suitable Gerber editing tool. The key there is a Gerber
tool that will do file editing, typically any of the freely available tools
on the internet are just Gerber viewers. If this was a medium
size/complexity board with mostly SMT components, a few mounting holes and a
bunch of vias, I don't see why I wouldn't be able to manually ressurrect the
drill data in an hour or two, but then I have been doing PCB design for
decades. However I could spend three - four times that amount of time just
trying to explain to you what you need to do and how to do it.

   So far I have only seen one suitable answer to your enquiry from other
posters, seems most of them don't know how to read your original post and
they are looking for a reason to rant about AutoCAD or the precise
formatting of the Gerbers you have obviously inheritted from someone else.
Don't worry, having a fabrication drawing done in AutoCAD is very common, I
have done it that way for decades because ECAD/PCB CAD tools typically suck
big-time as a general drawing or documentaion tool.

(Note: the original post said nothing other than he had a "fabrication
drawing" in AutoCAD format, not a PCB design, nor Gerbers generated from an
AutoCAD PCB design.)

   There is one slight possiblity that could be your saving grace. Do you
have a Gerber viewer and have you loaded and viewed the Gerber files? Is
there a Gerber file that appears to be only the holes for the board? This
would be strictly circular flashes on a layer all by themselves, no traces
or other lines, except maybe a board outline, titleblock or drawing template
surrounding the board itself. These flashes are they sized appropriately for
the desired hole sizes (query them with your viewer tool and it should tell
you the aperture (flash) size, this should match to the drill sizes called
out in the fabrciation drawing if it contains the drill sizes). If you have
one of those layers in your Gerbers, almost any fabrciator can turn that
Gerber layer into a drill file in minutes and your problem is solved.

  If you desire, you could send me the files in question and I could give
them a looking over your you and then be in a position better advise/assist
you.

bveland at shaw dot ca

Autocad works fine for manual PCB layout. But each program that converts to
Gerber from dxf requires its own special format for the drawings. Going from
Gerber to dxf for a particular AutoCAD setup requires its own special format
out of the conversion program. Going from Autocad to other software also
requires its own special conversion software.

Bob

Hi David,
   The OP hasn't posted since his first message. I believe from the manner
I read his post, he has the Gerber files and a fabrication drawing and
that's it. I don't believe he has any PCB files or a PCB CAD tool. Sounds
like he got these fabrication files dumped on him with nothing else and now
he is trying to get them fab'ed without even an original drill file (or
possibly he does have a drill file but doesn't recognize it or it's format).

  I always try to pound into designers to do a simple readme text file to
be zipped up with their fab files. The readme lists all files, their
layer/stackup association, type (Gerber/drill/etc) and the particular
data/machine formats of each file. Then nobody ends up in these situations
or at least somebody had to do something intentionally stupid for them to
end up in this type of situation.