User Guide

Unitsinthe ApertureConfigurationFile
When automatically generated with the GERBERAUTO driver, the ap
-
erturetable(wheelfile)containsvaluesininches.
If your pcb manufacturer insists on mm units, you can achieve this by
alteringthe GERBERorGERBERAUTOdrivers.
In order to do this, use a text editor (one that does not introduce any
controlcodes)toeditthe eagle.def file.Lookfortheline
[GERBER]
or
[GERBERAUTO]
andattheendofthatsectionadd/editthelines:
Units= or Decimals=
Example:
Units=mm
Decimals=4
To avoid problems arising from rounding errors during the conversion,
a toleranceof 61%shouldbeallowedfordrawandflashapertures.
9.10 FilmGenerationUsing PostScriptFiles
Whereas, until a few years ago, Gerber files almost exclusively had to be
generated for the manufacture of professional pcb films, there are today
PostScript raster image recorders which offer a high-quality alternative
whichissimpletohandleandeconomical.
With the PS driver, the CAM Processor generates files in PostScript for
-
mat. These can be processed directly by appropriate service companies
(mostofwhichoperateintheprintindustry).
For PostScript recorders the Width and Height parameters should be set
to very high values (e.g. 100 x 100 inches), so that the drawing is not
spreadoverseveralpages.
Films and drawings that relate to the bottom side are usually output in
mirrored form (Mirror option in the CAM Processor or in the PRINT
dialog).
The EPS driver generates Encapsulated PostScript files, and these can be
furtherprocessedwith DTPprograms.
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PreparingtheManufacturingData