TUTORIAL:
Assembly drawing plots from Gerber files, using GC-Prevue Version 8

Assembly drawings will show pads, through-holes and silk screen.

The best type of assembly drawings show names under the components, instead ofusing the silkscreen legend. But in uncrowded designs, the silkscreen willsuffice.

1. Top Assembly drawings
   1. Using GC-Prevue, have in view the following CAM files only:
      1. Holes—NC Drill (..\NCD<_job_>.NCD) Example: ..\NCDBASM7.NCD where"BASM7" is a 5-letter nickname for the PCB job.   NOTE: You'll needto make the via holes disappear. (See footnote²)
      2. Component outlines and reference designators—Silk Screen Top Gerber file (..\SST<_job_>.GBR)
      3. Pads—Solder Paste Top Gerber file (..\SPT<_job_>.GBR), or if there is no top solder paste, then the Solder Mask Top Gerber file (..\SMT<_job_>.GBR) (See footnote¹)
   2. Use File|Checkplot [F4] to print this view to the printer.
      • In the Checkplot popup window, set the Style: to "Normal" (as opposed to "Ball+Stick")
      • Use "Setup Printer" as needed to change the paper orientation to "Landscape."
      • Click "OK"
   
   
2. Bottom Assembly drawings
   1. Using GC-Prevue, have in view the following CAM files only:
      1. Holes—NC Drill (..\NCD<_job_>.NCD)   NOTE: You'll need to make the via holes disappear. (See footnote²)
      2. Component outlines and reference designators—Silk Screen Bottom Gerber file (..\SSB<_job_>.GBR)
      3. Pads—Solder Paste Bottom Gerber file (..\SST<_job_>.GBR), or if there is no bottom solder paste, then use the Solder Mask BottomGerber file (..\SMB<_job_>.GBR) (See footnote¹).
   2. Mirror the files to get an unmirrored checkplot:
      Edit|Mirror X [X]
   3. Use File|Checkplot <F4> to print this view to the printer.
      • In the Checkplot popup window, set the Style: to "Normal" (as opposed to "Ball+Stick")
      • Use "Setup Printer" as needed to change the paper orientation to "Landscape."
      • Click "OK"

Footnote 1—Using solder mask in place of solder paste to show surface mount pads in an assembly drawing—If the vias are tented, or covered with solder mask, the solder mask willwork fine for showing pads. If the vias are uncovered, then query the viasolder mask pad and set that aperture to zero ², as having the vias show in the assembly drawing will be too messy.

Footnote 2—To set the solder mask pads and drill holes to zero dimension on vias:

1. Turn off all layers except the NC Drill and Solder Mask files.
2. Click the mouse on a via and type the letter Q.
3. In the "Query" popup window, click on each unique aperture button shown(including the drill tool button), while in the drill rack or aperture windowthat pops up, set the dimension for that aperture to zero, then click "OK"
4. When all of the solder mask and drill tool apertures for the via are set tozero, click OK.
5. The vias will still be visible, but when you redraw the screen, or scroll it,they will disappear. (That is, almost; you will still be able to see their locations as tiny dots.)

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