Subtracting the soldermask layer from the silkscreen layer in gerber files

[mondalaci]

Hi guys,

I've generated gerber outputs for my PCBs and realized that there are lots of areas where the exposed copper is covered by silkscreen, potentially preventing solderability.  I know that some fabrication houses automatically subtract the (inverted) soldermask layer from the silkscreen layer but many don't and I'd like to have a general solution to this problem.

http://sourceforge.net/tracker/?func=detail&atid=409541&aid=3386121&group_id=33921 suggests that this feature has already been requested for gerbv and Gerbtool already has this feature but the latter seems to be very complicated and I'm clueless how to do layer subtraction.

(Please don't suggest me to include less layers upon generating my gerber files because there are some layers that are very useful and I want them all to be included.)

Thanks in advance!

Laci

[mondalaci]

I'm using Eagle.  Couldn't see any such warnings.

[fgsantos7]

Is there any program that can invert the a gerber file?
In my case I want to invert the silkscreen gerber file, but I can't do it already in my PCB design tool (PADS).
Does anyone have done it already?
Thanks,

[lorth]

I've generated gerber outputs for my PCBs and realized that there are lots of areas where the exposed copper is covered by silkscreen, potentially preventing solderability.

Not sure if I fully understand your problem. Since you have access to the original PCB layers, why don't you move the Silk there? Put a rule in your EDA's DRC that doesn't allow silk on exposed cooper.

[mondalaci]

lorth, Please note that I asked this question 3 years ago when I was a 100% electronics n00b. 

Since then I moved from Eagle to KiCad which has an automatic silkscreen clipping feature that takes care of this kind of stuff.

[lorth]

hahaha I didn't see the time on that post! hahaha

[eliocor]

Is there any program that can invert the a gerber file?

You can simply:
- open your generated gerber file with a text editor
- search for the string %IPPOS*%
- replace %IPPOS*% with %IPNEG*%
- save your file
 

[kanurys]

Do you mean to have the solder-mask removed over copper so text is shown in copper, kind of like a solder-mask keepout to form text? I'm not sure I fully understand the goal yet.