Critical bug in DRC rule for "Minimum Drill" size

[chipdesk]

I changed the Minimum Drill size from 0.35mm to 0.15mm in the DRC rules of my project:

Unfortunately, this has absolutely no effect on my board. I clicked both the Apply and then Check buttons in the DRC window, but Eagle keeps indicating all drills with a diameter below 0.35mm as an error.

The error is indicated to be on layer 20 (the Dimension layer):

I use the latest Eagle version: 9.5.1 Premium

[Anonymous]

This sounds similar to the infamous Airwire bug that has been mentioned before. I'd recommend closing then re-opening your file. This method works for the Airwire bug so it would be interesting to see if it applies to this drill size bug too. 

[chipdesk]

Negative,
Closing Eagle and restarting the project has no effect.

[jorge_garcia · Accepted solution]

Hello @chipdesk,

I hope you're doing well. Whenever this happens almost always there's a conflict with the netclasses. Check your netclasses and make sure the default netclass is set to 0 for all of it's values. If it's set to anything but 0 then it's possible for these settings to override the DRC.

Let me know if you continue to run into issues.

Best Regards,

[chipdesk]

Hi @jorge_garcia ,

Thank you so much for fixing the problem! It was indeed due to net classes. I completely forgot about them.

If I may give some feedback: there is already some useful info written at the bottom of each DRC tab. Perhaps you could add a warning there, like

 > "Warning: DRC rules can be overridden by net class rules. Click here to check your netclass rules."

That would have saved me (and other users) a lot of headaches 😉

Kind greetings,

Kristof Mulier