Noob help with vias dimensions

Hi all,
I am new to KiCad and love it. I just sent my first PCB to a factory and it was refused as the vias were to small. They stated

The holes are 0.4mm diameter (which is fine), but the ring around the hole is about 0.1mm (so, a side-to-side total for the via of 0.1+0.4+0.1=0.6mm. I recommend decreasing the hole size to 0.3mm and leaving the side-to-side total as 0.6mm. Then you’ll have 0.15+0.3+0.15=0.6mm. And it’s the 0.15mm minimum annular ring size that you’re after.”.

This is a screen shot of my Design Rules

I have attached a link to a screen shot of my Rules Editor. Can somebody confirm this is where I change it to please. Also once changed I take it I have to delete all vias and re-draw them again? If this is the case, I did try this on a test board and couldn’t see any differences. How can I verify that it has changed them.
Is there a Windows program or web site that I can use to upload my Gerber files which can show me all the dimensions?

Thanks in advance for your help.

Just thought, I know it would sound obvious that I just change the ‘Via Drill’ from 0.4 to the 0.3, it it that simple and would I need to delete and re-draw all my tracks that have vias?

You just need to create a new via rule > Design Rules > Design Rules Editor > Net Class Editor, hit [Add] net class button… and check the other tab ‘Global Design Rules’ for minimum via diameters, in case it want’s to abort (the globals must be equal or less than what you want).
Once you got that… in your pcbnew editor window… top left, note the [Via: blah blah] button… select the desired via dimension you want and which you created just moments ago.
Now hover with your mouse (no tool active) over a via and hit [E]… repeat as needed.

For a faster way (depending on how savvy you are with a text editor and if you need to change ALL vias) you can also open the .kicad_pcb file and search for lines like these:

(via (at 152 110) (size 0.6) (drill 0.4) (layers F.Cu B.Cu) (net 10))

Some search&replace foo and this could be your fast ticket out :wink:
Be careful though, PTHs in footprints use (size a.b) (drill x.y) as well and are in the very same file…


I’ll be watching for replies to your questions from people who really know some answers, because I don’t really know.

In other PWB Layout programs I’ve used, there was a command (on a drop-down menu) that told the program to modify a footprint on a board according to another version of the footprint. You point to the library containing the “new” footprint, click “OK”, and hope the new footprint doesn’t include copper in places where you don’t want it to be. (The “new” footprint didn’t have to be newer in the sense of file creation times - the feature was also useful for reverting back to an “old” version of a footprint after an unsuccessful experiment.) You could make the changes to one footprint at a time, or a selected group of footprints, or all instances of a particular footprint. At this moment I’m not at a computer where I can look to see if KiCAD has a command to "change all vias of size ‘X’ to size ‘Y’ ".

Be careful about changing the size of the via holes. If your board fabricator suggested 0.3mm then I believe they have their feces amalgamated and can reliably produce a 0.3mm hole. For some board houses, 0.3mm is either right at the edge, or outside, their “normal” capabilities. They will either refuse the job, or add a surcharge for the smaller holes. (Being a coward at heart, my vias are routinely 0.018" (0.45mm) holes with a 0.038" (0.97mm) pad.)


Typo of the year right there. :smile:

1 Like

Thank you #dchisholm for your reply.

Thank you #Joan_Sparky for saving my life. I had adjusted the ‘Global Design Rule’ and thought I had sorted it, but didn’t press ‘E’ over each of the vias. I tried your suggestion and I saw them change on the screen, so am sure that it works fine.
I will remember in the future to set this before I make any boards so they all use 0.4 as the drill size and then 0.7 as the diameter as this should then work for all suppliers.

Thank you so much for your help.

damn, I did read that too and expected it to be some kind of english-locality expression… LOL

you’re welcome

[quote=“Joan_Sparky, post:7, topic:1598, full:true”]

damn, I did read that too and expected it to be some kind of english-locality expression… LOL [/quote]
It’s derived from a somewhat crude U.S. slang expression that entered our dialect around the mid 1970’s. College students of Electrical Engineering may appreciate the material surrounding that phrase in the post at - look in the paragraph after the second quoted segment.

In the future I’ll work harder to eschew obfuscation.


1 Like

Wow, I had no idea, I thought you meant faces, but then that doesn’t really make sense either. Thanks for the clarification!