How to Make Oval or Slot Holes on PCB?

Could someone tell me how to lay out oval or slot holes on a PCB using KiCAD?

I am working on a PCB layout that needs to put a USB connector on it . The connector requires 2 or 4 oval or slots holes, plus 5 surface mount pads. I could just make a round hole in the place of a oval or slot but it may not provide a tight mechanical grip to the connector.

You can define oval drill holes. BUT there have been issues with that.

a) not all gerber viewers seem to display these slots correctly, can’t really verify the files that way
b) plated slots are not supported by all PCB manufacturers (e.g. oshpark)

First I’d make sure your PCB manufacturer does actually support plated slots and then ask them how they would like to have this information given to them. Maybe they want it on an additional “routing” layer, maybe they do support oval drill holes.

Thank you MadWorm for your great advice.

Time for the reporting back now…

I took a risk to use the oval/slot PTH in my PCB, in a way that if the slot was not plated correctly, I had some extra tracks to connect to both sides of the oval pads. Now I’ve got my PCB back, with a great result. All oval slots were drilled as designed and plated correctly, thanks to KiCAD (hey developers, THANK YOU ALL!).

In case you may want to know, I had my PCB made through ( my second time of using them), and I am very happy.

I am using the development version of KiCAD that is built and running in Ubuntu.

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Got any photos of the slot & gerber file rendering?

Here is the gerber file rendered by KiCAD’s GerbView.

For the photo, I’ll try to take it when I find a good camera, because the oval holes are very small, and I have to look at them under my 20X micro scope.

But using “gerbv”, it only shows a single round drill hole, not an oval.

So KiCAD’s GerbView handles renders the drill file better.

I’ve had this issue as well, with the same result. Worse, the board vendor’s visualization tool is gerbv based and so rendered incorrectly. It took a few rounds of email with the board supplier (and a change of supplier, the first would have failed) to confirm that I would get what I wanted. They arrived and work perfectly.

Sorry for bumping old conversation, but I didn’t see KiCad’s Gerbview render it as you saw it above.

I have a plated oval through hole and this is what it looks like in KiCad’s GerbView. It looks the same in gerbv. What you are looking at is a 3.5mm jack. There are four plated through holes. They are the light blue color. They are represented by an oval shape with a drill in the middle.

In the past I have indicated slots in the Dimension (EAGLE) or Drawing layer.

As you always should, communication with the manufacturer is key. I’m waiting on a reply. Just curious if anyone has been through this before and seen these plated slots interpreted correctly by their mfr.

Did you use the File.Load EXCELLON Drill File option in Gerbview ?

What you have plotted there looks less like a Drill-file result, and more like a Drill-drawing, plotted as gerber.
The ‘x’ on Vias are a clue these are symbols, not drills

The top image above, is what you should see on Gerber and Excellon overlays.


Thanks PCB_Wiz… that was the problem.
I loaded everything as Gerbers.

which version of gerbv are you using?
the dev version should be fine with slots

newer versions seem to render correctly. Note that my post was over a year ago

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I just want to say thanks for pushing me in the right direction. I just now built gerbv under Ubuntu 16.04. It’s going to be sweet having slot holes =D

It was as simple as this I think (there may be more dependencies I didn’t run into). From instructions on

sudo su
apt-get update
apt-get build-dep gerbv
apt-get install autopoint sp libcairo2-dev
git clone git://
cd gerbv
make install