The Push and Shove router is not perfect; very good, just not perfect.
From time to time, it gets very stubborn with how it wants to route a trace, when I can’t see why it doesn’t want to do it the way I want.
In the end, I have ended up with several ZERO length track segments that are a bunch of closely spaced circles that go nowhere and resemble the appearance as if the router is just blasting away with a micro-shotgun.
Then, using the shooting world terms again, there seems to also be the “random” flier. One dot in the middle of nowhere for no known reason.
How important is it to clean these up before creating the Gerbers?
Like Justin (@jwpartain1), I don’t recall encountering anything like your description (as best I follow your description).
If these bits of copper are truly real, they should be removed from a moderate- or high-density board. A few pin-pricks of copper in the open spaces of a low-density board are tolerable, especially if you’re trying for the appearance of a 1960’s mass-market product.
You may be seeing artifacts left behind by a rendering engine or a video driver. It’s probably worth the effort to plot a set of Gerber files, then open them one layer at a time in a Gerber viewer. (I prefer “Gerbv” from the gEDA project rather than KiCAD’s viewer but there are several suitable programs in use.) If the copper spatters show up in the Gerbers then you have justification for figuring out how they got there and correcting the problem; if they aren’t present in the Gerbers then you can ignore them for now. (Just be sure to look for them when you do your final Gerber inspection before submitting the fabrication package to the board vendor.)
In my experience no matter how innocuous these specs of copper seem your fab will probably want to remove them. They may simply remove them without saying anything, or they may seek your approval to remove them or they might just reject the board altogether.
Edit: While KiCad quite frequently leaves little zero length tracks behind, usually hidden behind other tracks and don’t appear until you delete or move the track covering them, I haven’t seen clusters of them as you describe.
Yeah, that looks like the droppings left behind by an automated or semi-automated trace routing algorithm trying to find its way around a constraint. (You are displaying traces in “Outline” mode, right?) Almost certainly needs to be removed.
I think PCBNew has a “Cleanup” feature that may find and delete this sort of thing automagically. I have had mixed feelings about “Cleanup” features in other layout programs - some of them delete things that really should be left in-place. The other alternative is to (carefully) block-select the things and delete the selection.
Well… No, I wasn’t… but as you can see from the screen shot, I am now.
On a related issue, KiCad also creates an extra segment when it “auto-targets” the center of “off-grid” pads. I have deleted TWO of these, on my current project, and the DRC does not show as “unconnected” when removed. Should I delete these as well?
ON EDIT: Off-grid pads happen with parts that the manufacture seems to want a part to have both metric and imperial dimensions for their part. I have no idea why, but I have a few of them that I have in one design; very frustrating. I don’t mind using either system, but to have to kluge the two is an aggravation I’d prefer to avoid.
The image is not very distinct on my computer’s display. I wanted to confirm that I was looking at trace outlines, and not some VERY narrow random scribbles.
If it’s what I think it is, I’d leave it in place.
