Does anyone know if circular/arc tracks can be made in 7.0? I searched the forum and there were comments around v5 that support for such might be coming to 6. But I have not seen anything to suggest that they’re possible (without scripting or plugins) in either 6 or 7.
I’m attempting to create a board with a number of circular rings around which WS2812B LEDs will be placed. A physical sample I have from AliExpress shows that is what they did for ground and vcc, and it seemed like an elegant solution.
The best I can do is a an octagon, which works fine, but isn’t exactly what I was hoping for.
I am able to draw a circular track on the copper layer, but I can’t assign the circle to a net or connect tracks to it. If I replace the octagon with a drawn circle afterwards I am guessing it will manufacture fine, but I then don’t have access to the DRC tools to catch my other mistakes.
Suggestions? Am I missing something? Or is there a good plugin someone can recommend?
Do not mix up “tracks” and “graphic entities”. Graphic entities do not have net name information, and even when placed on a copper layer, you can’t use them as tracks.
KiCad does support arcs in tracks, but It is understandable you missed them. There are currently hardly andy tools to directly draw them in KiCad. The only tools available is to add fillets between straight track segments.
Do this:
Draw a few track segments with corners.
Select those track segments.
Right click and select “Fillet Tracks” from the popup menu.
After you have added some fillets, you can change their radius by dragging the arcs.
There is also the quite impressive “Round Tracks” plugin made by Mitxela.
You are right about that. I even saw this when experimenting with the feature this morning but somehow it slipped my mind again before I wrote it down, so it’s good you added it.
But still. there is no first rate: “Draw arc track” in the menu. circular tracks are only made as a “fillet” feature in corners. This is still far from ideal when your project relies on circular tracks. Take for example this old post (too old for KiCad V6)
I was in doubt why I added that very old link above, but I know again. It uses a bunch of concentric circular tracks over a big angle, and with KiCad’s current tools it is still very difficult to draw such a thing.
KiCad’s current tool is completely specialized in fillets, and if you change their radius, the center point moves. For that camera PCB you really want to be able to define the center point of the tracks.
I had played around with the “Create from Selection” tool, but I didn’t know that it was not available for closed objects like circles. Then when I tried it with an arc, I didn’t understand that it creates the track object as a COPY that is BEHIND the existing arc object. So, when you select it to assign a net, you’re still selecting the arc, not the track. They key being that you must long click on it and select the track (and/or delete the original arc).
So… for those who enjoy step-by-step solutions…
Create your arc as normal, though it might be easier to do so on one of the other layers. I used the front silkscreen layer.
Right click on the arc and select “Create from Selection” and then “Create Track from Selection”
Then either long-click the arc (or hide the silkscreen layer). You can then select the track and/or delete the silkscreen arc.
You can then edit the properties (press E) and assign the track to a net. This will allow you to actually connect the track to other things.
NOTE: It will not allow you to create tracks from circles, since there are no endpoints for it to use as connections. However, you can create two arcs to create a circle, but it does confuse the DRC and will report them as unconnected. But it’s close! And this solution works for me.
It keeps the original item selected after the “create from” action, so you can just do “create from” and then without selecting anything else, hit delete to remove the original object.
Hi, Very interesting but in V7.0.1 “Create tracks from selection” option is mising. All I want to do is put a 270 degeree arc around an smd round pad to use as a ground for a UHF RF connector on my wideband amp PCB. So far it seems impossible with this version. I can make an arc just fine on the F.Cu using the create from shape function layer and put a small pad onto it that is set to GNMDPWR Net, but all connections only go to that pad, not to the arc.
I then tried using the footprint editor.
Added a centre pad (no1) then a second pad (no2) and entered the pad properties for no 2. I chose Custom circular base as shape. Next step custom shape Primatives. Selected ARC. entered parameters Centre point X=0, Y=0, Start X = -4, Y = 4, Width = 2, Angle 270. and I get a preview with an arc:
All get assigned to GNDPWR but will not connect as arc remains unconnected and seems to be in foreground. The ratsnet shows it wants to go to GNDPWR but will not accept a track.
Very interesting but in V7.0.1 “Create tracks from selection” option is missing
Than you have a very special v7.0.1 version. At least my current 7.0.1 installation shows the “Create tracks from selection” option in the context menu (see picture at the end).
Note (in case this is not clear): this option is only available in the board-editor, not in the FP-editor.
Note2: you have to delete the original arc after creation of the track. Otherwise the original copper-arc would prevent other tracks because of clearance-issues.
Note3: only exception for “Create tracks from selection”: it’s not available for circles.
Regarding your second task - defining a custom pad shape (an arc-shaped pad in your case) you should better use the new “Edit Pad as graphic shape”-mode instead of your shown workflow (“Pad Properties–>Custom Shape Primitives”).
You can find a short description at my answer (#2) at this topic:
The “anchor”-pad in this method is later the connection-point for your tracks.
screenshot as proof for “Create tracks from selection”:
@mf_ibfeew Thanks for that. I did not realise that create track it was not available in FP editor, although the clue is in the name. I needed a create pad option!
Following your link I have been able to achieve what I wanted, a central pad with an arc of a pad around it.
To prevent thermal breaks in the arc, I set the connections to copper zones property of the arc anchor pin to “Solid” and the Zone knock out to “Pad convex hull”. Not quite sure what the last one does, but I now have a fine arc for the connector ground and a solder mask over it.
The only slight issue I can see is that if the arc is anything other than ground or another power plane, the only connection point is the orignal pad. (anchor pad). The answer to that seems to be to add lots of pads around the arc all with the same number, then at least connections can be made to several points.
The only slight issue I can see is that if the arc is anything other than ground or another power plane, the only connection point is the orignal pad. (anchor pad). The answer to that seems to be to add lots of pads around the arc all with the same number, then at least connections can be made to several points.
Yes, adding more pads == more “connection”-points.
But thats mostly important if you start a track at that custom pad.
If you start from a foreign pad and try to end a track on the custom pad it should be possible to end the track at every pixel of the custom arc-shape. For electrical connectivity (run DRC) itself it should be unimportant if the track ends on the anchor point or somewhere else on the arc.
Also thanks for the feedback - first it’s good to see (for me) that a question is solved and secondly it shows (for future readers) that a recommended workflow is really working.
