How to draw arch holes of specific width, angle, and radius in Kicad v9? Here is the picture for reference. I drew Edge cut arcs, but rendering does not draw cuts along arcs because arcs are not connected (and I don’t want them to be).
You can draw a closed arc perimeter in the Edge.Cuts layer, this will be interpreted as a milled slot.
Be aware that the manufacturer has limitations on the minimum size of milled slots, i’ve never done something smaller than 1mm. From the picture it seems to me much smaller than that.
But I do not want a closed arc perimeter as I’ve already stated. I just want to be able to cut an arc in an arbitrary free spot of the board. Let’s say 1 mm width to comply with the manufacturer’s capabilities.
Draw the outline of the arcs on the edge cuts layer.
Maybe using something like FreeCAD to help.
Draw the outline of the arcs on the edge cuts layer.
Sorry, I don’t understand your suggestion. I’ve already drawn arcs on the edge cuts layer - see the original picture.
Either way, if it requires an external tool like FreeCAD, I’ll wait for a Kicad-only answer. Or do you mean to draw all arcs I want in GIMP for example and insert it as an image in Kicad in some magical way to turn the graphics to NPTH pads?
How have you drawn the arcs?
ETA: you can’t just use a trace.
You need to draw the outline of the arc using a zero-width line.
That won’t work. You need to draw a closed curve.
A closed curve - well that’s exactly what I do not want. I want the arcs to be as I’ve drawn in the image.
This means edge cuts layer won’t do the job. Any other suggestions?
To clarify, I want to turn these arcs into NPTH holes.
Draw the arc as an OUTLINE.
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Pretty simple…
First, best to know the limits of PCB milling from vendor.
Then, set the Grid (for ease of use but, not absolutely necessary as you can override/change later…)
Draw the Arc’s as a Pocket. No need to worry about the Corners unless vendor is Punching the pocket (Mill Bit will naturally make the ends with Radius of the Bit).
I did Not bother with any dimensions beyond showing it was for ≈1mm (could easily have made it very accurate, if wanted)…
And, can use a Radius instead of Straight line at the ends…
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So that’s what @3Dogs meant by the outline!
Thanks for showing. I wouldn’t have gotten it had you not shown.
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While the video produced by @BlackCoffee is very good for explanation of the issue and for general usage (how a cutout shape is produced) there is a very handy tool to get the “arc shaped cutout” more easily (useful only after one understoods that a cutout always must consist of a closed shape).
- draw the desired arcs with the arc tool, set line-width to the desired width of the cutout (similar to the arcs in the very first picture), set arc-layer to “edge.cuts”
- select the arc, RMB-click–>context menu–>create from selection–>create polygone from selection
- in the opened dialog use option ""Create bounding hull, gap==0, line width==0)
- this will replace the “single stroke arc” with a arc-shaped polygone which is interpreted as a cutout
- note: depending on the pcb-manufacturer it might be necessary to use a linewidth!=0 for the cutout polygone, some manufacturers seem to ignore “width==0” items.
@johnbeard described in the Gitlab Issues a very easy way to create Arc cutouts:
- Start with a single arc (LHS)
- Right mouse click and then:
- Create from Selection > Create Outsets from Selection > Outset Items then fill in the details and the result is the middle drawing.
- Finally delete the centre original Arc.
Then either Duplicate, Move and Rotate or draw the total no. of arcs required in the first place.
I think many of us need to go exploring Kicad. 
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while @BlackCoffee’s idea is kinda simple but not very easy/quick, but it seems very flexible. for more simple shapes i’ve been using the arc or bezier curve tool to make the cutout i need. the main kicad “trick” here for turning it into a cutout/slot is to use the “create polygon from selection” tool. for the edge cut layer the slot/cutout needs to be an “enclosed” shape (but not a single line or arc).
FYI most pcb shops can cut a slot as thin as 1mm, but beware of the tolerances at that thickness.
here’s a quick video of how i generally cut creepage slots. (be gentle, this is my first video posted).
I don’t think BlackCoffee is simple, but indeed he’s flexible. 
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