JLCPCB vs square cuts?

Hi,

so far I used regular rounded holes but I need to make 3mm wide square holes and I was wondering if it was possible with Kicad

also is JLCPCB (or other manufacturers) accept these sorts of cut-outs

thanks for your help

JLCPCB will do square cut outs but they will have rounded corners due to them being routed with a round bit. I believe off the top of my head they use a 1mm router bit and there minimum cut out size is about 3mm square. All the details will be on their website under capabilities.

I can still file them afterward

I strongly discourage it.
It will need laser cutting, which is costly.
The usual way to do it is to use “dog-bone” cutouts instead. These are easy to manufacture.
This link explains:

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On their website:

it says:

Not sure about the minimal radius though. I’d ask them via the online chat. They are usually very helpful.

The screenshot you posted is already from the Drill / Hole Size section on their website. Just above that they state the widths for routing slots:

Yes, that is a possibility. Not such a big issue for DIY or small batches. You will loose the plating in the corners.

Another option is to add “dog bones” This is a common name for creating extra room in corners such as shown in this picture:
image

You can easily make a footprint for it. I have had positive results @jlcpcb

thx guys… I dont have enough room for dog bones thou
I need to place SK6812-MINI-E (rgb serial leds) that have legs in the middle of their body height

If you order your PCB’s like that the holes will have rounded corners. Even without the rounded corners the holes will be too small. The plastic body of your LED’s is 3.2mm, and that is already bigger then your hole. You will have to make a choice how to fix this, or you are in for a lot of filing.

I’ll indeed add some margin…thx
I’ll file the corners

When needed for Square Holes, I use Square Drill-Bits… :rofl:

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Now that I see your layout, a possible solution could be to use reverse lead-bend LEDs and a round hole for letting the light through.
That would be the SK6812MINI-ER.

Something very similar to that illustration actually exists and is used for making square holes in metal.
“Square broach” is the term to search for, if someone is interested.

Downside: broaches are really expensive and need support tooling for guidance.

I have many yrs of experience with Stamping Machines for making Electrical Contacts used in Connectors… I hear the sound of 12 machines in my sleep!..

I want to avoid bending the leads as the flatter the leds, the better

Spare Parts #13 - Making A Square Broach (youtube.com)

Is there any reason you need so much space between the edge of the board and your through-holes?

why not ? this is project specific, I need to solder wires on these pads

You don’t understand.
The reverse-bend LED is “upside down” and shines its light toward the PCB substrate. The manufacturer already did the bend. Thickness is the same.
But you need a hole in the PCB under the LED to let the light through.
I meant it as an inspiration to think about the mechanical design differently.