Mechanical hole in PCB Layout

[qdrives]

For counterbored holes: some PCB fabricators mention it as "depth routing".

https://www.eurocircuits.com/Depth-routing/

[ebrahim]

Yes, I just found this is special hole called counterbored hole which, as you mentioned, I need to mark it and describe in the note. Thanks

[robertferanec]

In some cases, theoretically this could be maybe achieved the same way as when marking "backdrilling" - but as qdrives suggested, I would simply mark it and described in the manufacturing notes.

[qdrives]

Do you mean countersink holes?
If so, you would need to contact your fabricator on how to provide production details (ie drawing) for it.

[ebrahim]

Hello everyone,

I am working on the layout of a 4-layer PCB based laminated bus bar (there is no component in that and so no schematic) and need to make one mechanical holes at one point so that the radius on one specific layer is smaller than that of other layers. I have begun to work with Cadence Allegro and KiCad; But, couldn't find how to create such hole. Do you have any idea how to do it? Thanks