Concept: Eeschema Mechanical Sheet

I deleted the mounting holes from a schematic, and the holes went away in PcbNew.

ALL of My complaints would go away if there was a mechanical layer/sheet in Eeschema that was not visible/wouldn’t print in the main Eeschema schematic; yet it contained the physical elements of the board.

One other idea is to possibly have a menu selected “Board Layout” Symbol, and a “Board Layout” Footprint that were dedicated to the project.

I usually ground my mounting holes. But perhaps you might not want them grounded. My thought is to expand the discussion by mentioning a couple of poor workarounds (?):

  1. Start out with the holes grounded or connected elsewhere, then lock them (can be done in layout in 5.99) and delete them from schematic?

  2. Just place them in the layout without any (net connection or agreement with the schematic) (??)

I don’t mind seeing them on the schematic. I put them in a corner, usually one caused by the title block. Perhaps you could put them in a child sheet?

The other way is to add them to the PCB and then lock them so they won’t be touched by updates or deletions.

Have you thought about putting them outside of the “paper size”?
This seems to work for both printing and for plotting to .pdf, but it does not work for plotting to .SVG.

Alternatively you can of course also add a hierarchical sheet for “mechanical” or “miscellaneous” parts.

I do it the same way as BobZ & retiredfeline myself, I just put them on the schematic for eaze of mind of never loosing them accidentally. I am making more use of hierarchical sheets lately. Even for a small microcontroller board I put the power suppply section (SMPS and/or linear regulator for 5V-> 3V3, decoupling capacitors) on a separate hierarchical sheet, and that sheet usually has plenty of space for a few mounting holes and extras such as placeholders for footprints for logo’s.

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If you want a separate sheet for mechanical items, what is stopping you from dropping an hierarchical sheet onto your top level (or first) sheet specifically for mechanical things. Call it your “Mechanical Sheet” and Bob’s your uncle.

This just seems like a cludge. I’m considering creating a Footprint for every board with an outline and holes, but that seems a bit like a cludge as well.

I just wanted a way for Eeschema to keep mechanical items in place, but not be visible/printable on the schematic.

The simplest method has already been mentioned.
Just lock the footprints on the PCB.

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On the lowest level I do not understand this “obsession” of wanting to remove these symbols from the schematic. It brings back some memories from very long ago. I once had the idea of not wanting to put connectors in the schematic. Maybe it was partially because I thought they “wasted space” or “they didn’t really do anything” electrically.

These day’s I try to keep it simple. Schematics are not made to look good. Schematics are to present information about an electronic circuit and PCB. Mounting holes are a part of that, and thus should be on the schematic.

A repeating request is an ability to be able to add some things to the BOM that are not on the schematic or PCB. For example some screws, rivets or distance bushings or a potentiometer that’s connected to a cable to a connector on the PCB. Maybe there is an issue on gitlab related to this.

In KiCad, the schematic symbol is the “root” of a “part”. and all other attributes, such as value and footprint link are attached to it. I think this may have to change at some point, for example for the “database driven libraries” that some people find very important. For things like that a more abstract container of a “part” and in which the schematic graphics is just another (swappable) attribute seems more appropriate. There are some initiatives to at least think a bit about this for KiCad V7.

I just did a little test by setting both the Refdes (a.k.a. “Reference”) and the Value of a resistor to invisible. This leaves just the pins and the graphic square visible on screen.

One thing you can do as a workaround is to make very small schematic symbols for your mounting holes and then “hide” them somewhere on the schematic, for example in the title block graphics. It’s also an ugly workaround. I have not tried what happens if a schematic symbol has no graphics at all. This may make it difficult to handle it in the GUI (select, move, delete, etc) It will still show up in Eeschema / Tools / Edit Symbol Fields and probably the BOM too.

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Here is how i do it. Most of my KiCad Projects have a top level schematic sheet which has multiple hierarchical sheets. In the top level sheet i also place a symbol, for every mounting hole, fiducial and, if there is one, a symbol for a footprint which defines the mechanical outline, hole positions and connector position (this footprint is generated from a imported DXF).
I don’t see any reason not to include them into the schematic. The schematic should have the information included on how to design the PCB.

Your goal to hide them when printing is not very smart. What do you do when you need to connect the mounting hole to GND? Then you would have to include some mounting holes into the schematic but not all, that would be inconsistent and it would be confusing because someone seeing the schematic may think there are only 2 mounting holes while there are 4 on the PCB.

If you really think it is a good idea to hide them, maybe you could make the top sheet to only include 1 hierarchical sheet with all the electric components (you can still add hierarchical sheets to that sheet) and place the symbols for mounting holes on the top sheet. When you want to print it, you can open the hierarchical sheet only, in its own project. Then the top level sheet would not be printed and the mechanical symbols would also not be printed.

I’ve never seen a schematic with holes indicated on it within the industry that I have the most experience in. I consider it professionalism to generate schematics that comply with industry norms.

TI EVBs design files are good example of having mechanical elements as part of Schematics.


Apple schematics all have mechanical elements(mounting points) included as a separate sheet.

And so many more use the same pattern, like CERN with HPM7177 as an example:

I never knew there was a standard that required to remove mechanical elements from schematics. I just learned from the examples above how one does good documentation.

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Just like Junction Dots, mechanical elements provide nothing other than unnecessary clutter on a schematic.

You can have them all you want, but why tell me that I have to have them? Especially since the industry that I have the most experience in does not do it the way that is being suggested?

There is one more workaround that I use: Draw the holes using circles in the edge_cuts layer.

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Except edge cut is done via a milling bit not a drill.
Thus the centres won’t appear in the drill file and equally will not be as accurate

I see that TI use a 4th quadrant sheet reference grid (i.e A1 top left) - like KiCad. Apple use a 2nd quadrant (A1 bottom right). Orcad uses 1st quadrant (A1 bottom left).

Obviously nobody would uses the 3rd quadrant - its so nice to see we can all agree on something. :wink:

Most of my PCB mounting holes are made to be clearance fits and don’t require that level of accuracy. I’ve never had a problem in the past, at least.
My component mounting holes do require accurate placement, but they are set up as drilled holes as part of my footprints so don’t need to be separate items.