Please re-add support for Targets!

In version 7 of KiCad the PCB Target function was removed. Targets are a fiduciary - useful. The reason for the brute force removal of the target (from what I can read on the forums) was a response to people having problems with Target on boards sent out for fabrication. The “target” objects were fixed to the “Edge.cuts” layer. That could result in strange PCB shapes as some board producers would try to honor the outside borders of the “targets”

I’ve described removing “Targets” as a brute force solution - because the better choice would have simply been to move the targets off the edge cut layer to the margin or a drawing/fab layer.

For example:

)
(target plus (at 163.195 80.01) (size 5) (width 0.05) (layer Edge.Cuts) (tstamp 668EF6E6))
(target plus (at 163.195 134.62) (size 5) (width 0.05) (layer Edge.Cuts) (tstamp 668EF6E5))
(target plus (at 89.535 134.62) (size 5) (width 0.05) (layer Edge.Cuts) (tstamp 668EF6E4))
(target plus (at 89.535 80.01) (size 5) (width 0.05) (layer Edge.Cuts))

The better option would have been to:

(target plus (at 163.195 80.01) (size 5) (width 0.05) (layer Margin) (tstamp 668EF6E6))
(target plus (at 163.195 134.62) (size 5) (width 0.05) (layer Margin) (tstamp 668EF6E5))
(target plus (at 89.535 134.62) (size 5) (width 0.05) (layer Margin) (tstamp 668EF6E4))
(target plus (at 89.535 80.01) (size 5) (width 0.05) (layer Margin))

Why bring it back?

The targets make it easy to position where you want the zone fills of the board. With the targets placed, if the board shape needs to be changed AND you had excluded areas in the board, those targets on another layer allow the zones and exclusions to be recreated.

They make it easier to layout a board and the shape of a board without first designing the shape in an external mechanical CAD package.

Here’s a graphic that shows to “Targets” on the corner of a board, one marking the outside corner, the other “target” placed at the center of a mounting hole.

Again the reason for asking targets to be re-added is that functionality and the ability to use on older boards is lost by the removal of targets.

Re-add support for targets, but make the DEFAULT choice a margin layer. Then when the target is placed ALLOW the board designer to RIGHT CLICK on the target and chose the layer.

target_example

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i think that they are still working, just removed from the UI.
If you open a design that uses targets and ^c ^v to your design still works.

I agree that they are not fundamental but useful in certain occasions, and disagree to removing useful stuff just because someone is not capable of understanding how to use it correctly.

It’s recommended to link to old discussions if something relevant is available. This time this thread is a good starting point: Layer Alignment Target Gone from Kicad 7?

I do not fully understand the use of these targets in the first place, as a result I also don’t understand why they should be a separate entity in KiCad. Have you thought about creating a footprint for your target?

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That’s the main reason they were removed – the consensus on the team was that they would be better as a footprint rather than as a different kind of object.

FYI - Beacuse I Mill my PCB’s I use a Target-Footprint so I can print PDF for reference. Usually the target is at lower-left outside of Edge-Cut but, not always - that depends on the project.

Using the footprint is simple.

PDF example screenshot

Don’t think of targets as a spot to place a pin through such that you can align layers of mylar. That’s the old use for targets back in the 60’s, 70’s and 80’s. I’d done that.

But you could also create a mylar layer that only had targets on it that were used to mark an exclude zone.

The implementation of targets in KiCad upto 6, was treating them as a hard Target on the Edge Cut layer - that couldn’t be moved.

With targets placed on other layers that are not sent out to PCB fab shops, you have an increased functionality for the designer - if they choose to use them. If you use “Measure” and place one edge on the target – WHEN it’s directly over the target a small concentric circle appears - it makes it easy for accurate measurements.

I NOW have two devices with TWO different versions of KiCAD on them. One that is still using pre-7 versions of KiCAD so I have easy access to targets - and the other on KiCad 8+ that I regretted changing - because I had a board that I really wanted to use targets on…

During the development days of KiCAD 6, I believe I’d added a comment previously asking that a simple drop down box be added when right clicking so you could change layers. That still would work. It saves the need for using older KiCAD versions, then manually text editing the .PCB file to change the layer from Edge.cut to Margin.

That is a traditional use of the target on the outside of board edge. You could place targets inside of the main board (on a fab layer instead of the edge cut) and then use those targets to help draw out the actual cut out area.

Example is a long skinny board that I’d made with a hall effect sensor on the long end, then a wider end which had the voltage regulator, led, and a BNC connector.

I had used targets to mark all corners and locations I needed to measure.

When I sent the board off for fab, it was too narrow, the fab shop wanted it to be at least 2mm wider at some point. So I moved the targets around the wider portion by the BNC connector. Deleted the Edge.Cut layer and fill zones, then re-entered the edge.cut lines by connecting to the targets. The targets on this board had been previously moved to the “Margin” layer — BY MANUAL EDITTING of the file.

Targets could be more useful feature - if they were not fixed to edge.cut, it is the user interface that needed to have a drop down choice to allow the target to be placed on other layers.

Yes, but targets have the ability when the measure tool is used to help locate the exact center. The target object works fine, the problem was that it did not allow choice of layers.

Can you imagine the lack of functionality if the value or fab information was always pinned to a specific layer?

In the example at the start of this - I demonstrated that you can indeed move the target to any layer. The issue is that the UI for placement is no longer available AND it simply needed a choice that placed on the DWG layer as default with the user able to select the layer that they wanted it to be moved to…

Most other graphic objects allow the choice of layers - targets didn’t.

I had seen that - and I mentioned it but did not link to it.

The better solution would have been to change the DEFAULT target layer to DWG, Margin, ECO-xxx or some other layer - but add the ability to right click on the object and select a different layer if needed. That would leave in the functionality for those individuals - such as myself, while retaining the ability to place outside the board edge for the individuals doing their own CNC.

From your description I get the impression you use the Targets mainly as auxiliary construction points. This can also be done with a simple graphical circle, drawn on any wanted user layer. Margin layer works also.

  • the simple circle can be used for snapping lines/tracks/… during drawing
  • the simple circle can be used with the measure tool
  • the simple circle can be used with the dimension tool
  • with the layer panel all these auxiliary circles can be shown/hided with one click (enable/disable the layer)

Note that the snapping to different layers works only if you enable the object snapping–>snap to all layers mode. (look into the hotkey definitions to switch between snap to current layer ↔ snap to all layers).

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Take the measure tool and move over the top of any foot print for a resistor, capacitor or semiconductor. There is a big difference you’d notice. With targets, when you are over the exact center (within reason) a concentric circle is displayed. When you place the end of the measure tool Over a foot print of the self created objects (resistors, caps, led, etc). The center is not highlighted - instead you guess.

The Targets are easy to center over a mounting hole – you can spot if you are off center. The measuring tool with targets allows for better measurements when needed on the boards.

You loose functionality when you create the circles yourself. The measurement tool and targets combined add functionality that is lost. See my other comments - and then try and repeat.

@Dennis_Heidner plethora of ideas but, for me, I’ve been doing things my way for so long that I’d be lost starting another approach :rofl:

Aside from simply either(or, both) placing the Footprint or drawing one as needed, I have a Template that I use for most of my projects - it includes Both ways…
The White things are PCB hold-downs (holding clamps)

Try a Center Dimension.

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See my other comments - and then try and repeat.

I have done the following tests:

  • creating the auxiliary circle - drawing simple graphical circle: starting the drawing (centre point) snaps to existing pads, existing anchor points of footprints. With visual indication.
  • measure tool: snaps to centre of circle, with visual indication
  • drawing tracks/zones/polygones/lines: snaps to the auxiliary circle, with visual indication
  • used circle with 1mm diameter because of this one disadvantage: the measring snaps not only to the centre of the auxiliary circle, but also to all 4 directions (east,west, north,south) on the circumference of the circle. Therefore I took a “big” diameter to distinguish between centre-snapping and circumference-snapping

Whats missing?

If you only need the Target as auxiliary construction point I think it’s not good to get the targets back (because they are very special items). Instead the general snapping functionality should be improved to suit your requirements. That would be a generic improvement for many usecases, not only for your very specific workflow.

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One other point of adding a footprint and placing it on the PCB in PCBnew. If the tootprint isn’t associated with a schematic symbol - they are frequently deleted when you update the pcb from the schematic. Targets remain!

Footprints added in PCBnew may be deleted if the schematic (Eschemat) is updated and the update is brought into PCBnew. Targets are persistent - the remain even if updates from Eschema are incorporated.

Also Targets as an object were persistent and did not disappear when an update from Eschema to PCBnew were made. If you use a created footprint and add to PCBnew the footprint may be deleted when updates are brought in. Easy to test, select the OSHardware small foot print, put on a board, then update the board from Eschema, the OSH footprint is deleted.

Some foot prints have the center offset and it maybe desirable to have a target that is persistent that is placed at the component that doesn’t match the centroid.

When I’ve laid out boards with ESP12x devices - I mark the exclusion area under the antenna with targets on lower layers – such that I can ensure I’ve can repeat the zones if I need to make some change to the board.

You can mark footprints as “not in schematic” in v8 which prevents them from being removed when you update from schematic.

Even in prior versions, you could accomplish the same by locking a footprint (which for something location critical like a fid you’d probably want to do anyway)

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