I still don’t see why the use case (pcb without schematic) couldn’t be supported a bit better. For example select pads -> create ad hoc net for them. That wouldn’t require much development effort but would make normal pcb editing possible for no-schematic layouts.
Hi Geof,
I don’t want to change the way you work. It is only out of curiosity: do you draw a schematic on paper before doing the layout?
In my case, having a netlist is a must.
A question of priorities. I am sure if there is a volunteer implementing this then it will be accepted. I however doubt that anyone from the core team would put resources into this. (Reasoning: Wayne made it very clear in nearly every presentation he held that the focus is on getting kicad to compete with tools like altium on a professional basis. I doubt a feature like this will aid in that goal. As companies will most likely always need a schematic for legal reasons.)
Hi Pedro,
I often draw my designs with “pencil & paper” but on very simple things they tend to be “in my head”. I find the biggest pain with most modern PCB software is having to use nets - I want to connect pin1 to pin 2, 3 to 4 then 1 & 4 to ground but can’t because it is a different net (deleted expletive). I just want to connect any part to any part without having to allocate anything to anything. I used to use “Boardmaker” many years ago and it was brilliant BUT it wouldn’t work on Windows (3.1?) so that is when the rot set in and every piece of PCB design software since has offered even more features but become considerably more restrictive for me - and as I said earlier, I’m a bit of a dinosaur.
What part of that doesn’t work? KiCad 5.1 lets you connect pads and traces which don’t have net.
For this you can use WireIt: PCBNEW plugin for adding/cutting/swapping wires in the physical layout
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Hi, Videostar
I was a radio amateur during the 1960s before college. Some years ago I used to insist on laying out pcb’s “on the fly” (not on the gnat or mosquito) meaning that the pcb layout process did not use a link to the schematic. I think I have learned my lesson…the schematic link really does reduce errors. But I have one long term wish which applies to every EDA program I have ever seen…I wish that non polarized capacitors and resistors could be flagged as having interchangeable pins, so it is never necessary to rotate the footprint 180 degrees to make it agree with the schematic. Likewise KiCad will often default label nets as being pin 1 or 2 of a resistor or capacitor, and that is a piece of information which to me is no information.
Maybe the non polarized resistor/capacitor footprint pin numbers would automatically swap according to how the footprint is connected…
You could add that to https://bugs.launchpad.net/kicad/+bug/593944 (or at least ask if this could be done with pin swapping which has been planned for 6.0).
Hi BobZ
I’ve often wondered which end of a “through hole” resistor is “pin 1” (and do they need to be fitted the correct way round for them to work ? )
Sorry, just me still being a bit of a dinosaur. A large number of my designs are very simple, with just a few components, and the circuit is in my head. I just want a single-sided PCB and can design it qicker than I can draw the schematic.
Perhaps I should look for a DOS 6.22 PC and go back to my old version of BoardMaker ?
Seriously though, I do like Kicad - it seems to be the best of the bunch around at the moment. I just wish someone would allow me to design my PCB without resorting to inputting a schematic for which I have no future use.
At the moment I am designing a PCB which will be used for THREE different purposes depending on which parts are fitted (each with its own schematic) - just how do you get around that without laying it out “on the fly” ?
DRC needs to somehow know what should be connected to what. You can work without DRC by switching to highlight collision mode and turning on “allow DRC violations”. This is the easiest option to work without a schematic but well you loose a lot with it.
The way to tell DRC what is connected to what is (right now) done either via the schematic or by some other means that results in a KiCad netlist. Your best option right now is therefore the use of wirelt (linked above)
Fully integrating this into kicad is non trivial as it kind of runs counter to the core workflow. It would need special handling within pcb_new and its file format in a way to be still compatible with using a schematic. (This is one of the core requirements of any new feature addition.) Part of the required backend feature set might come with the pinswap feature that is intended for version 6.
Also consider looking into how much time you really need to draw up a schematic. My guess is that the time needed is much lower than you expect.
The same way as you would on a pcb only implementation. You draw up one single schematic with all the connections in the same manner as you want them on the pcb. The added bonus is that you can include fields for BOM extraction that can tell you which part to use for which version.
In other words: worst case you have a schematic that looks just like the pcb. Best case you have a nicely organized documentation of your pcb that makes it possible for anybody to understand what your system does.
Hi Rene_Poschl
All of my PCBs are now for personal use one-offs so nobody else needs to know what they do. My new “triple” PCB will output either 0-24V analogue or 0-15V PWM both from an unregulated DC power supply or 0-12V PWM from battery power so I need to vary the input supply or the output circuit or both - the PIC in the middle is the same for all three versions. The PCB is still single sided and roughly 75 x 40mm. The problem is that some pads for wire-ended components are shared by different components going to different locations in different versions and some SMD parts are different values. I could have designed the PCB in the time it has taken me to describe it but non-familiarity with schematic drawing would take me for ever.
From those of us that have lived long enough, which is sometimes a couple months, to look at a project and wonder “WTF?” 
Seriously, the schematic is your non-ambiguous notes.
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Hi, Videostar
It sounds like you are describing a pcb with multiple malfunctions. 
Seriously I do not not fully understand what you are describing. IMHO pin numbers on common 2W resistors and most nonpolarized capacitors seems to be bogus. Exception which proves the rule…do you remember “outer foil” on some wound film capacitors?
But I think that one thing I have done is to draw a schematic which includes all of the component locations, even though you would never use all of them at once. There is also the possibility of two parts sharing a pin or hole (or which might otherwise physically interfere) except that you would never use both at the same time.
Thank you eelik.
I had a look at https://bugs.launchpad.net/kicad/+bug/593944. It looks like my thinking is pretty much covered (including your recent addition) and I do not have much new to add?
Hi BobZ
I looked at your link and read it with interest about being able to connect a non-polarised two pin item either way round, basically ignoring pin numbers. If I read the article correctly, it would appear that the main purpose is to allow a neat finished PCB with all of the annotation facing the same way. I did comment earlier that I also etch my own boards and being for personal use I don’t (can’t) screen print them or solder resist them so the need to have the printing “the correct way round” doesn’t apply. Yes, I do remember “outer foil” on capacitors - it was important when used in RF environments for shielding purposes. I also must point out that I hand assemble and hand solder my PCBs including SOIC and smaller “spider” ICs so I can fit my components for my convenience, through hole or SMD.
There is one other subtle and rather esoteric consideration, in addition to orientation of annotations on the silkscreen.
Consider a library that strictly adheres to the standard where “Pin 1” on any footprint is implemented as a square or rectangular pad, while the other pins are circular or oval pads. It may be desirable to have all of the square pads “facing the same way” - e.g., the square pads of all passive parts are closer to the top of the board, or toward the right-hand edge, etc. Admittedly, approximately 90% of this is for visual aesthetics and has absolutely no effect on the electrical performance of the board. However, there are occasions where it’s desirable to have a rounded pad at a particular location because it is easier to route a trace around a rounded pad, than a square pad.
Dale
Silkscreen annotation is independent of the footprint orientation. I think what @Videostar meant was that the text printed onto the resistor itself will be aligned that way as it will depend on the footprint orientation.
If the workflow works for @Videostar (and it seems it has for some of our life times); I am happy that KiCAD fullfill even his way, as it does any other ways.
If I understand him correctly, when he is laying a board with a bunch of components, he put his components as he sees fit and then, he connects them using tracks, if suddenly he notices that a track would be better placed somewhere else, he just deleted the track and connects it any other way. In this case if the schematic has the connections defined (track goes from U1:P1 to R2:P2) he would need to go to the schematic, change the connection as he just occurred to him that it would be better (U1:P1 R5:P1) otherwise PCBNew would not let him connect the pin (which mostly is ok to avoid mistakes. But now in his work flow).
I think everyone does this; I laid out a board with three banks of connectors and a hex inverter IC; while drawing the schematic I connected bank 1 to inverter 1, bank 2 to inverter 2, etc. When routing the board I realized this was making my job harder, so I changed the bank-to-inverter connections in the schematic so that the trace routing would be more logical.
This is the idea for pin and gate swapping. AFAIK pin and gate swapping is in development (or at least on the milestone list) for v6. But, I’m not sure if it is planned to implement PCBNew driven pin/gate swapping or if it will only be done in the schematic.