Track connections

Some advice for a newbie please.
I cannot make some track connections in this example. Square pad 1 to Round pad 1 AND track end to Round pad 5.
I have checked the pad properties and their clearance settings are all set at 0mm.
What is stopping me?

Do you have a schematic for this design?
Am I seeing a large clearance on square pin 1?

Are all your components on a suitable grid?

The image isn’t accurate enough to read the text but to me it looks like each pad has its own net. Which tells me that either there’s no schematic or it hasn’t been used properly.

Thanks for the replies.
Yes it was built from a schematic, but being first I have ever done I could have made a mistake.

It does look like one but I cannot see how to delete/zero it.

The components, with the exception of MuffsyPSU, were taken from the standard library then edited to match my components.

I have a 0.5mm grid for the pcb layout.

How can I check and correct it?

Sorry, I should have typed:
Are all your components on the same suitable grid?

When moving your mouse, does it always land in the centre of every pad of every footprint?

The cursor seems to snap to the pad centres and their XY positions are all x.5 mm, so I think so.
Fiddling (!) around a bit more it looks like the pads and tracks are not on the same net, not sure how or why that happened. Since my layout is so simple, is there a way to globally set them to the same net ?

You need to post better screenshots.
The text in your screenshots is not readable.

Pay attention to what eelik wrote.
The “square pad 1” and the “Round pad 1” are not in the same net, and KiCad therefore does not know you want to connect these together, and it “helps” you by preventing you from making faulty connections.

I am not sure what this is:

But there are no wires attached to it. and therefore KiCad dos not make the connection either.

A visual reminder of the PSU output connection, not part of the KiCad schematic but it was something for me to keep in mind. I will remove it.
Screenshots: OK. I have to Photoshop them all as they are too large from my High res screen, I’ll alter my settings.

I haven’t got my head around the concept of ‘net’. Should I change them all to the same one, and if so, what is the best way?

I don’t see that connection at schematic.
I suppose square pad 1 is at schematic on the left and is connected to pad 2 of transformer so why you think of connecting it to pad 1.

The schematic has the terminal numbers from the original component, the pcb layout has its terminal numbers from editing them inline with my actual components. I have looked to see if I could re-number the schematic without success, could this be one of my problems?

I once more don’t understand what “editing inline with components” means.
What you are doing (and why) after updating pcb according to schematic?
Perhaps I don’t know something but I never had any need to edit any pin numbers at PCB. Having right pin numbers is the task for symbols and footprints before schematic and pcb are started to be designed.
Simplifying the process after updating pcb from schematic I only move footprints to right positions and make connections using tracks.

Sorry I’m not clear.
Using the transformer as an example.
I chose the nearest component I could find in the library and placed it in the Schematic.
I then edited its footprint so it matched my actual component. Number of pins and their numbers.
That footprint was then used on the PCB.
I hope that makes sense.

Yes, it makes sense, but if you did it as you described then at PCB you will have the same pin numbers as at the schematic, but you don’t have. Don’t you see it?
I don’t think you have right pin numbers at schematic and right pin numbers in footprint?
If so then tell me why you have at schematic connector pin 1 connected to transformer pin 2 but you are asking about connecting that pin 1 to transformer pin 1 and it looks you don’t see any problem in asking such question.

How does KiCad know which symbol pin represents which pad of the footprint? may be good to read.

Thanks for your help.
I am afraid that now you are not clear !

So the footprint was numbered like the actual component, the schematic still has its original, incorrect numbers.

I think I do that is why I asked this:

It is working backwards to the schematic from the footprint that seems to be my problem.
But then again there is also the question of ‘nets’… but one step at a time.

Here is what I don’t understand.
KiCad uses pin numbers from schematic and looks for the same pin number in footprint. So if your symbol at schematic is connected with your footprint then connections made on PCB are based on that numbers - they just can’t be different at schematic and at PCB as it is the way to establish which pin is connected with which.

Thanks eelik, I have quickly read it and it confirms I have ‘crossed’ pin/pad numbers.
Fixing it is my problem

The concept of a net is very fundamental in KiCad (and any other PCB design software)

A net is basically everything connected by copper, and a list of them is called a netlist.
It is possible to generate a netlist as a separate file, but these day’s the netlist is communicated directly between Eeschema and Pcbnew.

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Thanks Paul,
So for a pad and track to be connected they must be in the same net?
But could be on a different Net to the other side of a component.
Simple example Pad > Track > Pad > Resistor > Pad > Track

Have I got that right?