Start a new pcb without schematic

Dear, I am sure that this was asked before but i cant find the answer of how to do. I am trying to start to use kicad as main PCB program, but allways i get stuck and i cant progress.

Normally when i do a PCB design i start from available space to work, this say: i draw the PCB perimeter, fixation holes etc etc. Why? because i use an existent plastic box, and i do the design to improve manufacturing time.

Question 1) How i can draw the PCB outline ? for example a triangle of 6 cm of each side. Without use the ground plane?
Question 2) How i can put an central hole of 3.25mm (is not a component and have no footprint?
Question 3) How i can put a arbitrary pad in the pcb?

Best Regards, and thanks in advance.

Kicad is not a drawing application but Menu Place -Line always allows to draw anything. If this is PCB outline or anything else depends from your layer setup and later Gerber processing. For holes try Place-Via what is possible without net assignment. Anyway load a netlist and then place components is more useful for any circuit connections. Otherwhile you can consider any mechanical CAD or DXF editor like some users do for RF designs

KiCad is not well suited for working without schematics. At least not if you need to make connections between pads. And more importantly not if you want to use copper zones.

I am of the opinion that any board that can be created without a schematic has its schematic created in a very short amount of time. (the benefits of working with schematic outweigh the time needed to create them.)

Zones have the purpose of filling an area with copper not to define the outline.
Board outlines are defined by using graphical items (lines, circles or arcs) on the edge cuts layer.

Use a footprint with a single pad. Have a look at the mounting hole library

Again footprints are your friends. Not sure what you try to do but in most cases you will want to have more than one pad with precise distances between each other. This is best done inside a footprint as you can move them together later if you need to.

But even single pad footprints are a posibility.

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Thanks for the answer to both.
Rene, i will try your suggest.

I don’t think that DXF (like qcad) become useful. For the moment i am using autotrax ( under dosemu) or protel (under wine) and i generate the gerbers files for the PCB maker.

Now i am searching for a more modern PCB designer software to do the work Better if is OpenSource.

Out of respect for you, I think you both deserve an explanation. And that my requirement is not a whim.
The electronic argentinian market is very small, 100pcs is considered a good “production” level. A sale of 1000pcs is like reach the heaven for many small companys.
This force 2 things:
One the product must be like any proffesional international brand
Two, the sales level dont allow create one plastic custom box.

This force to search standarized plastic boxes and the design must be fit in the previous place even irregular forms. (Answered question 1)

As the quantity are lower when i do a design, i add as many components as fit in the place for future and possibles usages. So the same board can be used in 3 o 4 different project changing some components and using other unused components.
For example project A use Q1, and a C1, but project B dont use Q1 and require a resistor into C1 place.

About question 3: Sometimes i put a test point, or optional wire solder ( even surface mount)
Again, thanks and best regards to all

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I think you should be able to create a PCB with pcbnew that just has the outline in the Edge Cuts, a hole and a pad, and then append this template board to the layout generated from eeschema to get a board with a circuit and standard outline and hole. Not sure if you can join the pad to the other circuit but you could put the pad in the circuit and position it where you want. The append board operation is only available when pcbnew is run on its own, not from a project. I’ve used it to panelise boards, but not in the way envisaged here, so let us know how it goes.

This could help…

Say you have a Box and know the dimensions.
You’ve sketched the PCB shape so it fits in the box.
It’s going to sit on four standoff’s and screwed down
(you know the Hole locations).

Option 1:
Sketch the PCB shape in a CAD or Drawing program that can export DXF.
Import the DXF into KiCad.

Option 2:
Draw the PCB shape in Kicad, include the screw holes.

Option 3:
A combination of 1 & 2, above.

I threw together a box and sketched the PCB perimeter with some dimensions (done in FreeCad but, Inkscape would work, too). I included only two holes.
Exported as DXF.
Imported into KiCad.
Drew one of the missing holes (lower right corner). Did not fuss with accuracy but easy enough to do.

Result is the desired shape with the three holes… Shown using the 3D-View in KiCad.

Summary, Though not a CAD or Drawing program, KiCad can do much of the simple PCB related cad stuff…

Option 4: use freecad with stepup for handling board outlines. See Kicad StepUp: The Sketcher for Getting to Blinky or even to manage component placement Kicad StepUp: a Seamless ECAD/MCAD PCB Data Integration

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Option 5: do as many of us do when making an Arduino shield. There are good examples in the official Module.pretty lib.

Draw the pcb outline with the footprint editor. In order to make the outline you can use any of the methods already shown. If the outline is not too difficult the Kicad graphic lines work fine.

Add the holes you need as through hole pads. Then save it

You will get a footprint of the outline+mounting holes. This footprint can be added with the “Add footprints” command in any new layout.

Dear All:
I perform my first draw ( unfunctional but usefull to learn to draw)
The border, this was the best solution.

[quote=“Rene_Poschl, post:3, topic:20800”]
Board outlines are defined by using graphical items (lines, circles or arcs) on the edge cuts layer.

About my question 3:
I do use the predefined hole footprint. But take the pads as component with a footprint cause an unwanted reference number. I think that in sooner or later the pad funcionality must be added.

Now i have other question the ( 4#. jejej)
4) If for example i put a DIP 8. I can edit hole size, pad form, pad size, layer of pertenence for ONE SINGLE pad of the component?
Explanation: When i use some components with multipad, for example dip 8. I use the pads as bigger that i can, but when i need pass one trace in the middle of 2 pins i do more smaller pad ( in the X axis, and even increasing Y axis).
Again thanks to all

Always be aware of your own biases. Just because you assume the best way to solve your problem is by using a particular workflow does not mean that anybody else would choose the same route. It does not even mean it is the most efficient or powerful option available to solve your problem.

I would argue that you would benefit greatly by creating a schematic for your board. Not just because this would add a lot of power to the layout program (DRC really needs a schematic, so do copper zones). But also because future you will be thankful if there is proper documentation of the function of your boards (your customers might also thank you). It also allows you to more easily collaborate with others possibly opening up the route to even more customers.

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Dear Rene:
I never said that my way to do the things is the best way. I am sure that i am failed explain my workflow or i fail writing because the english is not my native language. I never try to force to anyone to use or change anythingt, and my apologyze for any misunderstanding. But i still feel that pad function could be a great function for the kicad and the missing is a weakness. Of course i can be wrong

I dind’t have a complete schematic is true, but this dont say that my projects are undocumented. Normally i get manuals with 30~50 pages explaning block by block the entire circuit, formulas, and why a component was choosen, wich was the discarded alternatives options and why was discarded. Even i have documented the changes with the previous releases and futures changes.
For example in the image you see 6 different way of assemble the same PCB.

I know that is not the best way, but is not the worst. I repeat my apologyze if someone read as i try force to anyone to change their way to work.

Any idea about how edit one pad that is part of one component( Question 4 )?

Just editing a single pad of the component. Simple enough.

Select the pad, press “e” and change whatever you want of that individual pad.

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The pad number can be deleted with the footprint editor.
The pad number is the way kicad has to relate a pin of the symbol with a pad of the footprint. In your case it is not needed since you don’t use the schematic.

We are those trying to force you to use the schematic :joy:
Maybe because our experience with Kicad has taught us that working with schematics saves a lot of headaches in the long (and not too long) run.

I think you misunderstood. It is not the pad number that @schlabs is trying to “remove” but the reference designator (example R1) that is on the silk screen.

And that one can be hidden already in the library but also in the layout editor (pcbnew). In both cases via the properties dialog of the reference field.

That was my first guess, but I found it quite obvious

Dear people,
About the workflow, i do projects for more than 30 years and the mistakes level is very very low. Please trust in me because i know the reality of the things here.
For example a prototype PCB require u$s 200 (50% of on salary), and if i want add a stencil are u$s 600 more. I know that most people in the world can do the same paying only u$s 2 on and 9 if pay the stencil, here we have limited the dollar access (up to 200), a maximum of 5 packages/years, and a special tax to dollar purchase of 30%. If i tell to a customer u$s 800 for a prototype or 10pcs he run away more faster than Forrest Gump.
My last draw can use multiple possible voltage regulator so the project can work with: 78l05, 78l033, mcp1702, ld1117, ht7463 or whatever that i found on distributor. One 47uF cap have 3 footprint ( thru hole, 1206 and 0805) etc etc. The project must be do with the material that i can found. In 2014 i spend one week trying to purchase fuses ( yes the common fuses 20x5mm 6A). So, please don’t judge to me and my special workflow.

Returning to the center of the question 4:
Making double click i can edit a pad into sot23, doing double click appear pad menu. Pressing E key show a different menu and i didnt find how reach the same point as double click.
Double click dont work on component-pad.

Of course we don’t judge you. Cada maestrillo tiene su librillo (every teacher has his book).

Double click and “e” show the same menu. But sometimes I agree it is difficult to select a single pad or the whole footprint. One can think the pad is selected and instead it is the footprint what got selected. I use to zoom in and select the pad/footprint carefully.

As one schematic symbol can have only one footprint, sometimes I have made a custom footprint with all the possibilities. Then I have mounted one part or another. It is more or less what you do but made into the footprint instead of directly into the layout.

jejej i am not a martian jejeje. I will try that you say.

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