Hi all!
I want to start by saying that I am totally new to KiCad!
I want to create a footprint or shield for Pokeys 57E.
I have a Pokeys *.step file.
But I don’t really know where to start.
Is there any one that can give a tip of a youtube clip that is suitable for what I want to do.
Contextual Electronics have a video series for V5, but creating a footprint is the same no matter what you use, you have to be able to determine the dimensions.
That looks like it could be a moderately ambitious project; what do you intend it to do?
I don’t know your background to electronic design but I would encourage you to work through a really simple design - perhaps just a couple leds to begin with so you understand the workflow for something straightforward before embarking on something too ambitious.
Hey!
Well, I’m just an electrician. 14 as an electrician, but now I work as a technician at Volvo, not with the cars, with AGVs, automatic guided vehicles, which deliver materials for bodybuilding. I’ve been doing that for 6 years.
I have also been building a flight simulator for the past 12 years.
The project is for the flight simulator, really just to get rid of ugly cables, but also to interface OEM 28V anunciator and dimming them and also hardware solution for dimming leads.
Below I have attached a picture of the first attempt.
Pokeys-57E-print-test.pdf (25.0 KB)
But when I print it, the print does not match the actual Pokeys 57E card. I do not understand why.
I used this guid: generating a kicad footprint from a 3D STEP model - YouTube
To create the foot print. The 3d step file I got from pokeys homepage.
This is the first initial test with step-down buck converters to see if I can match dim mode on led with dim mode on OEM Annunciator: https://youtu.be/6JE7aLqsRYo
Maybe the printing process scales the pcb? You can try printing to a pdf instead and printing to paper using your pdf reader.
Before doing this, place a dimension which shows the length of the pcb. Then when you’ve printed its easy to measure the dimension to make sure it hasn’t been scaled.
How do I place a dimension which shows the length of the pcb?
Hello @JacobW
Draw a couple of lines on a layer ( this is on F Silkscreen).
Place an “origin point” *(red target) on one and your mouse cursor on the other and read the “X” value(bottom centre of screen), or if measuring vertically, the “Y” value.
Origin target is second from bottom on RH list.
In the instance shown on the screen grab X = 107.3150 mm.
Print (including front silk in my example) then measure between the two lines.
But if the size in KiCad is corect. What could be wrong then. If I used 1:1 printing.
I have tested bothe on work and home with a brother printer.
As @albin says, “maybe the printing process scales the PCB”
Holding a ruler up to my screen roughly shows the PCB to be 115mm but your underneath drawing is 110mm; so you need a scale factor of 115 /110 = 1.045 to 1 instead of 1 to 1.
The exact scale factor you need must be determined by you as you have both the board and the drawing.
You could do as jmk said, but my preferred way is to add a dimension using the dimension tool. See the documentation:
https://docs.kicad.org/6.0/en/pcbnew/pcbnew.html#dimensions
If you get to a point where you can measure the dimension on the paper to be correct using a ruler, than the paper can be used for validation.
(I printed to PDF using windows direct from KiCad).
When opening the PDF on the computer att work, the card I made is bigger then the actual card when holding Pokeys card infront of the screen.
But when I cange the view to 98% in PDF reader all holes match perfect.
So the questions is:
I have matched the pin holes to the drawing in Pokeys manual. Witch is 2.54 betwen them.
So in my world I think it is corect. But the printer some how cange the size.
I can gladly send the files her if someon want to have look. But when I saved the project a lot of files whent missing and therfor I cant open the file.
Bothe the footprint and symbole I think disaperd, or it have to do with using KiCad 6 at home and on work I only have KiCad 5.1
Her is the pokeys manual where all messuers come from, or the step file on ther homepage I used:
Size from manual:
Her is the project I made:
Pokeys 57E-2022-02-13.zip (53.1 KB)
So I write: 1.045:1 in custom size when Printing?
But why is it getting wrong I want to konw?
Hello @JacobW
My measurements were very rough as all I did was hold a ruler up against my computer screen.
You need to compare the board size to the drawing size and use that difference as a printing scale to get an accurate result.
My comment with 1.045 to 1 was just an example of what you need to do yourself. Only you have the correct sizes.
But how do I calculate when I get that done?
Lets say I add ruler on diferant parts and holes to a origin. Then Print and discover that the ruler is not corect and the holes do not match.
Like how it is for me now. The acual Pokeys card is: 83 mm long and the drawing in the manual say: 83 mm
My PCB in KiCad is 83 mm but the paper print becomes 79,5 mm long.
How do I then adapt/calculate scaling for printer?
Have you tried printing from the plot menu? That should be to scale if you are just checking size and such.
Thanks.
Will test.
But do anymore know why this happens?
Not really. Perhaps something in the chain tries to get the print to “fit the page”? I have printed to paper sometimes without this problem, but I believe I’ve printed to pdf first and I’ve been careful to remove all scaling in all settings.
