KiCad 5 (Part 12) Creating new Footprints

[Music] [Applause] hey John here so I got a bunch of these switches sitting around my my shop from an old project and I'd like to use them I don't have a footprint in kicad that matches this which is drawn up in this corner here first of August the switch is a double pole double throw switch it's a momentary contact you can see there's a spring in the switch and the mechanical drawing its relaxed position is drawn here pins two and five of the pivot and it goes between you know two and one or two and three depending on how I push it as well as five and four and five and six here is the drawing of what the PCB layout for the footprint supposed to look like two point five zero on Center in both dimensions and this means it is a one millimeter drill hole that you need for the leads so how do we do this all right fire up kicad let's make a new project I don't want to mess with my existing one so I'll create another test project 20 45 - test or something alright let's go ahead and take a quick look at the symbols that are already in here remember I loaded the digi-key library and it turns out there is a double pole double throw switch not a relay right there there's a switch in the library already or so there's a nice schematic symbol for it and this matches this drawing right down here the tube B goes between 1 & 3 & 5 goes between 4 & 6 it's drawn here in its relaxed position that's pretty nice I don't have to you know draw another symbol this of course is for a different part that is a different footprint I can go in here and delete all the digit key fields and update them with what I want if I would like to normally I would I'll leave that for you the footprint I know was wrong this is a surface mount part and the part from mine is actually this if you search for that in digit key you can buy one of these for yourself pasted in here and okay so now I've modified you know use this symbol I didn't modify the symbol modified by schematic to be useful with the existing symbol now I'd like to be able to pick a footprint but I don't have one yet and I don't even have a library so let's create a new library and put that footprint in there this is designed a little bit different than the symbol library let's look and see what we're going before we get there this is the directory within which I put my John's basement symbol library right in here I'll also put a John's basement footprint library now unlike the symbol library where you have this one pair of files here that hold all the symbols this is a backup file that get even ignores the footprint JB footprint library is it going to be a directory and within which there will be a separate file for every single footprint so it's a little different philosophy clearly written by different people then did the symbol editor there's also a chicken-and-egg problem you can't really create an empty library with this tool technically it's just a directory I could just make Deer a directory and theoretically there is my library and actually you could do that except there's a note somewhere about some versions of kicad old ones presumably that will crash if you add a footprint library that doesn't have any footprints in it so hmm alright so do it in the right order the saving and creating libraries is blurred out right now because it wants you to have a footprint to put in it in order to create it so let's create a footprint the name of the footprint will be the name of the part that I'm making it for zoom out here now doesn't have anything really going on yet but otherwise it's a footprint logically now these are lit up so I can say create a new library and save the current footprint in there I don't want to put it in my existing project so I'm going to navigate over to I keep my library's for John's basement and I'm gonna say good pick this directory where I put the other stuff open now in there I'm gonna say what I want to call it JB footprint I got JB symbol JB footprint indle added dot pretty if I don't put it in there myself now I hit okay all right so what happened over here right this one as before and here's what it is after it created this directory and in that directory is this footprint and that's what I called my first footprint and as I add more to this there'll be more files in there so that's all there is to it to creating a footprint library with a footprint in it now let's make this footprint useful and let's make sure that the footprint library is added to this list here and it's not unlike the symbol library which automatically added itself to the foot to its library table when you created it footprints don't do that another interesting feature of footprint libraries okay so let's go ahead and find it in here it's in here and it is in this directory right there okay it okay now I've added it to the table manually again where the symbol did or automatically the footprint has to be done manually so now I've added this to the global project table so any my project can use it so let's get back to the task at hand now that I have a library made and it has a stub project in here for a footprint let's make this into a real footprint what do I do get this over here so I can sort of see it while I'm editing over here at the same time sort of alright so what do we really need to know here the two five zero spacing in the one millimeter hole is pretty straightforward this is an easy one all right first thing we need is the grid look at what my grid is set to I could set my grid to two five zero but if I did that and I placed this is how you put a pad down just like on a PC board you're putting you know parts and wires and down here you're gonna put an individual pad down if I snap the grid to two five zero what happens is I have to put one row of holes here and another roll up here what I'd like to do is Center the part on this blue crosshair I can't do that in here it would be nice if had a grid that was a 1.25 but I don't have that ability so the closest thing I have is gonna be this a multiple of 0.25 and then I'll have to just skip multiple grid marks that's okay so let's look at how to put these pants down here because I want to be 2 5 0 on Center if you put the pad right in the crosshair and you look at your dimensions I'm gonna down here the X&Y rather okay you can see where you are in the space of this thing so I want to be negative 1 point 2 5 which is right here and there's 3 of them so this is gonna be 2 5 0 2 there alright so my X is 2 5 0 and my Y is 1 2 5 that's where I want this pad to go all right I click it and it's already ready to do pad 2 which is gonna go over here but before I do pad to I just hit escape let's edit pad 1 and see what's going on here the hole size is wrong I'm gonna set the hole size now because what happens is as I go along and placing more pads I don't want to have to edit every one of them so in here if I say make this a 1 millimeter hole I want to make this to be about a 1.7 in order for this annular ring to be thick enough to be useful I happen to know that the regular and many footprints inside key can't use 1 millimeter holes and 1.7 for the pad around the hole that's a pretty reasonable size these thingies up here choose when they're honest oval one a rectangular one for pin one it would be nice to have a rectangular shape so that's fine I'll go ahead and do that now if I place another pin the defaults will copy the one that I just sent right there I'm gonna click pin to and I'm gonna hit escape I'm gonna select it and hit E now I'm gonna go back to a circular pad and I'm gonna place more circular pads now remember I'm at 1 to 5 and now I'm at negative 2 5 0 for pin 3 alright now in the drawing this is where pin 6 goes so a number pin 4 had 4 needs to go over here he has to be at 2 5 0 and this time it'll be negative 1 to 5 all right that's what I'm looking at and the X&Y coordinates so here's pin 5 should be 0 in one negative 1 to 5 in pin 6 is negative 2 point 5 and negative 1 to 5 those are the pads for this part I'm going to ctrl s to save it and it wants to know where to put it I don't know why it managed to forget but I'm gonna put it in the JB footprint library that just created down there and I'm gonna hit OK presumably if I hit save again ctrl s atleast it remembers where it's supposed to go so I don't have to do that every time alright so there's a little different philosophy again then the symbol editor but certainly manageable so my footprint holes look pretty darn good in fact inside here just like a pc board I can hit all three I can look at the 3d view of this thing which is not particularly interesting there's no surprise there that darn gall-darn that was lucky it looks pretty much like it's supposed to look now how do you get the other stuff in there I'm not gonna mess with 3d shapes just like the digi-key library doesn't have them I don't really want to mess with them myself either but I would like to put down like the courtyard or some kind of thing on the PC board to let me know on a silk screen how big it is when I put down other parts around this thing I don't have that you know I don't accidentally put a resistor so close that it's like underneath you know the edge of the switch or something over here so what am I gonna do I'm gonna note that it's fourteen point seven by seven point three I'd like to draw this rectangle but as you can see down here it's not exactly centered so how am I gonna do all this it gives you various dimensions this here is six point two millimeters to the right of pin one is where the face of this thing is so let's look down here just like in the PC board if you go over here and I'm over this pin one you'll notice this there's a DX entity whine here and there's an x and a y over there if I hover right over pin one so at the two point five in the one point two five and I hit the space key what just happened right there is these DX and dy values just became zeroes while the x and y still tell you the absolute coordinate from the origin so now I can go to the right from here your six point whatever okay so I'm at 6.20 I'm on a 2.5 or 0.25 rather grid spacing so and that's fine I can go over here at six point two five and I can draw a line oops that represents the front of this switch from that line I can then go to the left fourteen point seven five because I'm at 0.25 grid and I can then draw the back and so on around like this all right so let's go ahead and do that zoom out a little bit we know we've zeroed the the DX paying one here so if I come over here to six point two five that's about where the front of the housing will end so let's go ahead and grab oops let's get on the front silks okay I already did that grad a graphic line from over here remember it's seven point three wide from end to end this is on Center so this is really what three point five would be half of seven so this is three point six five half of this so I'm gonna come over here to my 6.25 and then I'm gonna come down here to the the Y position not the dy I'm on the Y position now two three point six five well seven five will do and I'm gonna click right there and I'm going to come up here to a positive Y value of three point two five all right so this is where the front of that switch is gonna be if I actually go back here and I hit the spacebar again notice the DX and dy just went back to zero zero so if I move it to the left now and oops I'm stuck drawing this line let me go ahead and end it right here I'm gonna hit escape to get this darn thing on the screen fourteen point seven zero did I accidentally end up no I am at 15 points something here so it would be nice for it to end right there I this is minus fourteen point seven five from where I hit the spacebar so I can grab this by clicking on it and just drag it over to here fourteen point seven five is basically close enough now I've got these two sides this should be looking pretty good here I'm a dy from here okay he's seven away remember this is seven point three so I probably messed up why am I wrong here this should be down here I'm at three point seven five down this one is three point two five up so I didn't do it this one here right this one needs to go up so I'm gonna grab this as you saw me ctrl Z to undo it click it once to grab it now click here and drag it up and I'm going up and I'm looking at the Y I'm at negative three five this is negative three seven five all right that's where that should have gone I select this I hover over the white dot and I can drag the end up to there now when I'm down here what do I got here my dy is one point oh I'm still not quite right my why is 375 why is this still 375 375 oh because and I need to hit the spacebar up here again because I relocated this point come down here and now I'm looking good at 7.5 which is close enough to this thing is it still centered 375 375 yeah fine with the grid set to this resolution that's what I'm going to get so now I can just simply go over here and I think I'll try an eyeball this that looks about right and then I made this guy over there and hit escape to end it save okay now I have a silkscreen line around where the housing of this which would be now I'd like to go ahead and draw something about this here I can put that in the courtyard or something like that which is fine let's go ahead and draw cart yard this thing is bigger than the switch anyway so let's draw the courtyard and the same as the the silkscreen like this all right and hit escape and then out the front I want to draw this snout of this thing right so where the heck is that all about it goes over ten and a half from the face of this thing all right so what am I gonna do I'm gonna zoom in here it's ten and a half how wide is it it's 2.8 mmm then we can call that 2.75 if we want to or 3.0 it's even easier that means we could go up one and a half and down one and a half so I'm gonna go right here I'm gonna get the spacebar and rezero my DX and dy again I'm still in the courtyard I'll grab my polyline from here I'm gonna go up what I say I'm gonna do we're gonna just draw it at 3 instead of 2.8 cuz it comes out easier so I'm gonna go up one and a half right here click it my DX is zero I can come over here ten and a half I'm alone on a space if you hit the edges that it starts scrolling right so I'm looking at the DX right now until I get to ten and a half left click come down here I said remember my I'm gonna draw this too from up here it's at one and a half in and why negative one half I'm gonna come down here so that I'm at positive one half left click bring it back to here left click hit escape and now I'm done save done so this is good enough for my footprint save did I do that right okay and and I can now get out of the editor here I can bury this behind here open up the schematic it eat edit this go on the footprint browse footprints keep in mind that I already added this it'll be on the bottom of your list there's my one and only footprint okay save yeah generate a netlist we forgot to annotate that's fine the one only part in here open up your PC board reading yourself a nice netlist hit close and there you've got yourself your wonderful footprint and again there's your 3d view right there so there you got it you're done there's your footprint start you know drawing up some traces and hook it up in a schematic to whatever you're gonna do and this is a pretty useless trace but you know what I mean so once you draw it in your head you're done you ship this baby out to ash Park or wherever you want to go start making your boards so let me know what you think about this series in the comments I'd love to hear from you thanks for watching [Music]

Channel: John's Basement

Views: 11,748

Keywords: kicad5, kicad, schematic, PCB, EDA, maker

Id: Rdm5lS_sYsc

Length: 19min 46sec (1186 seconds)

Published: Tue Mar 19 2019