@Graeme is correct; the “2” is drafting shorthand that there are 2 locations with 1.3mm diameter pins.
Thanks again Graeme!
It is a BH-32H-1
I haven’t ordered it yet. I wanted to make sure I knew how to make the footprint before I ordered it. I have the Digikey library downloaded. If it is there perhaps I can use that to double check the footprint I make. I just wanted to go through the exercise.
My new schematic isn’t as clean as @Graeme’s, but I think it is better than before and I didn’t have to redo my symbol:
I did include the capacitor on pin 5 as @Jverive suggested.
Here is the footprint for the battery holder:
Now, on to the pcb layout…
Thank you all so much for your help and interest! I am having a blast!
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If you have done this already, my apologies: when designing your own footprint or appropriating a footprint that isn’t conventionally associated with the symbol you are using, it’s worth making sure pin numbers match up. Doubly so when it’s a power component. If the pin numbers on the cell symbol do not show in the schematic editor / eeschema, opening it in the symbol editor should let you identify them.
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Thanks for the tip! I just double checked. Pin 1 is +, so it should match up.
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I fixed the battery cel to read CR2450 and fixed the active low pins thanks to the help from the KiCad 6.0 thread. I just did it right after the last picture was put up.
I am still waiting on my Getting to Blinky board to come in, but my components arrived today. Along with the SMD version of the 7555, I had ordered a through-hole version. I tested out the circuit on a breadboard successfully. I didn’t have the exact resistors or capacitors to get the frequency or duty cycle correct, but it does work:
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Good work!
One thing I find useful is to have SMD to breadboard breakout PCBs. You can buy them, but it is a lot cheaper to just get your own made, and they only take a few minutes to design. It’s useful when you are dealing with SMD only parts, and avoids having to buy DIP packages just for testing. Once you are finished you can easily remove the part with a hot air gun and then use it on your final project.
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Thanks Graeme! I will look into those. I don’t have a hot air gun, but perhaps I should invest in one of those as well?
Tough one…
For desoldering ICs yes. For soldering ICs I prefer my soldering iron and drag soldering. However, you have to watch that you don’t end up with solder balls causing shorts if using a hot air gun.
If using stencils and paste, yes - although an oven would probably be preferable (something I’ve still not invested in - although I mostly get full/part assembled boards now so this rules out stencils).
For small parts - resistors and capacitors (0402/0603/0805+) - maybe. You have to play with the pressure to make sure things don’t blow away. With the right technique, and a pair of good tweezers, it is just as easy to solder them, although the hot air gun probably gives slightly better results. It’s also easier to get the parts straight with a hot air gun since the components move themselves into position, which is really cool to watch and never gets old.
Overall, it’s useful to have, but I wouldn’t say it is essential - at least early on. And, I wouldn’t be inclined to spend too much on one. Mine is really irritatingly noisy (Aoyue 968A+). One of my colleagues has one that is quieter but not as controllable. I can’t emphasise enough how much the noise annoys me. The rubber feet also leave black marks on anything it sits on - which is normally my nice HP power supply.
They are handy for removing stringing on 3D printed parts too. 
Oh and are fantastic for applying heat-shrink tubing.
My blinky boards finally came in. I am going to wait for the magnifying headset I ordered to come in before I solder these together, but I was very happy that my custom footprint for the battery holder seems to fit:
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My family has had a bit of the flu lately (thankfully not COVID), so I haven’t felt much like doing anything; but I decided to take a shot at putting together my blinky board today and I absolutely ruined the first one. I tried to put the 7555 on by putting solder on each of the right side pads and then move the chip into place, but the solder hardened before I got it far enough over. I quickly figured out I didn’t know how to do a chip like this and then I further found out I had no idea how to de-solder something. I ended up ripping the pads off the board trying to de-solder it.
So, one thing at a time. The blinky video course on the site doesn’t seem to have the instruction to solder the board together. I thought I saw such a video on youtube and I am about to go try to look it up. I also checked the skills section, but I don’t have access to many of the courses or skills despite my account level. It shows me logged in and then when I get to the page, it tells me to purchase the correct type of account or log in. So @ChrisGammell, I was wondering if you could help me with my problem accessing content. I am currently using the latest version of Firefox. I will give Chrome a shot, but I generally try to stay off of it these days due to privacy concerns.
I have two more boards and two more 7555’s. If I mess up the next one I will look for instruction on de-soldering before I try that again. 
BTW, @Graeme, I used much less heat this time and it worked fine.
So now I watched the Blinky 4.0 final video and see I should have just done 1 pad to start with. So I did that and the 7555 solder was pretty straight forward otherwise. Unfortunately when I went to get the rest of my parts I realized that I never ordered the 1uF capacitor and the pack of 10000 pF capacitors I did order is nowhere to be found. It appears I will be waiting for Digikey to finish this one up.
Ok, so I forgot to try Chrome before I wrote that response. It does work in Chrome, so I can get what I need. I suppose it is worth a mention that it does not work in Firefox though.
It definitely shows that I went weeks without practicing soldering. The first capacitor was extremely difficult for me, but it got easier as I went through. The R2 was the last 0806 that I put on, and afterward I added the led and the battery holder.
Wow I thought that would get at least one constructive criticism from @Graeme or @Jverive . Did I write something wrong or did everyone get busy all of a sudden? I didn’t expect all of that attention forever, but this went from feeling like a crowded room to an empty field.
Well, I’m proud of it. I also wanted to ask if the CE Header ended up being used very often. I see the potential, but that only exists if there are many boards that use it. It also doesn’t include any differential pairs, so doesn’t that mean the bandwidth is a bit limited? I keep wondering if I misunderstanding something along those lines, because it seems a lot of these small fpga boards also don’t expose differential pairs even though there is support in the fpga itself.
Take silence as good news! Sometimes people wait for a clear invitation to comment as people have different reasons for posting their work (primarily this is your log) and it can be a good convention to withhold comments until it’s clear someone would like to hear from you.
Looks great to me! If you have any isopropyl alcohol and a soft brush (like a worn out toothbrush) a quick sluice and gentle scrub can often remove the flux residue and make the board more aesthetically pleasing and less sticky! Depending on the flux used, you may want to remove it because some are corrosive over the long run and can eat away at traces and joints. But that won’t stop you from having a successful Blinky, so it’s a minor consideration.
Thank you for the response @smerrett79 . I did apply some isopropyl with a cotton swab, but it is pretty evident in the picture that I didn’t do a thorough enough job. It may partially be because I only bought 91% since my two year old wanders near my work bench.
It really is nice to be part of a community like this, especially when you are new like me. I wish this type of community had existed back when I was learning to program.
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