I’ll try not to accidentally snort them. 
Edit: or intentionally.
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Too late to change it now, but I usually recommend standardising on 0603 components, unless there’s good reason.
Yes, you’ll be able to hand place them for reflow though 
Rework will also be a little more challenging, but do-able. Especially if have a miniature-thing pro like Janet around
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@mike Happy to make a solder stencil for you. Also would love to put a board together if there are any available. Can pay for parts
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That’d be awesome; I’m covering parts and boards for my beta testers
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Status says back from fab expected on the 29th so expect another week for shipping
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I’ve started to replace the smaller ones with 0603 but I’ll only be able to replace them if I remove some of the 0R jumpers.
I guess after we validate the board, some of those 0R’s should be easy to get rid of.
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Shipped! Go OSHPark! That was fast!
I think this board should be red. Love it! Looks awesome.
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Anyone up for a beta build on Wednesday the 11th? There’s a slight chance that the LED board will be in too, but I’m not holding my breath.
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Okay, Wednesday the 11th it is. Whoever can come, I’ll be supplying all the boards and parts. If you have a 1 cell lithium ion battery (I have 2 of them) please bring it along if you want to try it out (bring the datasheet for the battery so we can set the right values).
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Just a heads up, it looks like there’s a bodge we’ll have to do at minimum.
Two of the resistors that set the charge rate and limit rate I didn’t purchase for the battery I have, so we’ll need to bodge two resistors to larger format (probably just do a thin wire to a through-hole resisotor. While not a board error, it is certainly a logistics error.
Just wanted to point that out since I discovered it, and it kinda sets the tone for tomorrow night. If we walk away with 1 working board, and a list of steps to perform to get them all working, I’ll be happy.
I still think the circuit itself is fine, I just need to put in another order for some specific resistor values. If you are bringing a battery, please make sure to bring the Datasheet with the maximum fast charge current and the cutoff current.
Luke mentioned there are 0402’s likely at the space, yay! Maybe no problems after all!
I’ve got about 10 lioon 18650 cells I can bring too.
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Dues “setting the right values” mean choosing resistors, or something softer?
Haha, yeah, choosing resistors.
The controller chip uses two resistors to set the fast charge rate and the end current condition.
Here’s my handy guide on another board that uses the same circuit:
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Thank you everyone for coming out last night. It was a real good time!
Special extra thanks to @Majicj for putting up with my crazy, being the real teacher to us all, and making us the solder templates on the laser cutter. He worked with a really crummy file I gave him, spent lots of effort cleaning it up, his own material and time, and I cannot thank him enough. He’s is the real hero of last night.
It sounds like we got a few boards working, and, very interestingly, we walked away with a lot of learning.
Primarily, 0402’s are a pain in the butt, and don’t use much solder paste on the thermal pads. Make text bigger, get rid of the 0R jumpers that don’t have any purpose now that we’ve debugged it, and a few other little layout items.
Also, make sure you order ALL the parts facepalm and I’ve learned a thing or two about how a build BOM and assembly guide SHOULD go (aka, nothing like what I did).
I’m going to work tonight to try to get a revision that is easier to build, fewer part count, and ideally has a higher yield.
Thanks for all the lessons! It was great.
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Very cool project @mike! It’s been fun watching you develop it. I am learning something from you and look forward to doing a build on the next revision!
Ohh I have a new appreciation for 0402s. 
They are possible to do but …