I have Socket Kits put together now. Happy to send you one! That goes for anyone else beta testing too. Let me know if you'd like a Socket Kit and/or another Breakout kit along with it.
This is very sound advice. What seems to work is to tape everything down really well, so nothing moves at all, and alignment is good. I've been "backing off" the flex cable by about 1 mm so I can clearly see the very tip of the pins.
Yes, this is a TI datasheet fail.
Short answer: Pin 1 is on the side with the long bar. Match that to the dot on the PCB.
Long answer: I figured this out using the datasheet, but not because the markings on the chip are documented. That would make too much sense (sarcasm). What is documented, is the orientation of the chip in the tape relative to the sprocket holes, and then the "quadrant" of the chip that contains pin 1. So if you look back at the chip before taking it out of the cut tape packaging, you can deduce it from that. And yes, the markings are super faint, so you really do need a loupe to see them. Overall, pretty annoying.
I've noticed this too. I figured, oh, this is a big component, so I don't really need to secure it. Nope! It slid around all over the place. So tape the thing down and use plenty of flux. It has a lot of surface area to heat up, so keep the iron on there until it flows.
A note about this component: The ones in the beta kits are genuine MPD parts. I just received some generic Chinese version of these holders, and believe it or not, they're better, because they have a little hole in the center of each solder tab. The hole makes it easier to heat up, easier to keep in place, and easier for the solder to flow around it and adhere. I'm sticking with the cheap Chinese ones.
Yes, flux is a must. I use those "no clean" flux pens. I'm partial to the MG Chemicals ones, mostly because their tips are way more durable than the others. I don't think Digi-Key stocks them, but Amazon (ugh) does.
EDIT: Yup, out of stock at Digi-Key.
Mouser does have some:
https://www.mouser.com/ProductDetail/MG-Chemicals/836-P?qs=CEmwANdt9pu6EPsg7HKqcA==
More expensive on Amazon:
https://www.amazon.com/MG-Chemicals-Clean-Flux-Pen/dp/B01ELUI19Q
I've gotten in the habit of just taping boards to my work surface instead of using a special holder. I use blue painters tape. No residue. And it smells kind of nice when you accidentally burn it.
Wow, I didn't even realize the SD card even had a removable cover. I'm gonna have to check that out. This part (the SD socket) is likely to be the one "brand name" part to survive. The generic ones I ordered are good quality, but they're about 1 mm taller, making the Micro USB jack just barely inaccessible when the Teensy isn't socketed. The Amphenol ones are significantly slimmer and leave just enough clearance for a normal USB cable.
They certainly are small. Happy to send you another one, just let me know.
This is getting a bit long, so I'll post my further replies in a new comment.