4 ms·

It's also missing Z-tape. Double sided sticky tape that only electrically conducts in the z-axis. Great for where you would traditionally solder a component to

by Fordec 4y ago

It's also missing Z-tape. Double sided sticky tape that only electrically conducts in the z-axis. Great for where you would traditionally solder a component to a PCB but you don't want it to be a permanent fixture. https://www.3m.com/3M/en_US/p/d/b10167835/ https://www.3m.com/3M/en_US/p/d/b10167835/

zarzavat 4y ago
What is the canonical coordinate system of a roll of tape?
- HPsquared 4y ago
  Rolled or unrolled?
  - kyleShropshire 4y ago
    A small wad, after getting stuck to itself and an unsuccessful attempt at separating it, that is now stuck to one of your fingers no matter how hard you attempt to flick it off.
  - dotancohen 4y ago
    You have to know these things when you are a king.
- rahimiali 4y ago
  Unroll the tape on your right index finger, starting from where your thumb meets your index. That's the origin. Your thumb points along the positive Z direction. Your index points along y, and x is your middle finger points along x.
nocterro 4y ago
Fascinating! Seems like that could be an effective way for hobbyists to attach BGA components to a PCB without a reflow oven - any idea if that’s been tried?
- gregallan 4y ago
  From the datasheet linked there, it looks like the minimum recommended spacing to ensure electrical isolation between adjacent conductors is 15 mil (0.4mm). In an example I found here [1], the pitch between BGA pins is 0.5 mm to 1.0 mm, with pad sizes roughly half of the pitch. So it looks like for the larger pitches, it might just work. 3M also says they'll do custom tape with better isolation, but that might just be more expensive than a reflow oven. [1] https://www.nxp.com/docs/en/application-note/AN10778.pdf https://www.nxp.com/docs/en/application-note/AN10778.pdf
- thrtythreeforty 4y ago
  It has been tried and doesn't work very well, even for low-density pinouts: https://tomverbeure.github.io/2019/11/21/Z-tape.html https://tomverbeure.github.io/2019/11/21/Z-tape.html

by Fordec 4y ago

zarzavat 4y ago

What is the canonical coordinate system of a roll of tape?

HPsquared 4y ago
Rolled or unrolled?
- kyleShropshire 4y ago
  A small wad, after getting stuck to itself and an unsuccessful attempt at separating it, that is now stuck to one of your fingers no matter how hard you attempt to flick it off.
- dotancohen 4y ago
  You have to know these things when you are a king.
rahimiali 4y ago
Unroll the tape on your right index finger, starting from where your thumb meets your index. That's the origin. Your thumb points along the positive Z direction. Your index points along y, and x is your middle finger points along x.

nocterro 4y ago

Fascinating! Seems like that could be an effective way for hobbyists to attach BGA components to a PCB without a reflow oven - any idea if that’s been tried?

gregallan 4y ago
From the datasheet linked there, it looks like the minimum recommended spacing to ensure electrical isolation between adjacent conductors is 15 mil (0.4mm). In an example I found here [1], the pitch between BGA pins is 0.5 mm to 1.0 mm, with pad sizes roughly half of the pitch. So it looks like for the larger pitches, it might just work. 3M also says they'll do custom tape with better isolation, but that might just be more expensive than a reflow oven. [1] https://www.nxp.com/docs/en/application-note/AN10778.pdf https://www.nxp.com/docs/en/application-note/AN10778.pdf
thrtythreeforty 4y ago
It has been tried and doesn't work very well, even for low-density pinouts: https://tomverbeure.github.io/2019/11/21/Z-tape.html https://tomverbeure.github.io/2019/11/21/Z-tape.html