What's Z-axis on this tape? is it thickness?
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3M tape with anisotropic z-axis electrical conductivity
121–130 of 146 posts
Re: 3M tape with anisotropic z-axis electrical conductivity
#122For anyone looking for the interesting numbers: Insulation resistance: 3.4 x 1014 ohms/square Contact resistance: Direct link to datasheet: https://multimedia.3m.com/mws/media/66235O/3m-electrically-c...
To clarify, those figure are after bonding right? I understand that means it must be heated and compressed between conductors to reach those values.
Re: 3M tape with anisotropic z-axis electrical conductivity
#123Earlier quoted context omitted.
3M, Johnson Johnson, Church Dwight, and a bunch of really householdy name companies are all smack in the middle of NJ. It's a sweet spot if you want to hop a few big corporations in your lifetime and work your way up the chain.
Just hold your breath while you're doing so......
Yeah, plus in last week's thread, we learned that basically all of these CPG and domestic manufacturers (including some of these blue chip companies were the ones polluting these superfund sites!
Re: 3M tape with anisotropic z-axis electrical conductivity
#124If y'all have never been on McMaster-Carr, you are in for a treat: https://www.mcmaster.com
All kinds of stuff like this can be explored with a pretty decent UI.
Re: 3M tape with anisotropic z-axis electrical conductivity
#125Earlier quoted context omitted.
It was also quite a plausible hack. The faker, if indeed anything was faked, knew more than most. Enough to have done the thing for real.
It was completely implausible - the chip that was identified could not possibly carry enough processing ability to do anything useful as far as espionage goes, had no connectivity to networking, and there was never any evidence of communication from these devices to anything suspicious or unknown.
My understanding was that it sat between the BMC and its boot flash and (assuming it was real) was designed to bit-twiddle regions of the firmware as it flew past over SPI. So basically streaming strpos() (or maybe even counting bytes) and then sending some alternate sequence of data.
That would require some processing chops to handle whatever speed the SPI bus ran at, and a bit of space to store the replacement bytes. Firmly within the margin for plausibility with even basic off-the-shelf kit. Honestly depressing really.
Re: 3M tape with anisotropic z-axis electrical conductivity
#126Earlier quoted context omitted.
Yep! But it sadly cannot replace soldering for denser pinout layouts, unless a lot of pressure is applied. Someone tried though; https://tomverbeure.github.io/2019/11/21/Z-tape.html (A bit off topic but that Bloomberg story is still such a mystery to me. It went into quite a bit of details and claimed it had tons of sources, so even if it was a completely false story whoever fabricated it must have put insane amounts…
The Bloomberg story, my thinking is that it was probably true, but someone from national security forced them to clam up.
Yep. For the CIA or NSA or whomever quashing that story is a good short-term solution (protecting your spy IP - spy P?) and also medium-term (harming Bloomberg's reputation), but the longer term side-effects (harming media's reputation in general) probably ended up doing far greater harm to the US. Trust is so easy to destroy, and takes a very long time to build up again.
Re: 3M tape with anisotropic z-axis electrical conductivity
#127Earlier quoted context omitted.
> Fluorinert is a super niche product. I mean, that goes both ways. At that price it will always be a super niche product, and never graduate to "plain niche". Look at the enthusiast market, there's no lack of fancy water cooling gizmos out there. They're bought by a small segment, but there's still a market for fancy gizmos to provide the best cooling for overclocked high end hardware. And that's exactly what I'm ge…
I suspect some of these products have a funny price curve. If Fluorinert costs $300/litre today and you cut the price to $100/litre - that's still far too expensive to become a mainstream PC coolant. It's not like there's a proven market for mineral oil PC cooling. Could be, if you cut the price of Fluorinert by 2/3rds, you'd just be giving a discount to your existing customers, for whom price is no object anyway.
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Re: 3M tape with anisotropic z-axis electrical conductivity
#128Earlier quoted context omitted.
Agreed, they're the most comfortable ones I found without an exhalation valve. Conveniently they also fold flat. Only downside is that they go behind the head instead of using ear loops.
I can't stand ear loops anyway, they hurt my ears. It helps that my hair has grew out during the whole "don't get close to people" thing. Ponytail + around-head straps is a great combo for maximum snugness (you can loop the top one under and the bottom one over).
I think it just varies, but I'm with you. It might be because I also wear glasses, do you? I feel like the ear loops press my glasses harder into my ears, preventing longer term wear (they're great for a half hour, not so good for six hours straight).
I mostly use behind the head but foldable ones now, the ones to TC-84A-9315 spec (H95W) are pretty good for me but my nose is a bit too pointy to fit right at the nose. They seem to work really really well for people with slightly flatter features, the little nose metal form doesn't quite hold well enough.
Re: 3M tape with anisotropic z-axis electrical conductivity
#129Earlier quoted context omitted.
I suspect some of these products have a funny price curve. If Fluorinert costs $300/litre today and you cut the price to $100/litre - that's still far too expensive to become a mainstream PC coolant. It's not like there's a proven market for mineral oil PC cooling. Could be, if you cut the price of Fluorinert by 2/3rds, you'd just be giving a discount to your existing customers, for whom price is no object anyway.
Mineral oil is _very_ messy, which really doesn't help at all. And the one company that sold the tanks had to stop due to some patent nonsense.
According to https://en.wikipedia.org/wiki/Fluorinert#Toxicity Fluorinert has to be limited to closed systems because it has "high global warming potential", it can decompose into a highly toxic gas, and "care should be taken to avoid contact with eyes and skin" (I'll admit I'm not sure how all this squares with the 'inert' in the product's name)
To me this sounds more difficult to use than mineral oil, not easier.
Re: 3M tape with anisotropic z-axis electrical conductivity
#130Earlier quoted context omitted.
it seems after more than 30 years the stuff is still bloody expensive Fluorinert is a super niche product. The price reflects that. I imagine the cost to produce it has dropped dramatically in 3 decades. 3M just make more profit from it now. As products mature there's no reason to believe the production process and efficiency savings will always be passed on to the consumer.
> Fluorinert is a super niche product. I mean, that goes both ways. At that price it will always be a super niche product, and never graduate to "plain niche". Look at the enthusiast market, there's no lack of fancy water cooling gizmos out there. They're bought by a small segment, but there's still a market for fancy gizmos to provide the best cooling for overclocked high end hardware. And that's exactly what I'm ge…
Isn't Flourinert a PFC and thus really dangerous/impactful in terms of accelerating global warming? I think we do well to keep its use to niche applications.