Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

3M tape with anisotropic z-axis electrical conductivity

3m.com

Post reply on HN
Print view View original

81–90 of 146 posts

Re: 3M tape with anisotropic z-axis electrical conductivity

#81

Post by tablespoon »

derefr wrote: post #61
djrogers wrote: post #57

Earlier quoted context omitted.

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.

> processing power; networking Could the device not simply get the host to do these things for it, by e.g. rootkit-ing the server’s BMC? A “hardware virus”, per se.

>> 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.

> Could the device not simply get the host to do these things for it, by e.g. rootkit-ing the server’s BMC? A “hardware virus”, per se.

IIRC, that's exactly what was alleged in the article. It was an implant that sat on the BMC ROM bus, fiddling with bits as the ROM was read during bootup. No need for any networking or processing ability beyond what was needed to that. This guy actually did a POC of that: https://trmm.net/Modchips/.

So totally plausable.

Re: 3M tape with anisotropic z-axis electrical conductivity

#82

Post by robomartin »

I went to look at this expecting it to also have excellent thermal conductivity (due to the low resistance z-axis conductivity through silver particles). To my surprise, it does not. The published range is 0.16-0.20 W/mK, which is pretty much what you get for most tape products.

We use specialized thermally conductive tapes in a range >= 1 W/mK. I am always looking for interesting developments in this domain.

Re: 3M tape with anisotropic z-axis electrical conductivity

#83

Post by Gravityloss »

markdown wrote: post #52
dxuh wrote: post #44

Earlier quoted context omitted.

That Netflix link is not available everywhere and also quite time-consuming to review. Obviously it is also a dramatic piece rather than a (semi-)scientific. I had a brief look at the PFAS wikipedia page ( https://en.wikipedia.org/wiki/Per-_and_polyfluoroalkyl_subst... ), which is what that Netflix movie seems to be about, but it's also quite wordy and the claims you make can not be found on there as-is. Maybe you wa…

https://www.popsci.com/story/environment/dark-waters-chemica... Basically, the US government allows companies to sell new chemicals they invent, completely unregulated. You could make a toxin today that kills everyone who touches it 10 years after they ingest it, and you would be free to market and sell this product. The chemical is presumed safe until evidence to the contrary comes to the knowledge of the govt. That…

There is now REACH in EU.

Re: 3M tape with anisotropic z-axis electrical conductivity

#84

Post by bialpio »

mlindner wrote: post #73
bialpio wrote: post #56

Earlier quoted context omitted.

Not sure if you'll consider this a more scientific source, but John Oliver also did a piece about PFAS: https://m.youtube.com/watch?v=9W74aeuqsiU . The list of issues that the wiki article claims are "high certainty" is also quite concerning to me: https://en.m.wikipedia.org/wiki/Per-_and_polyfluoroalkyl_sub... At the very least, seems that the production is being ramped down - quick skim of the article yielded this…

John Oliver is a comedian, so also not a very good source. It's written for entertainment rather than being informative.

I think it can be both entertaining and informative, but it definitely feels like they try too hard to be funny at times. Do you have an example where the information they stated in the show was factually incorrect about PFAS?

Re: 3M tape with anisotropic z-axis electrical conductivity

#85

Post by dale_glass »

01100011 wrote: post #12

A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. I guess they're dragged down by their environmental lawsuits these days. As a human, I'm appalled at their environmental track record but as an engineer, wow they really do so many things so well.

What's important is not only the amazing products, but also that they solve problems and that they can actually be bought by people who need solving those problems.

My anecdotal experience is that every time I run into some amazing 3M product, it costs $300/liter.

Nile Red recently posted this cool video of extinguishing a book with this fancy 3M liquid. Looked, yup, that's about the price.

If you wanted to experiment with fancy computer cooling, Fluorinert is also an arm and a leg in the quantities that'd be needed. It was apparently used in the Cray waterfall, but it seems after more than 30 years the stuff is still bloody expensive.

And so on.

Re: 3M tape with anisotropic z-axis electrical conductivity

#86

Post by onion2k »

dale_glass wrote: post #85
01100011 wrote: post #12

A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. I guess they're dragged down by their environmental lawsuits these days. As a human, I'm appalled at their environmental track record but as an engineer, wow they really do so many things so well.

What's important is not only the amazing products, but also that they solve problems and that they can actually be bought by people who need solving those problems. My anecdotal experience is that every time I run into some amazing 3M product, it costs $300/liter. Nile Red recently posted this cool video of extinguishing a book with this fancy 3M liquid. Looked, yup, that's about the price. If you wanted to experimen…

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.

Re: 3M tape with anisotropic z-axis electrical conductivity

#87

Post by dale_glass »

onion2k wrote: post #86
dale_glass wrote: post #85

Earlier quoted context omitted.

What's important is not only the amazing products, but also that they solve problems and that they can actually be bought by people who need solving those problems. My anecdotal experience is that every time I run into some amazing 3M product, it costs $300/liter. Nile Red recently posted this cool video of extinguishing a book with this fancy 3M liquid. Looked, yup, that's about the price. If you wanted to experimen…

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 getting at -- it's not enough to make cool stuff. The cool stuff also has to reach the people interested in using it.

Re: 3M tape with anisotropic z-axis electrical conductivity

#88

Post by aaaaaaaaata »

Rebelgecko wrote: post #70
01100011 wrote: post #12

A while back I invested in 3M because it's a company that makes so many amazing and industry leading products and I thought they'd do well. A couple years later and the stock is just lagging. I guess they're dragged down by their environmental lawsuits these days. As a human, I'm appalled at their environmental track record but as an engineer, wow they really do so many things so well.

If you didn't already know, 3M shareholders can sign up for an annual holiday box. It costs money to order, but it's still much cheaper than buying the individual components (although if you don't need command hooks or post-it notes it might not be worth it for you) Full disclosure: I am the proud owner of one share of MMM.

Proud, but only one?

What's the calculus there, and why proud — if you don't mind me asking?

Re: 3M tape with anisotropic z-axis electrical conductivity

#89

Post by peter_retief »

mardifoufs wrote: post #45
dan000892 wrote: post #17

This stuff is rad. I took a class on hardware implants with Joe Fitz a couple years back—on the heels of that wholly unsubstantiated Bloomberg article about China embedding rice grain-sized hardware implants into Supermicro motherboards that magically found their way only to select F100s and gov’t agencies—where we made a PCB to interface an ATtiny85 to an unpopulated UART header on some IoT device but instead of sol…

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…

Had me fooled, I got quite excited reading it, ashamed to admit.

Re: 3M tape with anisotropic z-axis electrical conductivity

#90

Post by aaaaaaaaata »

calvinmorrison wrote: post #59
systemvoltage wrote: post #23

Earlier quoted context omitted.

3M is an awesome company. I've worked with them to produce custom adhesives for us ($MM orders). Their products have exceptional quality, reliability and performance. What you see in a datasheet is what you're going to get (or better). 3M's consumer products (Scotch, etc.) are also excellent. Anytime you use 3M products, you don't need to worry. I like that consistency and it brings peace to the mind. I'll pay more f…

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......
Post reply on HN