3M Glass Cloth Tape 361 | Hacker News Reader

3M Glass Cloth Tape 361

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105 pointstosh119 comments

My favorite tape for attenuating bright or annoying LEDs is ruby litho tape (3M Lithographers Tape 616). It passes deep red light and dims bright green and blue LEDs to a faint red. It's perfect for green/amber status lights; the green "OK" is mostly blocked and the amber "Problem" shines through. Removes easily without leaving a mark.

https://www.3m.com/3M/en_US/p/d/b40068069/

https://www.amazon.com/3M-Lithographers-0-375-width-length/d...

Good to know. I wasn’t even aware such a tape existed when I covered some powerful blue leds that were interfering with my sleep. Sometimes I wonder if the correct leds are used for status leds. The blue LEDs Im talking about were lighting up a whole wall at night and from somewhat useful they turned to a nuisance of sorts.

Blue leds are an obviously incorrect choice; they are only used because are novel and trendy (well, I guess they used to be novel and trendy, anyway). Human color vision is the least sensitive to blue light – but human low-light vision is the most sensitive to it!

As someone who is red/green colour blind, I disagree that they are an incorrect choice.

Annoying at night yes. But wherever they are used I can finally make out the difference between an ok/nok status.

Ah, I’m red/green blind too but most blue leds in electronics don’t seem to have a status function beyond "on/off", they’re there just to look futuristic.

Yeah my phone charger has a super bright blue led in it. It's kept in a draw at night as the entire room lights up. I keep meaning to cut out the led.

my best guess for blue lights is that it's one of the ones with higher energy efficiency and red/yellow would indicate problems.

One of my HP switches have setting for that, you can choose a time interval when the lights should be dimmed or turned off.

Thankfully the era of "slap blue led so the hardware looks modern" is over (back then blue leds were new thing and pretty expensive), but some devices still go too bright.

Status LEDs should be only bright enough to be obvious, they should be frosted/opaque, and should only be Red, Orange, Yellow, or Green.

Retina searing water-clear blue and violet LEDS have no business being used for any status light anywhere. Even in bright light, the better choice would be bright green due to the eye's sensitivity being maximum in the green.

Fun fact: rubylith tape was one of the tapes used to "tape out" early chip designs.

Wait, what? I thought the term "tape out" came from the original process whereby the design would be exported to a data tape for transport to the fab.

What do you think they did in the early days, before such things as data tapes or anything that could read them even existed? It used to be all photo masks, and the masters for those photo masks were made with... tape. Usually rubylith. Always by hand.

> the original process

The "original process" of integrated circuit design was cutting rubylith - this was well into the 70s. The venerable MOS 6502 was done this way as was the Intel 8008.

The verb tapeout was used for litho prior to integrated circuits though, back into the 40s.

But you should realize that PCBs and integrated circuits predate generally available computers and digital data storage.

> exported to a data tape for transport to the fab.

There was an article in The Register years ago that promulgated this misattribution - it was generally never a reliable source, no exception here.

That's why IC layouts used to be called "floor plans". They were floor-sized drawings on which people laid out lines with tape. The floor plan was then photographed from above and color-separated into masks.

"Back into the 40s?" ICs aren't that old.

Printed circuit boards have long been laid out by hand, and sometimes still are, but they're not usually photo-reduced. They're laid out at full scale.

> "Back into the 40s?" ICs aren't that old.

I think the parent is saying that the verb 'tapeout' goes back to litho processes before litho's use in IC production, not that IC production went back to the 40s.

Can confirm. When I was a kid I was an offset printer. We used rubylith for that. Then I learned PC design. Rubylith again. Then I went to work for an IC design firm. No rubylith there; our product produced Gerber file tapes. But the old-timers still called it "taping out" because it used rubylith before the Gerber days.

Is that Amazon listing legit? Price seems to be significantly cheaper than anywhere else

Good question. I Last bought a 60 yard roll for $12.50; sold directly by Amazon. Looks like it's about $14 now. Here's the listing: https://www.amazon.com/gp/product/B00JX9D6I2/

The listing in the parent comment is for 5 yards.

My second favorite tape is Honda's spicy rodent deterrent tape. It's made in Japan with capsaicin. It's not cheap, but much cheaper than an wiring repair at an auto shop*. The lowest price I was able to find seemed be be a dealer in Colorado … until I created an account, went through the order and saw the ~$20 S&H. The best deal including shipping was from the same dealer on eBay — no S&H charge.

https://www.teraokatape.co.jp/english/products/no/no300/data...

Rats chewed through wiring in my car on two occasions. Both occasions were in cold weather and the chewed wires were above shelf-like spots in the engine compartment. One was a transmission solenoid wire and the other was the ignition wire in the main harness above the wheel well. In both cases I was able to self-repair by popping the pins out of the wiring connectors and soldering new leads (pig tails) to the pins. YouTube has several videos explaining the process.

civil aircraft engineers will carry this and 3M 425 aluminium ‘speed tape’ with them which covers most jobs.

This is for sealing the cargo hold wall panels to ensure they are completely covered in flam proof materials. Normally a visual inspection is carried out each week to look for any damage in the holds.

For reference. MEA A320 weekly check https://masco.com.lb/wp-content/plugins/documents/A320%20WEE...

Tangent but this caught my eye:

>Cleaning of vacuum waste lines with chemical cleaning agent and crushed ice

Is there like a special ice cleaning slurry they use? Or do they just dump a bucket of ice and some chemicals in the lavatory and flush?

Just some ice and chemical then flush.

Skychem or Honeybee 76 is the chemical

Some people use ice to clean RV tanks too. Flush a bunch of it then drive a while and let it bang around as it melts then drain it. Probably would work on a boat too.

Yeah. Used to do this in my years of traveling in a fifth-wheel. Works great.

Works well for garbage disposals. Also a good way to get rid of freezer ice that's bern through too many defrost cycles.

And in between checking maintenance log book and tire pressures:-

Replace the Espresso Machine Frother P/N: 227431250 as per DEV 338A Part III

At the Baku Formula 1 race this year, the Alpha Tauri team taped together the rear wing on Yuki Tsunoda's car when it began flapping around—perplexing some fans. (Dynamic adjustment of the wing didn't work after that, of course, and more importantly Tsunoda finished thirteenth outside of the points, making the effort moot.) In the discussions, it surfaced that ‘speed tape’ is what's used in F1, also with some educating photos like an airplane turbine being sealed with such tape.

13th is still respectable, and if the people in front had issues they would have gone up in the ranks - better to finish in less than ideal circumstances than not try at all.

Eh, five drivers retired from that race, including both Ferraris—so Tsunoda was in fact third last, ahead only of young Schumacher and Latifi. I mean, it was an okay try, but regrettably it went nowhere.

Young? I'm pretty sure he was racing when I was a child 30 years ago.

That's the not-young one. This year's Mick Schumacher is Michael's son. In fact, he's thirty years younger.

There's a driver at age 30 and has a son 30 years younger than him who also drives?

The father (Michael) is 53, and he has been paralyzed for almost 10 years after a skiing accident.

IIRC it's surprisingly common to see bits of speed tape on commercial airliners, used to temporarily seal things off until they can be repaired more permanently.

Tangent to this: there was an airline accident when the service crew used transparent tape instead of the reflective silver tape somewhere on the belly of the plane (or wings, I don't remember). Then when the pilot was doing preflight inspection at night with a torchlight, the spot with the transparent tape was not visible to him. This was an error on the ground crew side.

It would need some googling to find the details.

Aeroperú Flight 603: "Flying over water, at night, with no visual references, the pilots were unaware of their true altitude, and struggled to control and navigate the aircraft. The investigation determined that the air data computers were unable to show correct airspeed and altitude on cockpit displays because a maintenance worker had failed to remove tape covering the pitot-static system ports on the aircraft exterior"

https://en.m.wikipedia.org/wiki/Aeroper%C3%BA_Flight_603

How does 3M 425 compare to 3M 3340? 3340 is some foil tape I bought from Lowes in the HVAC section, with "cold weather" printed on it in red text.

In terms of thickness, I see 425 is 2.8 mils thick, vs 3340 which is 2.0 mils.

In terms of temp range, I see 425 goes down a bit colder (-65 F vs -40 F).

They seem really similar, like 425 is a somewhat improved version. But it's surprising that this comparison PDF, which shows a lot of 425 alternatives, doesn't show the basic stuff I got from Lowes (3340) https://multimedia.3m.com/mws/media/1390627O/3m-aluminum-foi...

The 425 seems to have higher steel adhesion and tensile strength. 3340 looks to be specifically geared towards HVAC.

Here’s a pdf to help select metal tapes:

https://multimedia.3m.com/mws/media/856073O/3m-metal-foil-ta...

And the data sheets for both tapes:

https://technicaldatasheets.3m.com/en_US?pif=000010?locale=e... https://technicaldatasheets.3m.com/en_US?pif=000116?locale=e...

And some more tape pdfs, honestly a lot of it is super interesting, I never put much thought just into how many different kinds of adhesives there are:

https://multimedia.3m.com/mws/media/1016166O/3m-masking-and-...

https://multimedia.3m.com/mws/media/1015901O/3m-industrial-a...

https://multimedia.3m.com/mws/media/1012104O/3m-converter-ma...

>Silicone adhesive provides good holding power and clean removal across a wide range of temperatures

Adhesives are amazing... I wish I understood them better.

agree. materials science in general is far more interesting than i would have guessed when i was a student.

But the design-fabricate-test cycle is much longer than a typical edit-compile-test cycle. What do you do in the mean time?

Run overlapping projects/experiments concurrently.

This resource covers every level from pop sci to pro https://www.stevenabbott.co.uk/practical-adhesion/

What a great link, thanks!

This video about the Lotus Elise was pretty interesting in its description of how Lotus used adhesives to save weight.

https://youtu.be/h0jXhOmL7Xg?t=334

Without getting into how I know this… there are a few McClaren vehicles with class-A (outside, pretty part) body panels that have no screws, welds, or attachments. They are glued on and not meant to come out, but a few block the only access to X or Y part. The technician comes in, takes a razor, cuts the panel out at the glue, does the work, cleans the old glue off and glues panel back on. It’s actually pretty amazing.

They truly are amazing. My first time choosing a specialty adhesive, following all the instructions for surface prep, and then testing the strength of that joint - I was blown away.

One I recently thought about is the adhesive on Oreo packaging in the US (maybe elsewhere as well). It seals well without becoming immediately “unsticky” after opening. Magic

Anyone have any examples of what they use this for? I don't have much that needs to be taped AND fireproof.

Had the same question. I always have a roll of that aluminum tape around and find uses for it in hot spots. This seems like it could be better in cases where there’s some flex. It’s probably got a lot higher tensile strength than most tapes, too.

If, say, you had a crystal oscillator or voltage reference that is temperature-compensated or oven-stabilized, but also vulnerable to short-term instability due to convection currents or other airflow-related issues, you might wrap it in this type of tape, or use the tape to secure an aluminized heat wrap material that doesn't adhere well enough on its own.

Or if you're out of https://www.grainger.com/product/3M-Duct-Tape-Nuclear-Grade-...? and need something in a pinch.

Obscure thing to see here, for sure.

The recommended applications seem like they make sense?

> * Permanent sealing of high temperature ducts or chambers

> * Applications requiring heat treatment followed by clean removal of the tape with little or no stain

> * Protect surfaces against abrasion

> * High temperature masking

> * Bundling, holding and wire harnessing

It is expensive enough that you only want to use it when necessary, but they [1] built this place [0] with it. The hot water drill they used to bore into the Antarctic ice cycled between +100 degrees C and -40 degrees C daily, which caused it to develop leaks. This tape is one of the few materials that can survive in those conditions and hold the thing together. Nothing else they tried could do it.

[0]: https://icecube.wisc.edu/ [1]: http://www.psl.wisc.edu/projects/large/icecube

These specialty tapes seem expensive but when you need them you need them and nothing else will help. And then the price does not matter that much.

Winterover '20-21 here (there are other WOs on HN). We call it "driller tape" because it's was used all the time when the strings were installed (i.e. during drilling). Generally useful stuff for sticking things outdoors, though you do need to be quick with it. We also have a lot of teflon coated cable on station because everything else goes rock solid within a few minutes in winter. I rewired a bunch of people's heated goggles with that stuff (with an adapter for an off-head battery) because the factory cabling would break.

However it's not made by 3M, the stuff we have at Pole now is Nitto P-212 [0][1]. It's possible we or other experiments used 3M in the past - given it's been a decade since we broke the ice - but the stuff on station definitely has that blue/white branding on the inside of the roll.

Just to give an idea of how oddly stringent we are down there, and how experimental a lot of this is - regular things break all the time even in relatively controlled environments. Simple solutions like that tape are preferred where possible. The year before I wintered, the IceCube summer crew had to replace over 100 PSU fans in the cluster with equivalent Noctuas because the OEM ones would fail weekly. We did the same with DOM power supplies - I think we use exclusively Meanwell now. Never had any issues with those in my deployment, so it made quite a big difference. It's a harsh continent :)

[0]: https://www.nitto.com/eu/en/products/e_parts/heat_resistant0...

[1]: https://www.cambridge.org/core/journals/annals-of-glaciology...

To be fair I never spent time on the Pole myself (though I did get to ship one piece of Irreplaceable Science Stuff* thataway...) (*Containing punch cards! Real genuine punch cards! ...as shims.), I just spent some time about a decade ago onsite in China with Jeff, where he talked quite a bit about driller's tape and how we didn't have any there in China. I tracked down the stuff myself based on his description, so I'm not surprised if I got the specific manufacturer wrong.

The 3M stuff certainly looks identical. That said, 361 is only rated down to -54 C and it gets colder than that over winter, maybe Nitto performed better in testing? Honestly I don't think many people could tell you the brand without looking it up, we all call it driller's tape. I used some to attach a solargraph (really, a failed attempt to make a lunargraph) on some railings for most of the winter and it was still there when the sun came up. Can't think of too many things we'd use it for outside though, mostly temporary things or labelling/fixing stuff to poles. The absolute performance probably doesn't matter too much relative to "does it work at -20 to -30 C reliably" (i.e. summer conditions).

What an amazing place to work. Does anyone blog about life there?

You can look at IceCube's website - https://icecube.wisc.edu/category/news/life-at-the-pole/

That's a condensed public-friendly version of the weekly reports we submit during the year. Frequently updated.

Probably the best complete blog is Raffi's, she's got more than one person inspired to apply for the job:

https://nechnif.net/

I think I read it one sitting and I put my application in a couple of months later, it's a really wonderful account.

There are also several people who vlogged their experiences (Joe Spins the Globe, Gone Venturing, etc)

Myself, I often use it as a back-up strip for submerged arc welding.

(Well, I would if I did any submerged arc welding...)

I recall running into glass cloth tape, and it having some savvy use in glassblowing… but I can’t remember what.

Yowza. 2.25" roll, 60 yards long is $280 on $bigsite. 33.75 sq ft. I guess $1.55/linear-foot of pretty wide (2.25") very awesome tape aint that bad but this is definitely a bit more than I was expecting. Sounds rad though, keeps planes flying, so I get it.

Comments also mention 425 aluminum "speed tape", which seems to be between half to third the price.

I need this tape. For my collection.

Here it is at Amazon

https://a.co/d/g6NchR8

Definitely one more tape to add to my bin of tapes: various widths of kapton, various vhb mounting tapes, anisotropic electrically conductive 9703, and ultra-slippery rulon tape... all of which I never use of course.

and the helicopter leading edge tape, I have a 50m roll I have used 3 iches of.

Bi-directional filament tape (aka "hexayurt tape") is a good one. Bonds quickly to most things, has absurdly great tensile strength as well.

I also have an "exotic tapes" bin. :)

Here's a list of other types of adhesive tape:

https://en.wikipedia.org/wiki/List_of_adhesive_tapes

For example, do you already have a toupee tape in your collection? :)

VHB has gotten me out of mounting jail free many many times.

This the kind of thing I wouldn't buy at amazon. It's small, expensive and mechanically simple. A good recipe for counterfeiting.

I've got a propane pizza oven which has some hot spots on the base.

Could I use this tape to cover up some of the holes in the bottom gas pipe to reduce the amount of heat which hits the base?

Are you referring to the burner? That's far hotter than this tape can withstand:

Withstands temperatures from -65°F/-54°C to 450°F/232°C and intermittent temperatures up to 550°F/288°C or higher, depending on the type and duration of the heat source

Any tape that can do it?

Basalt tape might be an option: it's commonly used for car exhaust insulation.

As hot as exhaust pipes get, I doubt it would compare to being directly next to an open flame.

A gas flame (ie. The blue ones when air is premixed) don't give off a lot of radiant heat, so anything below them ought to be okay.

Sounds like a job for kaowool.

I bet this tape would still work though given that his application doesn’t require high strength or residue-free removal.

The correct/ideal tapes will be called “refractory tapes.” They are essentially clay-like strips.

It's covering the gas outlets of the burner; the gas doesn't ignite till it's a little way beyond the burner, and most of the heat would rise (some would radiate down, and some radiant heat would reflect back off the plate/grill). So it _might_ not get too there, and this might work. Though I think a strip of aluminium wrapped around the spot would probably be easier.

No, but I bet a metal hose clamp would work.

Look for Thermo-Tec 13575 or similar part # at your local auto parts store. It will likely work better than glass cloth tape for that purpose.

Glass cloth 361 sounds like a good name for a cloth to wipe Go (the game) stones.

Sounds like a prog rock band to me.

How much does this stuff cost?

4 USD per yard: https://www.amazon.com/dp/B00LN84Q2G

Or $105 for 60yd

https://www.digikey.com/en/products/detail/3m/361-3-4-X60YD-...

Are aerospace engineers really working in 'yards'?

Flight itself is certainly done in feet and knots and such.

But I would hope that fasteners on aircraft are all metric these days.

absolutely.

if you need a single simple example nearly any cloth-composite is commonly sold in yard lengths.

There is no metric on the moon.

For all the grief 3M has put on humanity they still make some pretty neat stuff.

Sometimes I just bump around their site looking at all the neat stuff they offer and especially the oddball niche application stuff. They really have a glue or tape for just about any scenario!

The best places for that are websites like Grainger and Fastenal. They sell all the things you see all the time in commercial businesses, but never realized you could actually buy. (Of course, they tend to be surprisingly expensive.)

Also, check out U Line. They are more packaging / facilities focused.

I remember 3d printing a pokeball that I wanted to swing open automatically when a latch was opened. Struggled finding anything useful until I hopped on Grainger where, lo and behold, they had a little spring that was perfect for it.

The guy on the phone was really helpful too and held it for pickup.

Genuinely serious and ignorant question: What grief?

As a huge chemical conglomerate with a long history, they've been involved in their fair share of pollution incidents and other controversies.

https://www.bloomberg.com/graphics/2022-3m-pfas-toxic-foreve...

https://www.reuters.com/business/3m-agrees-pay-98-mln-resolv...

Management by post it notes comes to mind.

3M products are great because they always do what they say they're going to do. They usually even overperform by a large margin. They're one of my suppliers of choice for industrial applications or anything R&D where we don't quite know how good it has to be yet.

3M toxic chemical waste is also a core 3M product, and overperforms too. Some of their Superfund sites, particularly the C8/PFOA/fluorinated crud ones, are among the worst around. (I grew up on the other side of the city from their worst one! Yay!)

And, like any company in the fluorinated chemicals business, 3M has overperformed at ozone depletion and greenhouse forcing. I can give them a pass on that particular one, since society as a whole didn't care much about that stuff until recently. I can't, however, give them a pass for how nasty Scotchgard was/is and how much of it was sprayed on/near me as a child. If you remember Scotchgard, don't look up what it really was or you might regret your parents' life choices.

I recall once researching superfund distribution on some sort of thesis that the West Coast is Better, only to discover that Washington State is top ten for a superfund sites, and in large part because of all of the nasty ways we’ve come up with to preserve lumber over the years. Well, shit.

It’s no PFOAs but it’s a class of chemicals specifically selected for preventing decay so it’s up there. We really should know better by now.

People get mad at concrete re:co2, but compare its lifespan to wood, without preservatives.

How many houses, without preservatives in the wood, would rot and be rebuilt, compared to 100% concrete/rock housing?

And with each rebuild, comes all the wiring, plumbing, which is rarely recycled well, and recycling isn't environmentally cost free.

ICF seems a good idea to me.

Probably very few since interior wood is not pressure treated.

> How many houses, without preservatives in the wood, would rot and be rebuilt, compared to 100% concrete/rock housing?

This isn't a great comparison, as unreinforced concrete is not used for structures. If you're speaking about steel reinforced concrete, they usually have a lifespan in the 100 year range for something protected from the elements like structural walls (assuming the aggregate is well chosen to avoid sulphate attack). For comparison, much of the housing stock in my area is stick framed and is of a similar age - ~70 years.

You’re not wrong, but there are also any number of rules about building code that try to prevent water infiltration, which makes the wood last many times longer.

For instance, wood laid horizontally in water doesn’t wick water as far as wood standing vertically in water. If you look at deck and house designs you see a lot of horizontal pieces. Especially in new construction.

That said, letting water pool at the corner of your house can eat your foundation too. Water is bad. Get rid of it.

Preservatives aren't to prevent rot, but instead, to prevent insect, mould, fungus, etc from eating/rotting the wood.

Moisture can come from the air, and damaged/poor air separation. Insects are, well, they're insects.

And of course, there are mice, ground squirrels, and other critters which chew on wood relentlessly. If I didn't kill 100+ mice a year, and a few ground squirrels, I'd be up to my elbows in critters, not to mention, dead from the hantavirus, and my house burned down from wire damage.

German maker Laura Kampf is doing a video series on restoring a a 140 year old house. It turned into a much bigger project due to water damage that destroyed large parts of the wood frame and stone work. It’s interesting to watch if you’re into that sort of thing. She’s more of a maker type than a home renovation type so she comes at it from a different perspective.

https://www.youtube.com/playlist?list=PLLsyCFICnr819K6cWPGm1...

When I was a kid, finding water damage on This Old House projects would increase the budget by 50%. The owners always looked like they wanted to puke during the wrap up episode.

You probably don't want 100 or even 50 years old wiring and plumbing tho.

And it only "helps" if the future owner doesn't decide to destroy it and build something else anyway

This reminds me of the "designing a house to last 1000 years" article discussed on here earlier in the year, and the many factors that the author considered there.

https://constructionphysics.substack.com/p/how-to-design-a-h...

One can go down a pretty nasty toxic waste rabbit hole if you research all the attempts at chemical treatment for wood utility poles (for electrical grid and telecom, historically). Particularly a place like WA, OR, ID, BC having plenty of trees also has a mostly aerial electrical and telecom distribution last mile. And of course the companies that own and must maintain these poles have an interest in them lasting as long as possible...

My understanding right now is they've gone back to more traditional tar/creosote impregnated and coatings.

Don't forget rail ties!

I met someone whose ancestors lived in Missouri clearing the swamps. Those swamp trees made good railroad ties. And then creosote was introduced and the ties lasted ten times as long, so demand crashed over the next few years as the old ties were swapped out one last time.

As near as I can tell the economy never recovered. They grew cotton but that’s mostly overseas now too, and at any rate means arsenic accumulation.

Some people were trying to engineer a strain of rice that absorbs less arsenic. Apparently cotton and rice growing conditions overlap enough that this is a potential option.

Scotchguard is the biggest black eye I know of. I don’t know what’s in it now but it used to be cancer in a can.

Old formula Scotchguard had PFOS in it from the 1950’s until sometime in the last decades. People sprayed it on their furniture, indoors. We’re worried about off gassing from pans, and here was a can of the stuff in aerosol form.

Maybe ask instead of downvote?

You (and most Americans... maybe most humans), have PFOA's (forever chemicals) in your blood that came from 3M.

https://www.healthvermont.gov/sites/default/files/documents/...

https://theintercept.com/2018/07/31/3m-pfas-minnesota-pfoa-p...

There are times when they have been less recalcitrant than their competitors. Faint praise for sure but when you are doing PR bits for recapturing solvents for reuse instead of exhausting them or burning them, years before your peers are getting sued for not doing the same, you might not be angels but you’re also probably not the devil either.

One of those 3 Ms must stand for "malevolence".

My grow room needs absolute darkness for 12 hours to be optimal. Even 1 tiny LED light on a device eventually illuminates the entire room to my eye after some minutes. So I put a super thin bit on my drill and break the light.

Why don't you just illuminate the room 24x7 with green overhead lights? And by green, I mean the color itself. I've found that you can operate in the room and with the complete absence of both red and blue all photosynthesis should be halted.

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