Sciencemadness Discussion Board - Anti bike theft agent

Anti bike theft agent

Refinery - 29-5-2020 at 05:51

https://www.youtube.com/watch?v=ixPFDFp8Cfo

I was wondering if an U lock could be fitted with a metal tube that is hermetically sealed and filled with gas that is highly irritant but possibly not toxic so that if the lock is being cutted with bolt cutters or angle grinder, the ampoule would burst and force the thief to retract. The nature of the irritant could be anything from common pepper spray agents to a more effective solution, preferably a system that is pressurized so the contents will release at once when cut for full effect. A dye agent could also be included to cause semi-permanent marking for the perpetrator to allow for later identification. A clear marking or branding of the device would act itself as a deterrent.

Another factor regarding to the design of the lock presented in the video above, the bulk can be made out of material that causes intense smoke when cut with angle grinder. This concept is used in safes against torches.

clearly_not_atara - 29-5-2020 at 07:01

The problem with this idea is that there are legitimate situations in which it would be appropriate to cut a bike lock. As such toxic or noxious materials are not a good plan.

With that said, I think that the most practical choice is superglue. It should destroy an angle grinder on contact with minimal risk to human life. A similar choice would be gallium.

Deathunter88 - 29-5-2020 at 07:29

Where did you get that gallium or superglue would stop an angle grinder at all? Seems unlikely to me.

zwt2 - 29-5-2020 at 09:09

Pottery-grade manganese dioxide. It'll hamper cutting and leave stains like a dye pack.
Manganese can be toxic, but if you're cutting steel, you'll be exposed to several transition metals in dust form anyway.

mackolol - 29-5-2020 at 12:57

The best option, but rather theoretical is chloroacetone readily made from three reagents in simple synthesis in situ, but due to big toxicity and being not legal at all not to be use like that. Speaking about dye agent just paint it, but it would be only visible on hands.

B(a)P - 29-5-2020 at 13:00

Something similar to what the banks use would work well. Not chemistry related, but there are some good anti theft GPS based products on the market for bikes.

karlos³ - 29-5-2020 at 14:41

I guess you would have to pay in the end when the thief sues you, that is nowadays nothing unheard of in many countries.
Of course I could imagine it being filled with a bromoketone very well... but thanks to the monopol of violent force, under which an attack with a chemical agent surely fells, you would definitely be sued, especially in case innocent bystanders(i.e. the thieves friends) are affected, your punishment would surely turn out harder than anyones else involved.
I would even guess that the bike thief won't be punished, as any thoroughly ideologised judge would deem him the victim in such a case.

If you can pull that off without getting caught, why not though.
Then I would recommend bromoacetophenone, easily made, not at all wiped away, and it doesn't need to be pressurised... it is enough if the thief get it on his hands(its a weak blister agent though, add that to being possibly sued), but its not a gas.
He'll wipe them somewhere on himself(not possible without solvents), and he will feel the burn shortly afterwards.
If he even makes it on the bike, he will get maybe five meters away, and when you get back to your bike, you should probably call an ambulance because of the crying and whimpering thief(and then get the hell away before they get there).

It sounds pretty cruel though.
I wouldn't do this myself.

Chemetix - 29-5-2020 at 16:14

Lol, a vial of TiCl4 would be fun to try, reasonably harmless. But there are situations where that could be inappropriate, like a busy street with car traffic getting covered in thick white smoke.

G-Coupled - 29-5-2020 at 17:15

Fill your tyres with Mercury Fulminate when you lock your bike up.

[Edited on 30-5-2020 by G-Coupled]

XeonTheMGPony - 29-5-2020 at 17:45

Theifs deserve what ever they get, I'd be happy with Tabum!

50K of irreplaceable equipment stolen and my bike! they need to suffer greatly!

Chemetix - 29-5-2020 at 18:44

Since we've descended into comically exotic ways to murder thieves, there's cacodyl, a spontaneously flammable liquid in air. If the burns don't kill them, the cloud of arsenic will finish the job. Arsine or phosphine could be substituted here, but you'll probably kill yourself trying to make this anti theft device.

SWIM - 29-5-2020 at 19:14

You just need a depleted uranium hasp for that lock.

Anybody tries to use a grinder on that it's going to look like the fourth of July (Cinco de Mayo? Guy Fawkes day?...lots of fireworks is the idea.)

And if the sparks don't give the thief away the the uranium contamination should make for a short career anyway.

Pretty toxic, even as a chemical agent.

On a more serious note, a thicker hasp might be engineered with large internal differences in hardness so that any saw, drill, or perhaps even grinder disc, encounters heavy stresses that will break it.

This was done for some safes back in the early 20th century. I think they cast some softer metal with a framework of something much harder inside. It worked well against drills and saws- at least pre-WWII drills and saws- but I'm not sure it would defeat a grinder.

How about a thick steel tube for a hasp with notches like a flute cut in it so it whistles out a distress call when you put a grinder to it and it warms up?

The Vocal Memnon Bike lock.
Now available at S-Mart.

Shop smart, shop S-Mart.

@XEON below: Yeah, I forgot about that move. Some guys were doing that in Palo Alto for a while too.

They had a flat-bed truck and they'd take racks with a dozen or more bikes chained to them.

[Edited on 30-5-2020 by SWIM]

XeonTheMGPony - 29-5-2020 at 19:24

if the lock is hard they just grind off the bolts on the bike holder and take the whole thing in my parts

mackolol - 30-5-2020 at 11:00

Quote: Originally posted by Chemetix

Lol, a vial of TiCl4 would be fun to try, reasonably harmless. But there are situations where that could be inappropriate, like a busy street with car traffic getting covered in thick white smoke.

Reasonably harmless!? Isn't it maybe burning your skin and lungs as well as eyes and covering them in oxide?

karlos³ - 30-5-2020 at 12:08

Quote: Originally posted by mackolol

Quote: Originally posted by Chemetix

Lol, a vial of TiCl4 would be fun to try, reasonably harmless. But there are situations where that could be inappropriate, like a busy street with car traffic getting covered in thick white smoke.

Reasonably harmless!? Isn't it maybe burning your skin and lungs as well as eyes and covering them in oxide?

Well yes, it actually is.
Don't go full chemophobia with this, you wouldn't call muriatic acid out for burning your lungs, skin, eyes, either, no?
Its not bad because the fumes are obnoxious and repulsive and anybody will retreat from the area in such a case.

I'll give you an example: during my back then still mandatory basic training in the military, a few months less than a year, most of us got exposed to the stuff, in quite sizeable quantities even.
Not only once as well!
They haven't even told us about the stuff and its dangers, I guess it just wasn't that seriously harmless in their judgement(connected with eventual legal problems though if someone gets affected badly).
Only found that out a few years ago on accident what this "smoke" consists of.
I've always assumed it was some other fuming metal chloride, or PCl3 instead.

The reason to get exposed to this stuff was by the way its use in the so-called "smoke/fog throwers", which are used to generate thick and dense fumes and clouds to hide vehicles or such behind.
Those things are as far as I know loaded with only TiCl4, and the generates fumes are really biting, smelly, suffocating and generally unpleasant.
You are told to avoid the clouds, but well, you will do that anyway when you get to close and smell and breathe that accidentally in.
And guess what? Nobody died, actually not even one got hurt.

Its just not as bad as it sounds, and I mean, isn't it like this for every chemical?
When you read all the descriptions of its possible dangers, what it can do in the worst case, etc, etc....
I know so many who sound really harmful just from their warning labels, for example triethylamine sounds bad, causing chemical burns in your lungs, together with coughing bloody sputum out, etc... sounded quite scary and a friend who read that was quite shocked.
Everyone who worked with triethylamine knows it is a pretty tame chemical which isn't problematic to handle at all.
Luckily I read that only after I worked the first times with it, I only remember that because of the visibly horrified friend, who looked like his worst fear in that moment was me opening the bottle with it...

I simply wouldn't go after the description only, yes it is helpful and yes it should definitely be read, but you have to keep in mind they have to list completely every possible risk, without paying attention to the likelyhood of these risks.
Its for legal purposes, so it is actually more like some sort of scary sounding bureaucracy.

*Disclaimer: I can't actually say if it was really TiCl4 in those smoke thrower things, nobody told us.
But TiCl4 is the most widely used agent for this purpose here, so I am like 80-90% sure that I am correct with my guess.

brubei - 30-5-2020 at 22:35

cover the bike with COVID or AIDS

Herr Haber - 31-5-2020 at 11:28

@karlos: those things used to be hexachloroethane and zinc most of the time.
Google "HC Smoke"

Zinc AND Hcl to breathe for the infantry when the tanks pops them.
Though effective they were / are being changed for that reason.

Clearly not atara's suggestions are good ! A friend working historical buildings as a stone mason told me what happens when you use an angle grinder on lead. I can imagine your solution being as effective at least.

lavenatti - 9-6-2020 at 01:33

If you fill your sealed tube with butyl mercaptan you'd certainly end up with a youtube worthy video when a thief cut through it.

Tsjerk - 9-6-2020 at 03:23

Quote: Originally posted by lavenatti

If you fill your sealed tube with butyl mercaptan you'd certainly end up with a youtube worthy video when a thief cut through it.

That stuff smells so bad I'm sure you will stink your place up and there will be a smell around the bike for at least the first couple of weeks... Which will probably help against theft, but there is little to steal when the fire squad takes the bike first...

yobbo II - 9-6-2020 at 17:09

Electric shock device?

Yob

Sulaiman - 9-6-2020 at 19:09

fill the tube with compressed air, CO2 etc. and some talcum powder,
put a notice like:
"You may have been poisoned, please telephone xxxxxxxxx within 90 minutes to return my bicycle and purchase the antidote"

mackolol - 10-6-2020 at 12:02

Quote: Originally posted by karlos³

Don't go full chemophobia with this, you wouldn't call muriatic acid out for burning your lungs, skin, eyes, either, no?
Its not bad because the fumes are obnoxious and repulsive and anybody will retreat from the area in such a case.

Its just not as bad as it sounds, and I mean, isn't it like this for every chemical?
When you read all the descriptions of its possible dangers, what it can do in the worst case, etc, etc....
I know so many who sound really harmful just from their warning labels, for example triethylamine sounds bad, causing chemical burns in your lungs, together with coughing bloody sputum out, etc... sounded quite scary and a friend who read that was quite shocked.
Everyone who worked with triethylamine knows it is a pretty tame chemical which isn't problematic to handle at all.

I simply wouldn't go after the description only, yes it is helpful and yes it should definitely be read, but you have to keep in mind they have to list completely every possible risk, without paying attention to the likelyhood of these risks.
Its for legal purposes, so it is actually more like some sort of scary sounding bureaucracy.

Okay... maybe I overreacted it, but I just got pissed when I have read that it is harmless. In considered situation, even though it isn't even likely, one wouldn't know that he is exposed to anything dangerous. If he breathed lungful of it, it would be a problem.
Thank you for sharing your experience about such chemical. When I was making smoke grenades from hexachloroethane and Al, I avoided the fumes as I didn't want to be exposed to something I knew about.
It is also something new for me that TEA can induce blood coughing, even though if I thought about it, I would probably invent that excessive inhalation would cause such problems.

mackolol - 10-6-2020 at 12:06

I think that good option for bike theft agent would be something very stinky. Maybe thioacetone, but due to polymerisation and excessively spreading smell it would be hard to spot the thief.
I would probs go for cadaverine, putrescine or maybe some very impure amphetamine (the thief would have problems as it is illegal and well known for police smell, at least in Poland which has biggest amphetamine production in the Europe).
Some chemical that stinks very much and can help to spot the thief but is harmless.

Refinery - 11-6-2020 at 10:45

tert-Butyl Isocyanide it is, then.

If there is something that causes emergency evacuation of public places due to incapacitating odor, this thing comes handy.

It doesn't matter if the thief gets away, they will kick them out of every town.

I don't know what amphetamine smells like? Is it easily detectable, strong odor? Does pure/purified and dried amphetamine smell as well?

[Edited on 11-6-2020 by Refinery]

andy1988 - 12-6-2020 at 22:36

Quote: Originally posted by Herr Haber

@karlos: those things used to be hexachloroethane and zinc most of the time.
Google "HC Smoke"

Zinc AND Hcl to breathe for the infantry when the tanks pops them.
Though effective they were / are being changed for that reason.

Recent article on non-toxic, or lower toxicity smoke alternative, the coloured smokes look dull, easter coloured:

Quote:

The reaction between the basic component of the conventional formulation (potassium chlorate) and the organic substances that provide the colors gives rise to polychlorinated compounds that are carcinogenic.

Furthermore, mixtures based on hexachloroethane are often used to generate white smoke—and their combustion leads to the formation of toxic by-products such as hexachlorobenzene, hexachlorobutadiene, chlorinated dibenzofurans and dibenzodioxins. In the new formulation developed by Klapötke and his colleagues, potassium chlorate is replaced by the non-toxic nitrogen-rich salt guanidinium-5,5'-azotetrazolate, which is combined with several organic dyes as coloring agents.

Abstract:

Quote:

In this study, a progressive halogen‐free multi‐colored smoke system to obtain white, red, violet, yellow, green and blue smoke color impression is presented. In detail, the nitrogen‐rich salt guanidinium 5,5’‐azotetrazolate (GZT), which is usually applied as gas generator or propellant ingredient, was combined with different smoke dyes (Solvent Red 1, Solvent Violet 47, Solvent Green 3, Solvent Yellow 33). These two‐component smoke mixtures offer a convenient and safe multi‐color approach without any need of hazardous material. The author’s determined common smoke characteristics with respect to burn time / burn rate, yield factor, transfer rate as well as energetic properties and compared them with classic chlorate‐based in‐use formulations. To the best of our knowledge, nothing comparable is known in the literature. Therefore, nitrogen‐rich compounds as only ingredient in smoke mixtures open a completely new research area in modern pyrotechnics.

In the paper's conclusion on “nitrogen-rich-only” smokes:

Quote:

However, also the toxicity of these combustion products should be further evaluated to satisfy health aspects.

[Edited on 13-6-2020 by andy1988]

mackolol - 13-6-2020 at 04:24

Quote: Originally posted by Refinery

tert-Butyl Isocyanide it is, then.

If there is something that causes emergency evacuation of public places due to incapacitating odor, this thing comes handy.

It doesn't matter if the thief gets away, they will kick them out of every town.

I don't know what amphetamine smells like? Is it easily detectable, strong odor? Does pure/purified and dried amphetamine smell as well?

[Edited on 11-6-2020 by Refinery]

It sometimes smells like dead mouse or just dead body. For some this odor is intolerable.

Do you know how to prepare alkyl isocyanides? Does it go like alkyl halide + alkali isocyanide?

[Edited on 13-6-2020 by mackolol]

Refinery - 13-6-2020 at 05:23

I see. I've heard that it smells "fishy". One of my friend hangs out with junkies so I suppose I should ask if "I could have a smell, just out of curiosity" someday.

http://orgsyn.org/demo.aspx?prep=CV6P0232

The synthesis appears quite trivial by quick look and does not require any troublesome reagents.

Other thing to consider, though, is that TBIC is widely referred as the mother of all reeks and when I read some articles about it, merely being around those higly reeking chemicals is enough to imbue that odor to yourself.

https://blogs.sciencemag.org/pipeline/archives/2010/05/07/th...

There was a written note that a scientist worked with isocyanides, left work and showered and changed his own clothes at the workplace and at later night went to theater and got kicked out because "bystanders couldn't stand the reek". This made me think that synthesizing isocyanides is absolutely out of question at your home or anywhere near where you want to retain any resale value on a real estate market. A reasonable way would be to make it in glovebox fumehood in a temporary location with high chimney, seal the product in metal or glass ampules and then decontaminate everything with HCL, methanol and ozone.

Spraying a good amount of TBIC on a bike thief would certainly make his life miserable for a while.

[Edited on 13-6-2020 by Refinery]

mackolol - 13-6-2020 at 06:57

Quote: Originally posted by Refinery

I see. I've heard that it smells "fishy". One of my friend hangs out with junkies so I suppose I should ask if "I could have a smell, just out of curiosity" someday.

As I read the article n butyl isocyanide is the most powerful one. And due to wikipedia it is very dangerous causing similar damage as CO. I don't imagine working with it at all, but what interests me is how stinky is it in comparison with thioacetone.

Chemetix - 13-6-2020 at 20:05

Ahh the old Hoffman Carbylamine test. Stinky for sure.

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

you only need tiny amount, despite the toxicity no one will end up exposed to it long enough to be dangerous. My concern is that 1950's bad smell pranks would these days be considered a potential chemical weapon.

Fantasma4500 - 13-6-2020 at 21:08

make it thick steel and load it up with a heat sensitive explosive. cheers. good luck with having this thing legally hit the market though, as a bonus you should be able to hear when someone tries to take your bike unless maybe its a van of burglarians just picking the bike off the ground and driving back south with it

iodoacetone would also be interesting, odorless teargas, its too easy to make.

BaFuxa - 2-7-2020 at 08:40

[Edited on 2-7-2020 by BaFuxa]

artemov - 4-2-2021 at 23:26

Sorry to revive this, I have a genuine issue here

I installed a combi lock (see pic) for my mailbox located a certain distance from my place.
It seems that someone has been playing with the lock frequently, probably trying different combi to unlock it.
So I am thinking of maybe putting something on the lock to deter the fellow.

I have in mind silver nitrate, but I dun have it now and it's a bit too expensive to buy.
Any other suggestion?

I dun want to hurt or poison the guy, it could just be a naughty child!
It should also be relatively stable on the lock, though I can reapply it once every few days.
It should not destroy/damage the lock!
I can wear a glove to unlock when I need to retrieve my letters, no problem with that.

Cheers!

Fyndium - 5-2-2021 at 02:45

There was a thread about these very strong coloring agents. Might apply some to the wheels, and when someone touches it, it gets to his fingers and everywhere. Shouldn't be toxic as it's used for food.

Fery - 5-2-2021 at 23:33

1 drop of valeric acid in contact with thief skin e.g. (palms) and the thief will stink of vomit for few days, it cannot be washed out of skin. Plus 1 microcrystal of denatonium benzoate (Bitrex) at a surface which the thief must grab so the thief won't be able to eat with his bare hands for couple of days. Coloring agent? Crystal violet (Gentian violet) colors like a hell - it is used in medicine (oral candidiasis) or Brilliant green (eczema, local mycotic infections), Fuchsine = Solutio Castellani (pityriasis).

artemov - 6-2-2021 at 01:18

Quote: Originally posted by Fyndium

There was a thread about these very strong coloring agents. Might apply some to the wheels, and when someone touches it, it gets to his fingers and everywhere. Shouldn't be toxic as it's used for food.

Thanks Fyndium!

Quote: Originally posted by Fery

1 drop of valeric acid in contact with thief skin e.g. (palms) and the thief will stink of vomit for few days, it cannot be washed out of skin. Plus 1 microcrystal of denatonium benzoate (Bitrex) at a surface which the thief must grab so the thief won't be able to eat with his bare hands for couple of days. Coloring agent? Crystal violet (Gentian violet) colors like a hell - it is used in medicine (oral candidiasis) or Brilliant green (eczema, local mycotic infections), Fuchsine = Solutio Castellani (pityriasis).

But if I coat my lock with valeric acid, wouldn't it stink even before the thief lays his hands on it?

Bitrex sounds very very interesting

Fery - 6-2-2021 at 06:27

yeah, Bitrex = very delayed and long lasting punishment of the thief
10 g for less than 10 US$ which is enough for the whole life, just be careful with handling it

from UA
https://www.ebay.com/itm/10-Grams-Denatonium-Benzoate-Most-B...

from CN
https://www.ebay.com/itm/10-grams-Denatonium-Benzoate-Most-B...

artemov - 6-2-2021 at 06:30

Quote: Originally posted by Fery

yeah, Bitrex = very delayed and long lasting punishment of the thief
10 g for less than 10 US$ which is enough for the whole life, just be careful with handling it

from UA
https://www.ebay.com/itm/10-Grams-Denatonium-Benzoate-Most-B...

from CN
https://www.ebay.com/itm/10-grams-Denatonium-Benzoate-Most-B...

Yes I saw both of these. Thanks!
I'm just a bit worried for myself

I once had bitter mouth for a couple of weeks from eating pine nuts!

Fyndium - 7-2-2021 at 09:11

File a patent for U lock that has core made of pressurized tube which contains a solution of denatonium benzoate, valeric acid or a substance of low toxicity but high and persisting odor and a persistent coloring agent.

Cut it, and you make an aerosol cloud of immensely disgusting smelling stuff that makes you unable to enter any space where people habit and taints you whole in bright color and you can taste it a week after. Harmless to user as it's hermetically sealed in a steel tube.

Smearing any onto a lock is mainly harmful to the user.

Fantasma4500 - 21-5-2021 at 04:45

it probably wouldnt be legal, but im sure an angle grinder hammering away at a tube filled with even relatively safe flashpowder would make for quite the shocker, and possibly a bit of injury

maybe filling iodoacetone in there could work, or bromo or chloroacetone, not sure how much that corrodes but its plenty nasty, you would have to ram it shut with some type of plug, heating it would be a bad idea, as in welding it shut or soldering

Fyndium - 21-5-2021 at 08:41

Filling a metal tube with flashpowder does not differ at all from a concept of classic energetic pipe device, with added risk that the user will set it off due to any cause of static electricity. If that was the case, casting the tube full with ETN would be more effective. Someone would suggest also to use metal that is alloyed with something that releases extremely toxic metal oxides (like osmium tetroxide, etc) upon grinding it, but this goes well within the same category of "bike locks restricted in democratic countries".

Best idea so far has been this:

It's metal foam adulterated with ceramic granules. The dimensions could prevent bolt cutters, and the ceramic granules made from same or even harder material than angle grinder disc (afaik alumina, zirconia, etc), which will render it ineffective against it. The base material could be aluminum, steel or other metal alloy. Also the shackle frame would be made out of foam metal. After that, only diamond or possibly carbide cutters, torch and large enough mechanical cutters or benders could be effective.

I tried cutting tungsten electrode for TIG ages ago when I made tests with AP bullet inserts. I literally spent an entire disc cutting one 2.5mm electrode in half. Sintered tungsten (carbide) locks could hence possibly be also an option, if the price (and weight) were not an issue.

But it's not what can be broken in theory. It's what junkies and other lower forms of life can break on the street in few minutes with handheld tools.

[Edited on 21-5-2021 by Fyndium]

Vomaturge - 21-5-2021 at 11:05

As far as something you could pour on the lock to bother thieves, how about the graphite/ammonium chloride/manganese oxides mix from a dead zinc carbon battery, add a splash of water . Only problem is you might want a new pair of gloves every time you touch it. Yes MnO2 can be toxic by inhalation but this mix is paste-like and leaves black smears on everything. Washing it off of porcelain or plastic is quite the chore. Skin takes days of regular washing.

clearly_not_atara - 21-5-2021 at 11:45

Quote: Originally posted by artemov

Sorry to revive this, I have a genuine issue here

I installed a combi lock (see pic) for my mailbox located a certain distance from my place.

What you need is a hidden camera, not a chemical.

Fyndium - 24-5-2021 at 04:41

Quote: Originally posted by Vomaturge

Only problem is you might want a new pair of gloves every time you touch it.

I might be looking for a long-term solution that is non-hazardous to handle on a daily basis, and could also protect more expensive bikes without destroying them while doing so.

Vomaturge - 24-5-2021 at 10:55

What Clearly Not Atara said. Any “deterrent” chemical you put on the lock will be a daily nuisance whatever it’s mechanism of action.

Jenks - 24-5-2021 at 12:55

Quote: Originally posted by artemov

I have in mind silver nitrate, but I dun have it now and it's a bit too expensive to buy.
Any other suggestion?

Silver nitrate has always seemed overpriced when all it takes is to dissolve silver metal in nitric acid and evaporate the water. I like to take some of the solution out, basify it to get the silver oxide, and then add that back to the original solution. If it is in excess, it will use up any remaining nitric acid before evaporating the water.

A friend of mine one related that someone at work was breaking into his office, and he confirmed who it was by leaving droplets of silver nitrate on the doorknob and seeing who had brown stains or filed palms the next day.

I was also recently informed that traces of picric acid leave lasting yellow stains on skin.

If a lock were made of ferrocerium, it would at least be highly visible, and could possibly ignite, if it were to be cut with a grinder.

Fyndium - 28-5-2021 at 21:33

Many chemicals are ridiculously overpriced considering how simple their preparation is. Paying the price is warranted if it is needed at once, very small quantities or there are no facilities or precursors available for any reason. Some synthesis are also very easy in concept, but in practice need special equipment or are very arduous otherwise.

Silver nitrate staining is fancy idea. I noted, when I tested the benzaldehyde synthesis that the mother liquor of the reaction also leaves lasting yellow stains on skin. I would presume that higher-than-ghetto - level rogues would use gloves, primarily to inhibit fingerprint and DNA contamination, secondly to protect hands from damage if doing a break-in.

IrishJeremy - 29-5-2021 at 15:39

Just run a current through the bike, a la an electric fence. I'm sure that the circuitry and battery could be made small enough to conceal in a mounted water bottle, or even the frame. If not, cover the bike in Covid AND canceraids.

[Edited on 29-5-2021 by IrishJeremy]

Fantasma4500 - 5-6-2021 at 00:50

Quote: Originally posted by Fyndium

I tried cutting tungsten electrode for TIG ages ago when I made tests with AP bullet inserts. I literally spent an entire disc cutting one 2.5mm electrode in half. Sintered tungsten (carbide) locks could hence possibly be also an option, if the price (and weight) were not an issue.

[Edited on 21-5-2021 by Fyndium]

really? just drop it on the ground and it will snap right in half lol. funny how that works. titanium is also a total piece of shit to cut with angle grinder, i found an titanium golf club and decided to chop it into pieces, one of the parts was 3mm titanium and i think just cutting what 80mm of that was like one whole angle grinder cutting disc

maybe fill the tube with bromide/bromate mix, forms bromine gas, it does in solution so i think it should also work when just heated up, otherwise a plastic tube with water, or solution of either bromide/bromate, in same fashion as a glowstick could be put inside the device

ammonium perchlorate can also be really nasty, i had it forming some diabolic chlorine compound when i burned it off with nano copper powder made from CuCl2 + Al, it burns quite slowly, sort of glows rather.

Oxy - 5-6-2021 at 03:43

Quote: Originally posted by Fyndium

File a patent for U lock that has core made of pressurized tube which contains a solution of denatonium benzoate, valeric acid or a substance of low toxicity but high and persisting odor and a persistent coloring agent.

Personally I would use a DCM solution of alpha-bromoacetophenone or propiophenone derivative. DCM will evaporate quicky but those nasty chemicals will stay for a long time and will literally squeeze tears from the victim. It will be hard to clean it as they are hydrophobic as f**k.
The punishment should be memorized, this one will stay in thief's memory for a really long time

edit: I see karlos already proposed that

[Edited on 5-6-2021 by Oxy]

Fyndium - 5-6-2021 at 13:20

Quote: Originally posted by Antiswat

really? just drop it on the ground and it will snap right in half lol. funny how that works. titanium is also a total piece of shit to cut with angle grinder, i found an titanium golf club

I cut up 1mm thick titanium sheet for electrodes with no issues. I suspect yours was not actually titanium, or it was some special alloy.

Also, tungsten alloys can be really, really tough, over 3 times higher tensile strength than steel. Pure tungsten is brittle. I'm under impression that tungsten carbide U-locks could actually be the thing for an ultimate bike lock, but few people were willing to pay 500-1000$ for a lock, even if their bike were $4000(reference: WC powder costs 100$/kg in large quantities). Such a lock would be trivial to machine with EDM. Now, I wonder how no YouTuber has not yet made such a beast.