# Undetectable knives - Legal to sell and carry? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 31, 2003, 4:49am UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379 "2003-03-31T04:49:02Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [March 31, 2003, 4:49am UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/1 "2003-03-31T04:49:02Z")
Now I appreciate a well made knife as much as the next knife geek, but isn’t this non-detectable “letter opener” obviously being sold as a knife that you can slip through metal detectors, or is “Ztyel” plastic (usually used in handles) the blade material of the future? [BC-LETTER Blackie Collins Assisted Opening Letter Opener](http://www.1sks.com/store/blackie-collins-letter-opener.html) > [@](#): > > Non-magnetic with assisted opening technology, the Blackie Collins Letter Opener is designed to be a unique conversation piece or last ditch self defense tool. > > Completely non-magnetic with Beryllium Copper springs as the only metal parts, the letter opener can be sharpened razor sharp and is made entirely of glass filled polymer. ---
**Author:** ![j\_kat\_251](https://avatars.discourse-cdn.com/v4/letter/j/71c47a/32.png) [@j\_kat\_251](https://boards.straightdope.com/u/j_kat_251)\ **Post date:** [March 31, 2003, 5:15am UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/2 "2003-03-31T05:15:56Z")
Sweet. I wonder how long entirely plastic/polymer guns will take to invent. Awesome. Smuggle dangerous weapons wherever you please. ---
**Author:** ![Incubus](https://avatars.discourse-cdn.com/v4/letter/i/c68b51/32.png) [@Incubus](https://boards.straightdope.com/u/Incubus)\ **Post date:** [March 31, 2003, 5:31am UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/3 "2003-03-31T05:31:45Z")
> [@](#): > > \*Originally posted by j\_kat\_251 \* > \*\*Sweet. I wonder how long entirely plastic/polymer guns will take to invent. Awesome. Smuggle dangerous weapons wherever you please. \*\* Ever heard of the Glock-9 pistol? ---
**Author:** ![j\_kat\_251](https://avatars.discourse-cdn.com/v4/letter/j/71c47a/32.png) [@j\_kat\_251](https://boards.straightdope.com/u/j_kat_251)\ **Post date:** [March 31, 2003, 5:38am UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/4 "2003-03-31T05:38:47Z")
I have now! My country isn’t so big on guns. I can’t beleive they just hand them out to those dodgy-looking pudgy bastards that work “security”. I mean, cops, yeah, soldiers, sure. Some balding, goateed dumbass who could only make it into security work… no thanks. Protect bank money with a giant stick or a dog or something I say. ---
**Author:** ![Buck\_The\_Diver](https://avatars.discourse-cdn.com/v4/letter/b/ac8455/32.png) [@Buck\_The\_Diver](https://boards.straightdope.com/u/Buck_The_Diver)\ **Post date:** [March 31, 2003, 5:18pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/5 "2003-03-31T17:18:24Z")
> [@](#): > > \*Originally posted by Incubus \* > \*\*Ever heard of the Glock-9 pistol? \*\* According to the [Glock](http://www.glock.com/te_english.htm) website, there is no “Glock-9”. Or did you mean 9 mm? In addition, many parts in Glock pistols are made from steel, most noteably the barrel. ---
**Author:** ![Lissla\_Lissar](https://avatars.discourse-cdn.com/v4/letter/l/8491ac/32.png) [@Lissla\_Lissar](https://boards.straightdope.com/u/Lissla_Lissar)\ **Post date:** [March 31, 2003, 8:31pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/6 "2003-03-31T20:31:41Z")
Ceramic kitchen knives have been around for a while. I want one- they’re supposed to be incredible. It never occurred to me that they’d be good un-metal-detectable weapons. ---
**Author:** ![DreadCthulhu](https://avatars.discourse-cdn.com/v4/letter/d/db5fbb/32.png) [@DreadCthulhu](https://boards.straightdope.com/u/DreadCthulhu)\ **Post date:** [March 31, 2003, 9:00pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/7 "2003-03-31T21:00:51Z")
Ceramic knives are really nifty- they always stay sharp, but there brittleness limits their utility - you can’t use one as an emergency screwdrive, for example. ---
**Author:** ![Kalashnikov](https://avatars.discourse-cdn.com/v4/letter/k/2bfe46/32.png) [@Kalashnikov](https://boards.straightdope.com/u/Kalashnikov)\ **Post date:** [March 31, 2003, 9:12pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/8 "2003-03-31T21:12:51Z")
> [@](#): > > \*Originally posted by j\_kat\_251 \* > \*\*Sweet. I wonder how long entirely plastic/polymer guns will take to invent. Awesome. Smuggle dangerous weapons wherever you please. \*\* Not anytime soon, I think. Knives don’t have to withstand the heat and pressure that a firearm barrel does. Glocks and some other pistols have synthetic frames, and many rifles have synthetic stocks, but there are plently of large metal parts in them. They certainly can’t go through a metal detector (or x-ray machine for that matter) without being detected. When I used to work in the fiber optics business, we had ceramic scissors for cutting the Kevlar strength fibers in cables. They worked great unless the edges got chipped. ---
**Author:** ![ratty](https://avatars.discourse-cdn.com/v4/letter/r/ccd318/32.png) [@ratty](https://boards.straightdope.com/u/ratty)\ **Post date:** [April 1, 2003, 2:49am UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/9 "2003-04-01T02:49:26Z")
> [@](#): > > \*Originally posted by j\_kat\_251 \* > \*\*Sweet. I wonder how long entirely plastic/polymer guns will take to invent. Awesome. Smuggle dangerous weapons wherever you please. \*\* You _are_ joking, right? ---
**Author:** ![SlickRoenick](https://avatars.discourse-cdn.com/v4/letter/s/e68b1a/32.png) [@SlickRoenick](https://boards.straightdope.com/u/SlickRoenick)\ **Post date:** [April 1, 2003, 4:35am UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/10 "2003-04-01T04:35:16Z")
> [@](#): > > \*Originally posted by j\_kat\_251 \* > \*\*Sweet. I wonder how long entirely plastic/polymer guns will take to invent. Awesome. Smuggle dangerous weapons wherever you please. \*\* Didn’t John Malcovich make one in the movie “In The Line Of Fire” with Clint Eastwood? ---
**Author:** ![Tomcat](https://avatars.discourse-cdn.com/v4/letter/t/8e8cbc/32.png) [@Tomcat](https://boards.straightdope.com/u/Tomcat)\ **Post date:** [April 1, 2003, 2:52pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/11 "2003-04-01T14:52:10Z")
There actually was a company in Bulgaria (I think) that made a keychain that would fire ‘emergency flare cartridges’. Basically a little larger than a matchbox with two holes and a bar attached to a spring the would strike the primer on the ‘emergency flare’. Problem is that it just happened to also shoot .32 bullets. Hah! found an [article on it.](http://www.cnn.com/TRAVEL/NEWS/9805/06/keychain.guns/) -Tcat ---
**Author:** ![Wearia](https://avatars.discourse-cdn.com/v4/letter/w/13edae/32.png) [@Wearia](https://boards.straightdope.com/u/Wearia)\ **Post date:** [April 1, 2003, 5:30pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/12 "2003-04-01T17:30:56Z")
I’ve seen and played with those plastic knives. They didn’t cut as well as metal blades and they seemed fairly flimsy. You may as well use a broken CD as a weapon. ---
**Author:** ![Iteki](https://avatars.discourse-cdn.com/v4/letter/i/eada6e/32.png) [@Iteki](https://boards.straightdope.com/u/Iteki)\ **Post date:** [April 1, 2003, 6:02pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/13 "2003-04-01T18:02:47Z")
Tomcat, a bit like the cell-phone gun. They caught somone with one of these a while back [http://www.spybusters.com/jpeg/cell-phone-gun.jpg](http://www.spybusters.com/jpeg/cell-phone-gun.jpg) ---
**Author:** ![Susanann](https://avatars.discourse-cdn.com/v4/letter/s/7ab992/32.png) [@Susanann](https://boards.straightdope.com/u/Susanann)\ **Post date:** [April 1, 2003, 10:23pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/14 "2003-04-01T22:23:19Z")
It is illegal to carry a concealed knife in my state. I can (and do) carry a firearm, and I am licensed to carry a gun in about 25 states. My state does not issue permits to carry concealed knives, but we do allow people to carry concealed guns. Furthermore, I cant even “own” a switchblade knife in my state. I can own a machine gun(if I wanted to), but not a switchblade knife. Frankly, I dont see the sense in it. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [April 1, 2003, 10:41pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/15 "2003-04-01T22:41:53Z")
Every State has various & in many cases silly-assed laws about what edged weapons are legal. CA is amoung the worst. But even so- IANAL- it would seem that that knife is not illegal to carry or own in CA. YMMV Now- do NOT attempt to carry it onto an airplane or into a Courtroom- legal or no. At home in a display case- probably yes, even in areas where it might be illegal. In your pocket- legal or no- do NOT carry or claim to carry it for “self protection” or anything else that would indicate you admit it is a “weapon”. It is an unusual “letter opener”- “That’s my story & I’m sticking to it.” 😃 ---
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [April 1, 2003, 11:27pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/16 "2003-04-01T23:27:27Z")
Kinda big for opening letters isn’t it? You know letter openers are usually thin, that’s so you don’t rip the letter when opening zee envelope. I did have a pocket knife that looked like that & was sharpening it with a rock I found at the beach on the walk home. Well, a few minutes later I was surrounded by cops & they searched me & called in the Sgt. too & they let me go without saying anything. That’s Calif for you. funny, but it’s illegal to take rocks from the beach here. Guess they missed that one 🙂 So, astro, no sales to Iraq I hope. ---
**Author:** ![Gary\_Kumquat](https://avatars.discourse-cdn.com/v4/letter/g/4491bb/32.png) [@Gary\_Kumquat](https://boards.straightdope.com/u/Gary_Kumquat)\ **Post date:** [April 3, 2003, 1:04pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/17 "2003-04-03T13:04:34Z")
Even if you make a plastic gun, don’t you still have the problem of metal bullet casings? ---
**Author:** ![Tristan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tristan/32/18058_2.png) [@Tristan](https://boards.straightdope.com/u/Tristan)\ **Post date:** [April 3, 2003, 1:32pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/18 "2003-04-03T13:32:59Z")
In theory, you could get away with a real high-density plastic casing, but I’m not sure what you would actually make the bullet out of. ---
**Author:** ![3trew](https://avatars.discourse-cdn.com/v4/letter/3/13edae/32.png) [@3trew](https://boards.straightdope.com/u/3trew)\ **Post date:** [April 3, 2003, 4:08pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/19 "2003-04-03T16:08:45Z")
I don’t know what’s become of it lately, but back in the '80’s they were messing around with caseless ammunition, the bullet was set into a solid block of propellant. What you’d make the bullet out of is still a question, though. ---
**Author:** ![Revtim](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/revtim/32/1042_2.png) [@Revtim](https://boards.straightdope.com/u/Revtim)\ **Post date:** [April 3, 2003, 5:19pm UTC](https://boards.straightdope.com/t/undetectable-knives-legal-to-sell-and-carry/165379/20 "2003-04-03T17:19:48Z")
I got a free plastic knife with an order from a knife company years ago. Conceivably you could stab someone with it, but the cutting edge is crap. Like **Wearia** said, a broken CD is probably more dangerous.