# Can you build a complex electrical device, without metal? **URL:** \ **Category:** Factual Questions\ **Created:** [September 14, 2014, 11:29am UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469 "2014-09-14T11:29:56Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Ranchoth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ranchoth/32/1066_2.png) [@Ranchoth](https://boards.straightdope.com/u/Ranchoth)\ **Post date:** [September 14, 2014, 11:29am UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/1 "2014-09-14T11:29:56Z")
Occasionally, in fiction, you encounter an odd beast—a fairly complicated mechanical device, such as an aircraft or a robot, said to be constructed “without any metal.” Not even just non-ferrous metal. And yet, strangely, still have functioning electrical systems, such as lighting, or digital computers. Now, sadly, this field isn’t my strongest suit, so I’m left wondering: how complicated an electrical device _can_ you build without using metal, if any? Could you even build something on the level of a crummy flashlight, including the power supply? I’m sure that this is already more thought than any scriptwriter has ever put into the subject (“Oh, uh…it’s made of, like, plastic! And ceramics! Yeah, that’s the ticket…now where’d I put that cocaine?”). 'Anyone here with a higher grade brain care to take a crack at the subject? I haven’t gotten much sleep in the last couple of days, but I’m passably confident that I wrote that question _halfway_ intelligently. Well, maybe “passably.” ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [September 14, 2014, 1:05pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/2 "2014-09-14T13:05:12Z")
I believe carbon conducts electricity. I remember in grade school…or maybe it was on Mr Wizard, seeing someone conduct electricity through pencil lead (graphite). However, making anything out of that would be awfully brittle. You probably want to fine a way to permeate the graphite into something flexible like cotton, but non flammable like rubber. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [September 14, 2014, 1:11pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/3 "2014-09-14T13:11:30Z")
Yes, but it would be hard to do. There are a few substances that conduct electricity other than metals - Carbon, doped Silicon, some polymers. But none of them are as easy to use as good old copper. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [September 14, 2014, 2:11pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/4 "2014-09-14T14:11:03Z")
Conductive polymers are realistic for some things. Organic LEDs are the current best example. The idea that you might be able to create a reasonably complex device from them isn’t too unrealistic. But it depends upon what is meant by complex. High power handling or extreme miniaturisation (like modern integrated circuit) isn’t going to be likely, but devices that would have seemed like science fiction 30 years ago quite possible. One might note the the term “without metals” is open to interpretation. Does it mean no atoms of any metallic element? Or no metals in their metallic state? Or nothing at all in a metallic state? Most things that conduct electricity are “metallic” in that they have enough, and free enough, electrons to allow current to move. Not all metallic compounds are made of metals. But not all conductive states are metallic either. Some conductive polymers have the odd metal atom, but it isn’t in any sort of metallic state. ---
**Author:** ![Blue\_Blistering\_Barnacle](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/blue_blistering_barnacle/32/3386_2.png) [@Blue\_Blistering\_Barnacle](https://boards.straightdope.com/u/Blue_Blistering_Barnacle)\ **Post date:** [September 14, 2014, 6:02pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/5 "2014-09-14T18:02:08Z")
> [@Ranchoth](#): > > Occasionally, in fiction, you encounter an odd beast—a fairly complicated mechanical device, such as an aircraft or a robot, said to be constructed “without any metal.” Not even just non-ferrous metal. And yet, strangely, still have functioning electrical systems, such as lighting, or digital computers. > > Now, sadly, this field isn’t my strongest suit, so I’m left wondering: how complicated an electrical device _can_ you build without using metal, if any? Could you even build something on the level of a crummy flashlight, including the power supply? > > I’m sure that this is already more thought than any scriptwriter has ever put into the subject (“Oh, uh…it’s made of, like, plastic! And ceramics! Yeah, that’s the ticket…now where’d I put that cocaine?”). 'Anyone here with a higher grade brain care to take a crack at the subject? > > I haven’t gotten much sleep in the last couple of days, but I’m passably confident that I wrote that question _halfway_ intelligently. > > Well, maybe “passably.” When I read about these things in science fiction, unless they specify otherwise, I take “non-metallic” to mean “mostly non-metallic”. I’m thinking that the chief structural elements are plastic or graphite or glass or ceramic or … ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [September 14, 2014, 6:40pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/6 "2014-09-14T18:40:24Z")
There have been a lot of articles in the past few years about flexible, electrically conductive, nanocomposite membranes. If you had uttered the phrase flexible, electrically conductive, nanocomposite membranes back when I started my EE career I probably would have asked you how much coke you’d been sniffing. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [September 14, 2014, 7:30pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/7 "2014-09-14T19:30:02Z")
Salt water conducts electricity. You could use tubes of it, or maybe thin sticks or string permeated with it. There may not have been much research into good non-metallic conductors, since we have metal. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [September 14, 2014, 8:08pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/8 "2014-09-14T20:08:09Z")
carbon coated paper could produce a flexible conductor. carbon rod could be a higher current conductor. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [September 14, 2014, 8:41pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/9 "2014-09-14T20:41:58Z")
Is carbon considered a metal? ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [September 14, 2014, 8:46pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/10 "2014-09-14T20:46:29Z")
\*\*Can you build a complex electrical device, without metal? \*\* It’s very easy if the device doesn’t have to work. See other topics like wooden steam engines. ---
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [September 14, 2014, 9:39pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/11 "2014-09-14T21:39:21Z")
fiber optics would work if all you need to move around is data. and optics-based processors have been on the horizon for years, so metal-free computers isn’t that much of an exaggeration. You could even use it to convey light from a source (close to the battery) to more convenient locations on the body. I don’t know how you’d move power, though. Also, don’t most batteries contain a large percentage of metal? ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [September 14, 2014, 11:10pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/12 "2014-09-14T23:10:50Z")
> [@Senegoid](#): > > Is carbon considered a metal? It’s typically considered a non-metal. But depending on the chemistry, can also act as a metalloid (having some properties of both metals and non-metals). ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [September 14, 2014, 11:25pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/13 "2014-09-14T23:25:23Z")
> [@dstarfire](#): > > fiber optics would work if all you need to move around is data. and optics-based processors have been on the horizon for years, so metal-free computers isn’t that much of an exaggeration. You could even use it to convey light from a source (close to the battery) to more convenient locations on the body. > > I don’t know how you’d move power, though. Also, don’t most batteries contain a large percentage of metal? There are plenty of chemical batteries that wouldn’t have to depend on solid metals, assuming the anode/cathode could be fashioned from a conductive non-metal? But yeh, getting the flow of current in a device not comprised of metal seems a tad tricky. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [September 15, 2014, 1:36am UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/14 "2014-09-15T01:36:53Z")
> [@engineer\_comp\_geek](#): > > There have been a lot of articles in the past few years about flexible, electrically conductive, nanocomposite membranes. If you had uttered the phrase flexible, electrically conductive, nanocomposite membranes back when I started my EE career I probably would have asked you how much coke you’d been sniffing. You can still ask the question, and I wouldn’t mind. Where I work, they’ve been doing R&D on “electrically conductive composite materials” for many years. As far as I can tell, it’s only worthwhile in certain niche applications like LO aircraft skins and static dissipative stuff. It sucks as a conduit for energy transfer. For that you need metals. The only alternative would be a non-metallic, room-temperature superconductor. Good luck with that. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [September 15, 2014, 4:00pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/15 "2014-09-15T16:00:53Z")
Carbon nanofiber could serve all the same functions as copper, if we could make enough of it cheaply enough. Which we currently can’t, but that’s why this is science fiction. > [@](#): > > The only alternative would be a non-metallic, room-temperature superconductor. Good luck with that. Or a low-temperature superconductor and a nonmetallic cryo system. Or an environment that’s just naturally cold enough: Maybe this robot is a probe for exploring Pluto, or something. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [September 15, 2014, 5:17pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/16 "2014-09-15T17:17:11Z")
> [@Crafter\_Man](#): > > You can still ask the question, and I wouldn’t mind. Where I work, they’ve been doing R&D on “electrically conductive composite materials” for many years. As far as I can tell, it’s only worthwhile in certain niche applications like LO aircraft skins and static dissipative stuff. Out of curiosity, why would an aircraft skin need to be conductive? Wouldn’t that increase radar reflection? ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [September 15, 2014, 5:33pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/17 "2014-09-15T17:33:15Z")
> [@Really\_Not\_All\_That\_Bright](#): > > Out of curiosity, why would an aircraft skin need to be conductive? Wouldn’t that increase radar reflection? [In case of a lightning strike](http://www.scientificamerican.com/article/what-happens-when-lightni/). ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [September 15, 2014, 5:36pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/18 "2014-09-15T17:36:35Z")
I should have clarified: why does a _military_ aircraft need conductive skin? **Crafter\_Man** was referring to low observable planes. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [September 15, 2014, 5:42pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/19 "2014-09-15T17:42:53Z")
> [@Really\_Not\_All\_That\_Bright](#): > > I should have clarified: why does a _military_ aircraft need conductive skin? **Crafter\_Man** was referring to low observable planes. Sorry, missed that point. I don’t know about the effect on radar visibility. ---
**Author:** ![Capt\_Kirk](https://avatars.discourse-cdn.com/v4/letter/c/779978/32.png) [@Capt\_Kirk](https://boards.straightdope.com/u/Capt_Kirk)\ **Post date:** [September 15, 2014, 5:49pm UTC](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469/20 "2014-09-15T17:49:45Z")
> [@Really\_Not\_All\_That\_Bright](#): > > I should have clarified: why does a _military_ aircraft need conductive skin? **Crafter\_Man** was referring to low observable planes. I would guess to quelch EM transmission by making it a Faraday cage. Steathly in more ways than one. **Capt** [Next page](https://boards.straightdope.com/t/can-you-build-a-complex-electrical-device-without-metal/698469.md?page=2)