Introduction: Conductive Paint

The goal of this experiment was to try to find an alternative to commercially available conductive paint. It is incredible stuff but expensive. I've read other Instructables like Makerboat's $1 Conductive Ink and IceCats' Paper Electronics. They helped me arrive at my own recipe, which uses only two ingredients but I think my testing is more reliable.

To make the winning recipe you need:

  • Graphite powder*
  • Acrylic paint
  • A jar with an airtight seal

To complete every test you need:

  • Elmer's Glue-All
  • Titebond III Wood Glue
  • Acrylic paint
  • Wire Glue (tm)
  • Graphite powder
  • 4 wooden toothpicks
  • 4 jars with airtight seals
  • Paper
  • Ohmmeter
  • 2 zip ties

*Be careful with graphite powder because inhalation can lead to respiratory problems.

Step 1: Glue-All and Graphite Sample

For the first recipe graphite powder was mixed with Elmer's Glue-All until the consistency was spreadable. Be careful when adding the glue because squeezing the bottle will shoot a blast of air into the jar and graphite powder will blow everywhere. The third picture illustrates this.

The ratio was:

  • 2 parts Elmer's Glue-All
  • 1 part graphite powder

The result was fluid but very thick. It could still be used as an adhesive.

Two lines were drawn with the toothpick. One thin line and one thick line. The toothpick was wiped off on the side of the jar and allowed to dry next to the lines.

Step 2: Titebond III and Graphite Sample

The second recipe was Titebond III and graphite powder.

The ratio was :

  • 1 part Titebond III
  • 1 part graphite powder

The result was fluid but not runny.

Two lines were drawn with the toothpick. One thin line and one thick line. The toothpick was wiped off on the side of the jar and allowed to dry next to the lines.

Step 3: Acrylic Paint and Graphite Sample

The third recipe was acrylic paint and graphite powder.

The ratio was:

  • 1 part acrylic paint
  • 1 part graphite powder

The result was slightly thicker than paint.

Two lines were drawn with the toothpick. One thin line and one thick line. The toothpick was wiped off on the side of the jar and allowed to dry next to the lines.

Step 4: Control Sample With Wire Glue (tm)

The fourth sample was commercially available Wire Glue (tm) from Think Geek. The Wire Glue(tm) needed to be stirred so another toothpick was used.

The Wire Glue(tm) was much runnier than the other samples so the lines were not as bulky. Less material being put down means a higher resistance since there is less carbon/graphite for conduction.

Two lines were drawn with the toothpick. One thin line and one thick line. The toothpick was wiped off on the side of the jar and allowed to dry next to the lines.

Step 5: Preparation for Testing

All the samples dried for five hours and were labeled.

Close-up pictures were taken to show the thickness of each sample. In order they are:

  1. Elmer's Glue-All
  2. Titebond III
  3. Acrylic paint
  4. Wire Glue(tm)

To ensure the samples were tested uniformly two zip ties were tightened around ohmmeter test probes. This ensured the probe tips were the same distance for each test.

Step 6: Testing Elmer's Glue-All and Graphite

Each sample of Elmer's Glue-All and graphite was tested with the fixed-width probes and recorded.


Step 7: Testing Titebond III and Graphite

Each sample of Titebond III and graphite was tested with the fixed-width probes and recorded.

Step 8: Testing Acrylic Paint and Graphite

Each sample of acrylic paint and graphite was tested with the fixed-width probes and recorded.

Step 9: Testing Wire Glue(tm)

Each sample of Wire Glue(tm) was tested with the fixed-width probes and recorded.

Step 10: Results

The acrylic paint is the most conductive material in this sample set when painted with a toothpick. The materials are commonly available and inexpensively. The acrylic paint cost $0.78 and the graphite powder cost $0.75. All prices are in US Dollars.

The advantage of the Wire Glue(tm), which has the next highest conductivity, is that it has a lower viscosity so it could potentially be used with custom pen nibs. Store-bought pen nibs were used with the Wire Glue(tm) in a different experiment but it was inconvenient to apply.

This build took me two days and one more to write these instructions.

I run a blog where I talk incessantly about the things I build, including an unabridged version of this project with videos that show the viscosity of the samples. There are other neat things there like a device that lets you hear temperatures and a keyboard you can use from inside your pockets.

Comments

author
The Gretz 69 (author)2017-08-07

i'm looking to shield the inside cavity of a bass guitar pick up area. i was looking at shielding tape but it's so expensive. So i was looking at shielding paint. same deal just tooo expensive.

So will this paint recipe work for what i'm trying to do?

author
24Eng (author)The Gretz 692017-08-07

I haven't tried it myself but it should work well. If you can wrap a pick-up in some painted paper first that could be a good test.

If this works, please let us know here so other people can follow your example!

author
tipigeon (author)2017-07-31

Now this is very very experimental, but would it be usable for metal plating using electrolysis for exemple?

author
24Eng (author)tipigeon2017-08-01

Are you talking about electroforming?
Some people have tried electroforming with this recipe but it doesn't hold up well in since acrylic paint isn't meant to be submerged in water. White glue would also be a bad choice. I have heard of people using silicone with a much higher graphite ratio but you will lose detail because it is so thick even if it does work.

I wish I had a better answer for you.

Let me know if I misunderstood your question.

author
tipigeon (author)24Eng2017-08-03

No you were spot on thanks alot for the feedback! Since what im gonna use is a bootleg DIY method i wont need to submerge it fully so i'll give it a go on a scrap piece when i can

author
JamieO34 (author)2017-07-31

Do you think using metal powders such as copper and aluminum powder would work?

Why is Graphene the ideal conductive material in making conductive paint?

Thank you so much!

author
24Eng (author)JamieO342017-08-01

Graphite powder is inexpensive and easy to buy. Some metal powders are flammable and harmful if they get on your skin. However, if you are careful they may provide better conductivity.

author
GreatdayB (author)2017-07-22

Im going to test this out. Ill use the acrylic paint and graphite and add the CO2, CUO2, and CH3 gans and see if it is more conductive then a normal nanocoated copper coil. It take some time, but I will report back. If anybody familiar with the magrav unit does this before me please post your results. Thanks.

#NeighborhoodAlchemist

author
GreatdayB (author)2017-07-22

Im going to test this out. Ill use the acrylic paint and graphite and add the CO2, CUO2, and CH3 gans and see if it is more conductive then a normal nanocoated copper coil.

author
GreatdayB (author)2017-07-22

Thanks for the instructable. I was wondering if this would improve the conductivity in a Magrav Generator if CO2 GANS, CH3 GANS, CUO2 GANS, acrylic paint and graphite was used to coat the coils. The generator already conducts without any outside source of electricity. So Im wondering if this would make the unit self powered.

author
patrick94gsr (author)2017-07-15

Where did you find graphite powder for that cheap? Everything I'm finding is either the tiny tubes for lock lubrication for $3-$4 or the larger jars/tubs for $10-$12 and up.

author
24Eng (author)patrick94gsr2017-07-17

I was fortunate enough to have a nearby surplus store with cheap graphite powder. I don't recommend pulverizing pencil leads because that would be messy but you can find inexpensive graphite powder on eBay.

author
AnandiB1 (author)2017-07-10

Did you create any projects using your winning recipe?

I'd like to use it as a trigger in a video installation

Any suggestions for a simple signal -> digital converter would be appreciated!

author
24Eng (author)AnandiB12017-07-11

I haven't used these recipes for any particular project but it was lined up for an electronic musical instrument which never panned out.

Can you tell me more about your video installation project so I can get a better idea of what you're trying to do? I have some ideas for a signal → digital converter but I want to know which one would help you the best.

author
AnandiB1 (author)24Eng2017-07-12

Thanks!

I'm thinking of having different surfaces of large cubes be either touch-sensitive or proximity sensitive, and trigger a chain of parameter / video changes in the software, Isadora (or potentially max/msp/jitter)

author
24Eng (author)AnandiB12017-07-13

My first inclination would be to use a Teensy (PJRC.com) microcontroller which can act as a MIDI device, keyboard or mouse depending on what your software needs to respond. Teensy boards support capacitive touch sensitivity so you shouldn't have trouble getting the painted sides of the cubes to respond to people handling them. What are you using to control your software now?

author
purveshg46 (author)2017-06-20

Which is the most conductive

author
24Eng (author)purveshg462017-06-20

Acrylic paint and graphite powder was the most conductive. All the results were compiled in step 10 if you want to know more.

author
DanielK341 (author)2017-05-18

What is the exact paint you used.

author
24Eng (author)DanielK3412017-05-19

It was Craft Smart brand paint. I believe the color was Carbon Black.

author
JohnI57 (author)2017-01-10

I'm doing a project that requires the paint to be conductive and while wet so paint can flow. Here are some results. Acrylic + carbon works best. I did 3/4 part carbon, 1 part acrylic paint and 1/2 part salt water. Even over long distances or drips its at 1.2k. Working well, doing some tests on how it looks dried, but not as important as having a proper conductivity while spilling :) Thanks for the help and advice!

author
CmeeC (author)JohnI572017-05-19

Salt definitely improves the conductivity, but I am a bit worried about it corroding the leads on longer terms.

author
24Eng (author)CmeeC2017-05-19

That's a good point.

author
24Eng (author)JohnI572017-01-11

Thanks for the recipe with salt water. I'm glad to hear you had success!

author
Nino Junel MakweinB (author)2017-02-26

Does the percentage of the graphite matter? I bought graphite powder that was 95%

author

I haven't encountered graphite powder that had a percentage rating. If that refers to the carbon content then 95% should be fine. Give it a try and let us know.

author
mjstation (author)2017-01-17

you can shop on ebay cheaper : http://www.ebay.com/itm/322377451443?ssPageName=S...

carbon conductive paint ; R=20 ohm , cheap ,waterproof when it is dry, the strong embedded in plastic, glass, metal. wood.etc

author
Hyshinara (author)2017-01-10

HAHA, YES!
I saw a video about conductive ink earlier, thought it was cool, but too expensive, so I thought: could it work if I ground up some pencil leads and mix it into something like acrylic paint?
Turns out that, not only it will, but that it might work better than the expensive stuff! :D
Thanks for the research! I'll definitely be trying this!

author
24Eng (author)Hyshinara2017-01-10

It's so fun to see people get excited about this geeky stuff. Good luck and happy painting.

author
Hyshinara (author)24Eng2017-01-10

Thanks! :)

author
ORGramps (author)2016-12-27

Hi, I am striving to make fractal tv antenna using conducting paint, but as you have noted, that is a very expensive product. I'm wondering if you or perhaps pmdillion (in the classroom) might have tried something like this. For information purposes, the designs I'm using each use four dipoles (that have repeated angular shapes). One design will use dipoles that are each 18" long (1/8" wide line). The other has dipoles that are each 10" in line length with 1/4" wide line. Other reading leaves me with the conclusion that although the resistance of each dipole may be a couple hundred ohms, the fact that this is a "very" low voltage application using the conducting ink/paint might work.

Thanks in advance for any assistance.

author
24Eng (author)ORGramps2016-12-28

I have never heard of anyone using conductive paint for an antenna so I hope you are on the brink of an amazing discovery! In college, I made a Yagi antenna for a class assignment and we used weather resistant aluminum. It never occurred to me to replace metal with conductive paint in an antenna. Resistance on the traces will be significantly higher than metal but I can see a lot of advantages, especially on the receiving end of things. I don't have much advice other than to suggest painting multiple layers for greater thickness. I'm eager to hear how this turns out.

author
katelyndawn89 (author)2016-11-11

hi there! I need conductive paint for the process of electroforming/electroplating (see:https://www.youtube.com/watch?v=c-mwoFDOLU0 – at 2:07 she explains what you use the graphite paint for) Do you think this would work for this process?

author
24Eng (author)katelyndawn892016-11-12

Several people have asked the same question. The consensus is that plating and forming will work but the high viscosity of the paint will obscure details. If you only want to make a simple shape without texture it should work well. If you want a very thin coat this will be a poor choice.
If you follow the testing procedure here and find a lower viscosity medium to carry the graphite then you will have the best of both worlds. And please tell us!

author
Hashy (author)2016-09-13

Hi Brian,

Thanks for doing the tutorial on this.

I was intending on using your mix of acrylic & graphite for repairing the demister/defogger array in the rear window of my car, which also doubles as the antenna for the car radio.

I'm wondering if you think that this mix would be suitable for the task? I'm thinking that perhaps the acrylic/graphite mix might melt & run from heating by turning the demister on. Do you think this might be a problem? Would one of your other mixes be more suitable for this application?

Worst case, I'll just buy the right stuff. It's just far more expensive then it need be...

Thanks,

Hashy (DD)

author
24Eng (author)Hashy2016-09-13

It was my pleasure, Hashy.
I think the acrylic/graphite mix would be a good place to start. These
ingredients aren't prone to melting so the heat shouldn't a huge issue
and as long as it conducts well it shouldn't produce much heat itself.
It might be prudent to put something inflammable under it for a couple
days in case something hot breaks off during use.

author
getriba (author)2016-07-02

hi! great info on the subject. I too make mix my own conductive paint. here's how I do it. I take water-based acrylic clear coats for flooring. I take three parts of acrylic clear coat to one part of water. Then I add about 6-8 parts of graphite. I always eyeball this as I work my way up to the consistency that I like. I always go a tad thicker than I want and then dilute it down with water again. I NEVER add any acrylic afterwards, I only add water and/or graphite. water is the key here, because you don't want too much of an acrylic resin in your mix and once the water evaporates it is literally gone completely out of your mix. too much acrylics to graphite increases the resistance. instead of acrylic clear coat (I think in US it is called water-based latex paint) you could also use an acrylic binder. usually the restoration supply stores carry it. the same that carry stuff for oil-painters and old painting restorers. you should thin that according to the instructions and play around a bit, because some binders can be highly concetrated and need to be heavily diluted. it is slightly different, but in essence both are similar processes. I have used that on my guitars for internal shielding. I get about 50K of resistance on a Strat but a factory Strat goes up to 140K with stock coating.

you always want your binder/paint/lacquer or anything else you are using in the smallest quantities possible but still allowing a good bond to the surface. I opt to use wood finishes instead of binders becase they have drying agents and additives for a hard final finish. it can be stored up to two years.

author
pmdillon (author)2016-03-17

Just got my package of acrylic paint and Microfyne...gonna mix up some paint during our afterschool class and let the kids paint circuits. Thanks for the instructions. Aloha!

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24Eng (author)pmdillon2016-03-18

Whenever I'm working on a project like this I hope that it ends up teaching kids! Thank you.

author
pmdillon (author)24Eng2016-03-28

We are just back from break and I'll mix up a batch for our class tomorrow...let them play with it and see what they make.

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tropicaliano (author)2016-02-17

Great idea. Great instructable, I've already thought about doing such conductive paint and run some experiments. You saved me some testing time. I´ll go with acrylic paint and graphite. Thanks for the instructable. Keep up the excellent work.

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24Eng (author)tropicaliano2016-03-18

I hope your experiments turned out well.

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Jatosin (author)2016-01-05

Do you think this paint could be used to do electroplating on plastics. Like a commercial conductive ink can.

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24Eng (author)Jatosin2016-01-06

A bunch of people asked early on in the comments so I tested this under water. Unfortunately it dissolves when submerged pretty quickly so it's no good for electroplating or electroforming. It's also very thick for that kind of process.

author
BrandonH61 (author)24Eng2016-01-16

Do you have any idea what graphite could be dissolved in so that it might be water resistant enough for electroplating?

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24Eng (author)BrandonH612016-01-17

I've heard people have made conductive silicone by combining equal weights of silicone caulk and graphite powder. I haven't tried adding that much graphite to silicone but I suspect it would be very viscous.

author
Johnsemi (author)2016-01-01

DUDE! You are my hero! I am working on some guitar projects w/ my son and conductive paint is very expensive, about $10.00 US an ounce. This is easy and DOABLE. Thank you!

author
24Eng (author)Johnsemi2016-01-03

Awesome! That's exactly the kind of thing I was hoping to do with this Instructable! I hope you post your guitar projects on Instructables.

author
mountaindogg (author)2016-01-02

We tried using graphite (275 mesh powder ~100% - http://www.amazon.com/gp/product/B00AIWVEU0?psc=1... mixed with enamel and could not get conductivity.

Any suggestions? Are we simplifying this too much? Does it have to be graphene?

author
24Eng (author)mountaindogg2016-01-03

I'm not sure if the enamel paint makes a difference. Can you do a sample of acrylic paint with the same graphite powder? The graphite powder link looks fine.