Gluphite: Make a Key Chain Pencil

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Intro: Gluphite: Make a Key Chain Pencil

Gluphite is a fairly strong plastic made from glue. It can be used to make a small thin pencil that can be carried on a ring chain or in a wallet. It is cheap and easy to make and give as a gift.

The intro pic shows the pencil on a key chain.

STEP 1: How It Works

Gluphite is a simple mixture of Gorilla Glue and carbon graphite. It hardens into a fairly stout plastic that has some interesting qualities including working well as a pencil body and lead.

STEP 2: Materials and Mixing

Materials
Gorilla Glue or Elmers white glue
Carbon Graphite available as lubricating graphite from a hardware store.
Corn starch
100% silicone caulk
Plastic mixing cup and mixing stick
Measuring spoon


Mixing Gluphite
Mix 3 measures of Carbon Graphite by volume with enough water to form a thick paste. Add 2 measures of white glue and mix well. Spoon the mix onto some polyethylene plastic on a flat surface. Spread it out 3/16" to 1/4" thick at a diameter large enough for the pencil.

Unfortunately I have not found a way to get it to set up faster, so it usually takes 3 or 4 days to totally harden up. While drying, it will shrink and warp a bit.

Because it has so much carbon which strengthens the plastic, it also works quite well as a pencil lead. It is hard enough to not rub off on your hands but soft enough to make smear less lines on paper that are light but very readable.


STEP 3: Carving


It is easily drilled, cut, and carved using a Dremel tool. I used a sanding drum to smooth the sides and get the final shape.

While you can just drill a hole and hang it on the key chain, the pressure in a pocket could possibly crack the plastic. So, I made a flexible Oogoo loop to hold it on the keychain. I mixed 1 corn starch to 1 silicone caulk by volume and a dab of oil paint to give it color. I then rolled it thin between two layers of clear polyethylene plastic. I made it about 1/16" thick.

After an hour, I pealed off the plastic and cut the silicone to the desired size. See thumbnail pic.

I then mixed up a small batch of Oogoo just enough to fill the hole in the pencil to slightly overflowing. I used this to glue the loop on both sides of the hole by clamping it in place. The cured Oogoo glues incredibly strong to fresh Oogoo. For more details on using Oogoo see here: https://www.instructables.com/id/How-To-Make-Your-Own-Sugru-Substitute/

STEP 4: Other Possibilities


While not super strong, the gluphite has unusual qualities.

It is very smooth and slippery because of the lubrication graphite and could be used for small light duty mechanical bearings or sliding surfaces.

It could be used for making small cast parts.

It is conductive and the mix works well as a conductive glue.

The white glue can also be mixed with corn starch or fine sawdust instead of graphite to create a hard carvable plastic that can be colored with oil or acrylic paints.


15 Comments

couldn't you just crush pencil graphite into a fine powder and use that?
but the idea is so the stuff doesn't go everywhere and so that you can carry it with you...
I think Madrobot meant using the crushed graphite as a substitute for the store-bought extra-fine graphite, not as a substitute for the keychain.
ya, unconventionalartist is right. so it should work right?
unless you're wiling to sacrifice a coffee grinder for the project I would say no. You'd end up with way too manny lumps in your mix.
Well, you could use a mortar and pestle, and that would grind it up pretty finely.
Actually, I think that would just coat your mortar & pestle in a smear of graphite, giving you far less actual powder than you would get for your dollar than just buying the stuff.
Cool instructable!

I am also interested in this sentence: "The white glue can also be mixed with corn starch or fine sawdust instead of graphite to create a hard carvable plastic that can be colored with oil or acrylic paints." 

Does it mean that i can make low-cost customized casing or prototype with the above composition? Won't the corn starch decay? Will the product be waterproof?

Once again, thanks for sharing this nice instructable!
The starch does not decay, but the gluphite is only water resistant. It also deforms and shrinks as it dries.

For low cost prototypes and casings, I would suggest Oogoo which is waterproof and much easier to work with.
i say make a new design, cover it in some clear nail polish, and you got your self a cool surfing necklace
you know like those surf neckless.
What the heck your writing with the wrong hand... *tisk tisk tisk* *leftys*