This project gives new life to old, broken crayons. Instead of having unused crayon fragments floating around and getting underfoot you can recycle them back into use.

I have two daughters, one is two and a half years old, the other is one and a half. The older one breaks crayons into pieces that are too small for the younger one to manipulate well. To combat this (and prevent all the broken crayons being swept into the trash) I melt and recast them.

*** Note if you are planning to make new crayons for a toddler please think about the size/shape of the finished product that comes out of the mold. You don't want to create a choking hazard for your kid(s).

Step 1: Materials Needed

1) Crayons - whole or broken

2 ) Molds - there are a number of ways to improvise here if you don't have suitable molds. More detail in step 3.

3) Heat source and vessel to melt the crayons. I have used the following 2 methods:

Heat gun and aluminum foil (you can substitute a hair dryer for the heat gun)
Stove and pan - to prevent my wife assaulting me I use a camp stove and soda can. A double boiler would be the preferred method. If you use a can you will also need pliers or another way to move a hot metal container.

In my experience the stove/pan method is more dangerous, messier, has more waste, and the results are not as impressive. I just present it as an alternative if you don't have access to a heat gun/hair dryer.

4) Materials to improvise a stand (if you use heat gun and foil). I have used:

Scrap wood and floral wire (used in this Instructable)
Empty soup can
Spring clamps

5) Safety

Fire Extinguisher
Proper clothing and footwear
Good ventilation
Bowl of ice water

6) Spring clamp & Razor knife (optional)

Step 2: Prepare the Crayons

Remove all of the paper wrappers from the crayons, and any debris that they may have accumulated during their tenure under the couch. Cat hair does not smell good when it burns.

For very small pieces it is easiest to just rip the paper off of the crayon. For larger pieces/whole crayons I find it best to slice through the wrapper with a razor and pull the entire thing off in one piece. You can hold the crayon by hand and do this, but if you are clumsy like me the chances of a razor cut are approximately 100%.

I use a cheap ($1 at the Home Depot near me) 2" spring clamp to hold the crayon steady, then just drag the knife across the wrapper.

Step 3: Get the Molds Ready

Silicone molds are the best option that I have found for this project, but you can easily improvise/make molds with stuff around the house.

In this Instructable I have used:

Blocks from my children's shape sorter (the yellow shapes).
Tube of rolled up cardboard and tape.
- Note- if you use tape use masking tape or some form of paper tape. I have found plastic tapes and their adhesive separate under the heating process and let go. This usually results in molten crayon pouring over the work area.
Miniature baking cup inserted into a small plastic cup (the cup is to give rigidity so the molten crayon stays put).
Lip balm lid glued into a plastic cup (makes a ring that the kids enjoy for 20-30 seconds prior to shattering it into 1,000 pieces).

In the past I cut up egg cartons to make an egg shaped mold, but my kids prefer shapes. Egg crayons are supposed to be easier for really young children to manipulate and may be worth trying if you have a smaller child.. You could probably drill a hole in a plastic Easter egg for a better result with less work.

The cardboard tube is a single use mold, and I just peel it away from the recast crayon.

For all of the plastic molds you will want to lubricate them so you can get the crayon out. I give them a light coating of coconut oil because that is what I had on hand. Pam or similar cooking spray would probably be easier to apply, especially if there are any tight curves/corners. Since children like to put things in their mouth be sure to use a food-safe oil.

If you have access to a 3D printer- I do not :( - the sky is the limit.

Step 4: Step 4: Making a Foil Funnel (only for Heat-gun Method)

The dimensions of the funnel you use can be modified based on your preferences. I usually prefer a smaller funnel and put 1 or 2 crayons in it at a time to keep the colors in the finished product somewhat segregated. If you want the colors to run together more a bigger funnel will let you to jam more colors in at a time. I also cast mostly small items. Bigger projects would need more crayon and a larger hopper would help.*

My foil is 12" wide. I generally use a 12" x 12" (30.5 x 30.5cm) piece for a larger funnel or a 12" x 6" (30.5cm x 15.25cm) piece for a smaller funnel.

If using a 12" x 12" (or other square piece) Fold it in half twice. This should result in a square piece 1/4 the size of the original piece. If you want a particularly thick/rugged funnel you can halve it twice more. It will be 1/4 the current size and have more layers of foil to add structure.

If you are using a 12" x 6" (or other rectangular piece) fold it in half once to make the piece roughly a square. Then fold twice more as above to produce a square 1/4 the size of the original.

Now you will need to look at the four corners of your square. You are looking for the corner that is made up entirely of folds. There should be no raw edges present. Cut off just the tip of this corner.

This is where your molten crayon will leave the funnel and pour into the mold. If you make it too big entire pieces/crayons will fall through without melting. Start small and gradually increase the size of the hole if you need to.

Now you will just want to form your funnel into a funnel shape. I just mold it by hand. Try to make sure that your opening is directly centered in the bottom of the funnel so your liquid ends up where you want it to.

* Note: The crayons shrink when they cool. The larger the mold the more likely it will be distorted during the cooling process.

Step 5: Step 5: Building/Improvising a Funnel Station

We need to devise something that can hold our funnel above the mold and allow us to apply heat to it. I have used a number of things that I had lying around:

Soup can - requires mold be fairly small, and it is a huge pain to get the mold back out. Good option if you want to layer colors in the mold though, because you can put the entire thing aside to cool.
Tower of 2" spring clamps - I clamped the clamps together and then used a small 3/4" clamp to hold the funnel to the tower.
Scrap wood and piece of gardening wire - the method I used in this Instructable. This has been the best solution so far because it was easy to put together with some scraps I had lying around and is more readily adjusted/customized to allow different heights/widths of molds.

I assembled this stand by grabbing a pair of wood scraps that were an "L" shape and the same height. These support everything structure.

I twisted some wire into a loop and stapled it to the wood braces to suspend the funnel between the braces.

Using wire was beneficial because I could adjust the width between the wood braces. This let me easily accommodate different molds and funnels.

It was also a simple matter to take it back apart and return the parts to the scrap bin for later projects.

I don't have photos of the construction steps, but hopefully the pictures of the complete apparatus will make sense. It is just a piece of wire stapled to 2 boards. The last photo shows a tin can being used to hold the funnel.

Step 6: Step 6: Get the Mold Ready

If you are using a silicone mold all that needs to be done is to place it under the funnel.

If you are using a plastic mold be sure to lubricate it (using food safe oil), then place it under the funnel.

I like to look through the funnel to make sure everything is aligned properly.

If you will be switching molds, or moving from one cell to another in the same mold now is the time to plan how you will do this.

Any mold that you use will be hot to the touch. If you burn yourself moving it you may reflexively spill/fling molten crayon causing further problems.
Silicone molds flex, which can lead to molten crayon pouring out.

I use a scrap piece of wood to put under loose molds (i.e. the yellow shapes) so I can move the wood forward/backward to remove one mold from the heating area and introduce a new one. With silicone I slide them along the work space, but I am careful to move them slowly and use gloves or pliers to prevent being burned.

Step 7: Step 7: Add the Crayons and Let 'er Rip

During this stage you will be manipulating molten wax that runs freely and have a number of hot surfaces during the process. So some safety precautions:

Wear appropriate clothing and shoes.
Be mindful of where molten wax will run to if it is spilled. Is the work space level? Are there items/barriers that will direct the flow, etc.
Keep a bowl of cold water nearby. If you get scalding hot wax on your hand it will continue to burn the area until it cools. The best thing to do is dunk your hand in the water and pull of the wax as soon as it hardens enough to be removed (in my experience a couple seconds in an ice bath and it comes off).
Be aware of the potential fire hazard. Keep a fire extinguisher handy. Crayons are made of paraffin wax., the same thing candles are. If something gets heated to the point to combustion you can have a real problem real fast.
Make sure the area is ventilated. The last remnants of the crayons during the heating process can sometimes burn off, especially if you use a higher heat setting on your heat gun.

Now let's get to it.

All you need to do is add crayon(s) to the hopper of the funnel and apply heat. I move the heat gun around to try and heat everything evenly.

Often times the crayons will begin to melt, but nothing will run out of the funnel. This is fine, just keep applying heat. Usually a larger piece of unmelted crayon has blocked the opening. Once everything is heated enough it will liquefy and the melted crayons will run.

DO NOT try to poke around in the funnel to open it up. It is easy to dislodge it from the holder, or shred the foil it is made out of. At minimum you get a mess, but you can easily be burned doing this.

Keep an eye on how full the mold is versus how much crayon remains in the funnel. When the mold is getting close to full stop adding crayon and/or remove the heat so the crayon stops running freely. I find it is better to have a mold somewhat under filled than somewhat over filled.

Once the mold(s) are full set them aside to cool. If you want to expedite the process you can put them in the freezert.

After the crayons have cooled and solidified pop them out of the mold and you are all set.

Silicone molds more or less turn inside out. And the crayon pops right out.
For hard sided molds I turn them upside-down and smack them on the table a couple times to loosen the crayon up, then it should slide out with a little teasing.
As mentioned previously, cardboard/paper molds peel off.
- The inner layers of paper will likely be saturated with colored wax. You may find ways to repurpose this waste. I use the ugly wax impregnated paper as fire-starting material. My wife uses the prettier pieces in art projects with the kids.

Steps 8 details how to use a stove and pan instead of the heat gun/funnel. If you used the heat gun method you can skip to Step 9 for tips.

Step 8: Using a Stove and Pan (skip If Using Heat Gun Method)

As mentioned previously I would avoid the stove and pan method and stick with a heat gun, if possible. In my experience there are a few drawbacks to using the stove:

It's more difficult to clean up.
If you have a gas stove the fire risk is greatly increased.
There is more waste from crayons coating the pan.
It is easy to accidentally mix all the molten crayon into a nasty brown color. If you are mixing hues of one color only (i.e. different types of blue) it isn't nasty, but still a solid color and far less attractive than a mixture of colors/hues in my opinion.

If you have a double boiler, or two pans that can nest inside one another definitely use that. It will reduce your odds of burning down the house. I have been banned from using kitchen pans for experimentation (we won't go into details) so I resorted to an empty soda can over a camp stove. This is more dangerous and I definitely do not recommend it.

This is a fairly straightforward process. You place crayons into the pan, then put the pan over a heat source. Unless you have a good reason not to (setting isn't available, in a rush) I would advise to use the lowest heat setting you can find to melt the crayons. Less chance of a fire, less crayon burning to the sides of the pan, etc.

Once the crayons have melted you will carefully pour the liquid into the mold(s) that you are using.

*** If you are melting crayons in a single pot over fire (as I was in the photos) after your first pour everything becomes more dangerous. You now have a flammable liquid running down the side of your pot (or can, in my case) that is being put over fire. Things can (obviously) go wrong from this point forward if you are not careful.

Once the mold(s) are full set them aside to cool. If you want to expedite the process you can put them in the freezer for a bit.

After the crayons have cooled and solidified pop them out of the mold and you are all set.

Silicone molds more or less turn inside out. And the crayon pops right out.
For hard sided molds I turn them upside-down and smack them on the table a couple times to loosen the crayon up, then it should slide out with a little teasing.
As mentioned previously, cardboard/paper molds peel off.
- The inner layers of paper will likely be saturated with colored wax. You may find ways to re-purpose this waste. I use the wax impregnated cardboard as a fire-starter.

Step 9: Tips

There are 3 main variants of color pattern that you can make:

Solid Color - a single color (was that necessary?)
Layers of color - imagine it like a rainbow, with defined segments of a specific color
Swirl - all of the colors swirl together throughout the end product

Most of the crayons I make are what I call "swirl" because my children them and it is easier to do than layering.

When the "swirl" crayons are in the mold, but still liquid you can use a toothpick to introduce patterns or spread colors as you like.

To make a layered crayon:

Put a quantity of one color in the mold.
Let it cool.
Add the next color.
Let it cool.
Repeat until the mold is full or you have all the colors you want.
Recommend cooling in the freezer, because this TAKES FOREVER.

This process is better for large molds because the cooling takes place incrementally so you don't end up with the shrinkage you otherwise would. If you decide to layer crayons I have found that it is best to heat up the top portion in the mold so that it is nearly to the point of melting. Then when you add the next layer they wont mix and swirl together, but both layers are liquid enough to let them laminate and the crayon is less likely to fracture between layers.

If you are able to tilt the mold it will move the layers off axis, which I think looks better.

If you have a thrift store nearby drop in sometime if you need pans to make a double boiler, or crayons. The store near my house occasionally has giant bags of crayons (new and broken) for $1. Pots and pans are usually priced about the same. If you need a hair dryer you might find a deal on that as well.

If you don't have a hair dryer or heat gun (and you live in the U.S.) you might look into the Harbor Freight heat gun. I have no affiliation with Harbor Freight, and I know they are much maligned. I am careful to research anything I buy from them, and the heat gun had good reviews. It costs about $9 when it is on sale. I have had mine for over a year and use it fairly often (a couple times a month, at least) and have had no problems. To be safe, I do make sure that it is never left plugged in.