Introduction: Recycle Plastic Beads Into Dice

About: I'm an engineer and a dad who has a love for designing and making toys, STEM projects and anything electronicy.

At the moment, I'm designing a fantasy board game and this got me thinking about the dice that'll play a major part in combat. There are going to be a range of different dice, but rather than just buy all the parts off the web, I decided to try and make my own. After all, you can then personalise the colours, spots, numbers, number of sides. Well, everything! If I could reuse something I already had in the house, even better!

With that in mind, I set out to design my own home-made dice using plastic beads. I discovered, it's really not that hard!

Step 1: Step 1: Collecting and Preparing Your Materials

To make home-made dice, you'll need the following:

Mould
- A cereal box, or plasticised cardboard of some sort
- Sticky tape
- Ball-point pen
- Lolly/popsicle stick
- Blu-stuff 2 part liquid silicone (or another kind of pourable silicone)

Dice
- A die you want to cast in the shape of.  To keep it simple, I started with a D6 (6-sided die)
- Coloured plastic pony beads (sparkly, transparent, opaque, these all work nicely!) - I had a bag lying around gathering dust
- A hammer
- Alternatively, you can use Hama beads, these also work well
- Tip-Ex, a Sharpie or other fast-setting liquid to mark out the numbers or spots on your finished die
- An oven

Step 2: Step 2: Preparing Your Mould

Take your die and place it on the side of the cereal box (or other plasticised card), rough side up.

Draw a box around the die with a little space either side for the silicone to flow into.  Now create a cube net around it by drawing squares off the edges of the box on each of its 4 sides.

Cut around the whole shape and you should have what looks like a cardboard '+' sign.

Next, use the tip of a ball-point pen and a ruler to score a line along the lines you've drawn to create score marks.

After that, fold the edges of your shape in to create an 'open top' cube shape, making sure the plasticised side is facing in.  This is so that the silicone peels away easily once it's cured.

Use sticky tape to join all the sides together, making sure that all the sides are gap-free.  You don't want your precious silicone leaking out while it cures!

Step 3: Step 3: Mixing and Pouring Your Silicone

If you're using Blu-stuff liquid 2-part silicone, you'll want to measure out equal quantities of the white and blue liquids into a plastic pot.

Next, use a lolly stick to stir the 2 liquids for around 30 seconds or until they're fully mixed and you can't see any darker blue or white liquid.

Place the die into your cardboard mould in the centre, least detailed face facing down, ensuring there is a gap between the die and the cardboard walls. Your least detailed face will need fine etching or spotting later on, but we'll come to that in time.

Now, take your pot of mixed silicone, pinch the pouring edge if you can (to create a finer flow) and pour into a void next to your die.  Ideally, so that the silicone pours onto the bottom of your cardboard box.

Pour slowly and patiently, as this will help prevent air bubbles and you want the silicone to fill every dimple, spot and dented number on the side of your die!

Keep pouring until the top of your die is covered by a good couple of millimetres.

Allow the silicone to set up for ~15 minutes and you should be able to remove your die, leaving you will your oven-proof silicone mould!

N.B. The cured silicone in the photo is from my original cardboard box.  I cut away the original and decided to make a new one for the photo!

Step 4: Step 4: Preparing and Adding Your Plastic to the Mould

Left over pony beads are great for several reasons.  First, because when you buy in bulk, they are pretty cheap.  Secondly, they also come in a range of transparent and opaque colours, so you can create quite exciting mixed colour effects with your dice!  I used a bag I had lying around the house.

This is a good time to turn on the oven to gas mark 7 / 220 degrees C / 425 degrees farenheit as it'll take a while to prepare your beads!

Separate the coloured beads you want for your finished dice (in my case, about 15 green beads) and use a hammer to carefully tap them on the round edge, rotating as you go until they shatter into smaller pieces. When using smaller pieces of bead, in my experience at least, this helps create fewer air pockets in the melted plastic, and reduces the visible 'bubbly' effect you get in transparent beads.

After that, tip in enough pieces of bead so they reach the top of the mould and place the mould on a metal baking tray, open side up.  Close the oven door and open all the windows in the kitchen - as the plastic melts, it will give off some gases you don't want to be breathing in.

Set a timer for about 20 minutes and go write a bit more lore for your board game.  In another room!

Step 5: Step 5: Topping Up the Plastic

When the buzzer goes off, you should notice the plastic has melted together and that the level of the plastic has lowered.  This is because the molten plastic has flowed into the air gaps around the solid pieces.

Use oven mits or a layered tea towel to take the metal tray out of the over and place it on the hob - or another heat-proof surface.

Now, take some more of your pieces of plastic bead and sprinkle them on top of the molten plastic in the mould until you have filled the mould again.

Return the metal tray and mould to the oven (same temperature) for another 15 minutes and return.  Repeat this 2-3 times or until the mould is filled with molten plastic.

Step 6: Step 6: Setting Up Your Die

Once your mould is completely filled with molten plastic, turn off the oven and use oven gloves or a layered tea towel to lift out the tray with the mould on.

Set up a cooling rack and use tongs to lift the mould off the metal tray and onto the cooling rack.

As the metal tray will retain its heat for a while, the cold cooling rack will help silicone and plastic to cool down more quickly.

Design a few weapons or treasures for 10-15 minutes and your die should be cool enough to handle.

Ease aside the silicone on top and push from underneath with a finger.  Your die should just pop out with a bit of encouragement!

Step 7: Step 7: Adding Details (spots and Numbers)

Hurrah!  You should now have a home-made plastic die.  A couple of rolls showed the die to be well balanced and rolled a range of different numbers.  All that remains now is to add details so you know whether you've killed that dragon or merely annoyed it.

With your blank side (top side of the mould), you've got a couple of options.  Firstly, you could use a 3mm drill bit. rotary tool or engraver to carve a spot/number into the plastic.  Secondly, you could just draw on the relevant spot/number.  In this cas, i just spotted on some Tip-Ex.

I found different liquids worked well to add spots or numbers.

For the green die, I used Tip-Ex as it contrasted well with the bright green plastic and also dries to a hard finish.  The only downside is it tends to flake off non-porous surfaces.

Alternatively, Sharpies work brilliantly, using a bullet tip pen to colour the inside of spots, or a fine liner to colour in indentations of carved numbers.

Well, there you have it.  A home-made plastic die with fairly little effort and made from most recycled materials which were just lying around my house. Plus, there's been plenty of time to write a bit more of that board game you've been working on!

I've included a photo of a clear transparent die I made using clear whole beads, but you can see the issues I had with air bubbles!  Spots were filled using a gold pen.

In reflection, I have plans to make other dice for the game: D10, Percentile, D20 and D4s.  I may update or post a new instructable detailing this in the future.

I'll leave you to have fun casting your own dice and remember to keep those windows open or work in a well ventilated area!