Introduction: HUGE Homemade Dinosaur Excavation Dig

About: Prop Maker and model maker working in the UK Film and TV industry. Credits include Star Wars, Doctor Who, Fast and Furious, The Batman Instagram: @petefieldingprops Youtube: P F Projects Facebook: Pete Fiel…

Here's an easy, simple project to impress your family with while at home.

Some cheap materials, very simple tools and a little time, can make for a wonderful experience for you and your kids.

Watch through the video, follow the steps, and give it a go!


Play sand - I used about 3/4 of a 25 KG bag from a DIY chain.

Fine Casting Plaster or Plaster of Paris - I bought a 10KG bag of casting plaster from eBay, and used about half.

Some Dinosaur "Bones" - I used a big "Dr Steve Hunters" 30" T-rex skeleton kit I got on eBay for £15.

Poster Paint (optional) - I just had these in my workshop, any water based paint will work.

A pair of safety goggles for every "digger" - YOU HAVE TO PROTECT EVERYONE'S EYES!

Some little "Geology" hammers - I bought two cheap Jeweller's Hammers from Amazon.

Some decorating paint brushes - I used a couple of our old brushes, but they are very cheap to but too.

Step 1: Preparing the Ground

Dig a fairly large, shallow hole in a bare spot in your garden or yard. The hole I dug was approx 2ft long, 1 ft wide and 6 inches deep.

Then add a thin layer of play sand into the hole. This will stop your "dig" getting stuck into your hole, if your earth is hard. It also adds a texture to the final "dig" cast.

Step 2: Make Up Your First Play Sand and Plaster Mix

The mix ratio is 1 part play sand to 1 part plaster to 1 part water.

I used a 2 litre jug as my measurement, but you can use any size container, just make sure you use the same amount of sand, plaster and water for each mix.

Add the sand and plaster into a bucket and mix it together dry, then add the water and mix it up thoroughly. I also added a little of the poster paint, just to add a bit of variation in the mix layers, but if you don't have any, it's not necessary.

As soon as you add the water, the chemical reaction with the plaster will begin, so you will have to work fairly quickly to get the mix into your hole and add your first layer of "fossils", before the mix becomes too thick and hard to pour.

If you add more sand, then the dig will be a little easier to excavate, if you add less sand, then it will be tougher and take longer. You can adjust the mix accordingly, depending on how old your "diggers" are, or how long their attention span is!

Step 3: Pouring the First Mix, Laying Some Fossils and Pouring a Second Mix

As soon as your mix is ready, pour most of it into your hole.

Then lay about half of your dinosaur "fossils" into the wet mix.

Once they are in place, make up a second batch of your sand, plaster and water mix, and completely cover up your first layer of "fossils".

Check back with the video at the start of the instructable.

Step 4: Second Layer of Fossils and Final Mix.

Next add the rest of your dinosaur "fossils".

Once the whole skeleton kit is laid into your "dig" , make up a third and final mix of sand, plaster and water.

Pour it over the rest of the skeleton, completely embedding it in the mix.

Sprinkle over a finial layer of dry play sand, and half bury the edge of your mix with some of the loose earth from the hole, just to rough up the edges of your cast a bit. This will help to make it look a little more "real" when you come to excavate.

Leave it overnight to cure and harden.


Now that the mix has hardened, flip over the whole cast, to reveal the underside.

Brush off all the loose earth and sand, then your ready to start your excavation.

Use the little jewellers hammers and paint brushes to slowly uncover the skeleton.

Remember to use the safety goggles, and have fun exploring the "dig site" , finding each piece, carefully uncovering it, and slowly piecing together your whole skeleton.

Again, watch through the video and have a go!

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