Halloween Pre-planning With Shapecrete - Tombstones

This is a ShapeCrete project from the Instructable/ Build Night at the Tech Valley Center of Gravity MakerSpace in Troy, NY.

This is the instructions for a basic tombstone to use for holiday decorations for Halloween. They are quick and easy to use and can be created a couple of days before. Or made ahead of time. They are light weight and easy to put in the ground.

Materials Needed:

ShapeCrete

Water

measuring cups/scoops

foam insulation sheets or Styrofoam

wire sign frames (I got mine used from a golf course after a golf tourney, or you can buy)

Mixing cup

stirrer

garbage bag

vinyl gloves

table protection of sheet plastic or newspapers

metal saw

hand saw for foam

We started with gray. You can use it as is or add dry pigment to the ShapeCrete to make it different colors. Since this is a tombstone, it is best to leave gray right now. ShapeCrete might be OK for those 12+ you still have to be careful. Put vinyl gloves on before working with it and don't breath it in. If concerned please use a face mask.

Now you can just do a rectangle tombstone like we did or make different shapes to change it up a bit to make the yard look like a real cemetery for Halloween. I started with the saw shown above. But you need to use one with no upper handle. See the next step photo to see the best type of saw to use. If doing various shapes you will have to cut away in sections to get any curves or odd shapes. You will need a vacuum or at least a broom and dustpan. This step makes a bit of a mess.

See the little blue bits. There are a lot of them when you cut. When you are done cutting you will want to pull them off your foam piece so they don't get messed up in the ShapeCrete.

I used old wire sign holders from golf course tee signs. After golf tourneys they just toss the signs and stands. You might be able to get them from them if you call ahead. Contact the grounds maintenance department for those.They are also the ones used for election signs. But don't snag those.After the primaries you might be able to get some stands from the non winners, they won't need them anymore.

Cut the sign stands in half using a metal saw. You will use one per tombstone. The cross bar at the bottom gives more support and keeps the tombstone balanced. You could just use thicker wires instead, but since I had these I used them.

Make sure your tombstones are wide enough for the wire stand. You will want to push the stand into the bottom to mark where the wires will go. Then take it out and one and a time slowly push the wire in to the stand the make the support holes. Once both holes are made, them push the stand into the tombstone all the way up the the crossbar.

Don't worry if you accidentally puncture through the front or back of the tombstone. Take the wire out and re-thread it through the foam again. To cover up the damage just use the other side. If both sides are needed then pull the snags out of the foam and fill it in with ShapeCrete.

Use measure out 3.5 parts of ShapeCrete. Smaller mixes are best so you don't mix too much and it gets hard. We used little shot glasses.

You add one part water and mix using your stirrer.

You use about 2-3 parts mix to pour into a mold, or 3-4 parts for clay use or for making tombstones.

When mixing you want to make sure you don't over mix. But while you are stirring it will suddenly just seem to all gel together that means the water has been absorbed by the ShapeCrete. You then add more mix or more water and stir until you get the consistency you want to make your project.

For tombstones, you don't want it too wet, but not too thick. You want to be able to spread it like frosting on a cake.

Take the mixture and spread it out over the top of the tombstone body. You can rough up the top with some sand paper if you want, but I did not do that. I just laid down a 1/8 inch or show layer and covered it.

Push a piece of garbage bag along the top of the tombstone to smooth is out and flatten out face of the tombstone.

This is the smoothed out face of the tombstone. You can leave it as is or decorate it with painting names and such on it. Or leave it as is. Then take the piece of garbage bag and put it under the tombstone to start covering the sides.

Just take the mixture in your hands and rub against the sides. Don't worry about the mess as long as it stays on the garbage bag.

To clean up the sides pull the edge of the garbage back up and push the left over mixture back onto the side of the tombstone. If you wait a few minutes it will stick really well as the ShapeCrete starts to set. Plus it will smooth out the sides.

Let it dry before flipping it over and finishing the other side. If no one is going to see the back you can save materials and just leave the foam showing.

When it drys completely go ahead and push it into the ground. It looks great. The kids will go crazy if you let them touch them. If you make a bunch you can have a whole cemetery in your yard.

They are lightweight, so when you are done you can store them for next year. I usually put them in reusable grocery bags so it easy to carry them up and down from the attic.

I will do another Instructables on how to decorate them. But make some basic models now and come back to my Instructables site to find out how.