Introduction: Translucent Cement DIY (+ Constellation Installation)
After discovering the cool-ness that is translucent cement and finding nepheron's Instructable, I started dreaming up ways to use this material combination.
I started playing around with nature-based themes and ended up making 56 cement panels embedded with monofilament. Each panel represents one constellation – the sum represents all constellations found in all seasons in the Northern Hemisphere.
I hung each panel on galvanized steel mesh spread taut across a metal pipe frame that rests 4 feet above a layer of sod. The final piece was set up at night on a city sidewalk under a street light as part of an art show. People could then lay on the sod and look up to see the stars :)
Materials for each cement panel:
- IKEA tupperware (for the mold)
- Fishing line and/or plastic rods (to transmit light)
- Armature wire (to hang the pieces)
- Oil-based clay
- Portland cement or high quality concrete
Step 1: Prepare a Flat Layer of Oil-based Clay
After a few experiments, I found that the best way to secure the monofilament in a pattern was to use a very flat layer of oil-based clay. To make the layer very flat, I used a marble rolling pin to create a layer slightly larger than my piece of tupperware and about .25 inches thick.
Step 2: Place Layer of Clay Inside Tupperware
Place the flat layer of clay into your tupperware container. Make sure that the clay fits snugly and hugs each side (otherwise the cement will find its way below the clay and can potentially ruin your mold).
I cut the clay layer based on the size of the tupperware opening, which is larger than the bottom, and then slid it into the tupperware so that it came up a bit on each edge. I then used a small knife to cut the clay closer to the bottom and used my finger to smooth out the sides.
Step 3: Transfer Pattern to Clay
To transfer my pattern to the clay, I copied the constellation onto a piece of paper and placed it onto the clay. I then used a pin to make a little hole in the clay. After removing the paper, I used the larger plastic rods, cut into 1-inch segments, to represent the constellation.
Step 4: Add Wire Hooks to Hang the Panel (optional)
Because I was planning to hang each panel, I added hooks to the mold.
Step 5: Fill the Remainder of the Mold With Monofilament
Fill the remainder of your mold with strands of monofilament. I used fishing line cut into 1-2 inch segments.
Step 6: Mix Cement and Pour Into Mold
Mix your cement with water into a slightly fluid consistency and pour it into your mold about 1/2 inch from the clay layer. Make sure to jiggle the mold a little bit to remove air bubbles.
Step 7: Let Dry (ideally Overnight)
Let the cement dry, ideally overnight, though you can get away with as little as 20 minutes depending on your cement manufacturer.
Step 8: Remove From Mold and Clean Up the Panel
Remove your panel from the mold after it has dried. It usually comes out pretty easily if you loosen the sides of the tupperware. The clay should also peal off relatively easily once out of the mold.
I then used nail clippers to clip each strand so that it lays relatively flush with the cement on both sides.
Feel free to also sand all the side (I didn't do this though).
Step 9: Hold the Panel to the Light
And smile as the light shines through :)
Step 10: And the Installation...
After hanging the panels and setting them up on the city street, I took a step back and loved watching people's reactions as they lied down.
More photos + info about the installation on my blog!

Participated in the
Concrete and Casting Contest
18 Discussions
5 years ago
Well now you have me re-thinking the design of my concrete fence column. Great idea of the constellations using concrete, and mono-filament vs a more expensive fiber optic. Have you played around with the length of the line and light brightness? Just curious because my column is fairly wide and I would need to have several inches of line to reach the outside. Thanks for showing your work.
Reply 5 years ago
Sounds like a fun project! I only used up to a few inches of monofilament during my experimentation but I assume that it will work regardless of the length - perhaps try a thicker line in your case. And share photos here :)
5 years ago
yes. that is awesome.
"fishing line" links directly to the amazon fishing line. that one was 60lb test. obviously you did some experimenting. did you like that line thickness? would you go smaller or larger?
Reply 5 years ago
I used both the fishing line I linked to as well as the thicker plastic rods that I linked to as well. It's really up to you and what project you have in mind, but I'd definitely recommend experimenting with a few different thicknesses to see what you like best before starting on your "final" project..
5 years ago
Flippin' awesome! This is very spiffy- I'll have a lot of fun with this~thanks for 'Instructing!'
Reply 5 years ago
Thank you!!
5 years ago
What a great idea!
I have a small project in mind that this would be perfect for.
Reply 5 years ago
Awesome! Definitely share photos here if you make your project :)
5 years ago
Fantastic idea. I've wanted a lighted walkway but had no funds for adequate glass block. This may do the trick with slight modifications. Thanks for the inspiration!
zapp
Reply 5 years ago
our local casino has the most awesome bar that is made from genuine agate slices, glazed over with a clear polymer and back lit. i realize that would be too expensive for your walk way but maybe it might give you some other idea.
Reply 5 years ago
Totally! If you do that definitely post a photo here :)
5 years ago
Wow, this is a really cool idea. I'm saving the transluscent cement idea for later :)
Reply 5 years ago
Thanks! :)
5 years ago
That is really good!!!
Thanks
5 years ago
Nice and imaginary
5 years ago
Well documented ible, and nice project ! Thanks for sharing :)
5 years ago
I didn't know about translucent cement cool.
This project is such a neat idea! Especially for a city, where there's a lot of light pollution and the stars are hard to see.
5 years ago
It would be awesome to lay down and watch