Check out the build on Instructables
I love the Legend of Zelda series. To date, my favorite is Breath of the Wild. One of my favorite parts of the game was the Goddess Hylia statues. They all looked so adorable, round, and huggable. So much so that I wanted one for my front yard.
I didn’t just want to 3d print one and paint it to look like stone… I really wanted to make it out of stone. Concrete to be exact. This meant I had to learn a bunch of new skills like mold making, plaster casting, and concrete mixing to make something adorable for my home 🙂
**Fair warning. This was very complicated and I learned as I went. I am by no means an expert in any of these processes. If you have better ways to do ANY OF THIS, I would love some tips!**
VIDEO ON OUR BUILD PROCESS WILL BE PUT IN HERE SHORTLY.
This project has a long supply list but a lot of it is stuff you have around the house.
- CR-1O 3D Printer (any3dp
- Computer with Cura
- PET-G Filament
- Pliers and Side Snips
- Sandpaper – 80,120, and 240 grits
- Blue Shop towels
- Kitchen Scale
- Disposable gloves (3 pairs if you’re working alone, 6 pairs if you have a buddy
- Plastic cups
- Tongue depressers (mixing sticks)
- Chip brushes (3 if you’re working alone, 6 if you have a buddy)
- Universal Mold Release
- Plaster Strips – 2 orders. We used one for each side
- Smooth-On Rebound 25 Brush On Trial Unit Platinum Silicone Moldmaking Rubber
- Quikrete Ready-to-Use Concrete Mix 60 lb.
- Collander – for sifting SOME of the aggregate out
- 2 – 5-gallon buckets
- one extra-large tub
- Pea Gravel
- Plastic Wrap
Step 1: 3D Print the Goddess
On Thingiverse, I found the model I wanted to print of the Goddess
- Within Cura, set up the print so she is about 12″ high x 10″ wide x 7 deep with a 10% INFILL.
- Using Octoprint, send the files to the CR-10.
- To set up octoprint– we followed this instructable
- The print took 45 hours and 13 minutes
- The printed was loaded with PET-G Filament from Hatchbox which we keep in a dry box at all times.
Step 2: Prep the Surface
After waiting fortwo days and hoping that nothing with you print or power fails, you will have a complete model. We decided to make the model out of PET-G because it is more sandable than PLA.
- Start by removing all the support material.
- Sanded the entire surface using 80, 120, and 240 grit sandpaper. You are not going to be able to remove all the lines but you will be able to get it to a much smoother point.
- Whip her down with a clean, damp rag
- Using something like XPS foam or wood, create a base for the model to be hot glued down too. Add walls around the edges of that base. This will allow the silicone to have a place to pool.
- Spray her down with a little bit of SmoothOn Universal Mold Release
Step 3: Make the Silicone Cast
Using GLOVES andRebound 25 start creating the mold. This silicone is a 1-1 ratio by weight or volume and there will be enough for three layers.
- Using a kitchen scale, measure the two parts ~5 ounces at a time.
- (With the 16-ounce trail sizes, you will get 3 successful layers out of this.)
- Pour Parts A and B into their own individual cups for weighing.
- When the cups matched weight, pour B into A and mixed until the color was smooth.
- Pour the mixture into a clean, new cup and mix again. There can be a lot of un-mixed portions in the bottom of the cup.
- Using a chip brush, start brushing on the mixed silicone.
- (There is a short enough pot life to the Rebound 25 where you should start moving quickly.)
- Work to get a thin layer applied everywhere
- Make sure places like the undersides of the wings get enough.
- Silicone will drip off and that is fine. If the silicone is still brushable, brush it back a bit. If you see thin spots right away don’t worry you will be repeating this process two more times. Just continue to backfill on the next two passes.
- Wait one hour between layers and repeat until you are out of silicone in the trial size containers.
- use a new pair of gloves, brushes, and cups for each layer
Step 4: Add the Plaster Structure
After letting the Mold cure for a day, it is time to start the plaster cast. DO NOT REMOVE THE 3D PRINT FROM THE MOLD YET.
- Cut up your plaster sheets into different sizes. We did a handful of different shapes but found that the smaller thinner shapes worked best for getting into the nooks and crannies.
- Using a clean bucket of water and one long thin sheet of the plaster strips, create a middle point on the mold. (photo1)
- Working on only 1 side, complete cover the pieces in plaster strips. Avoid the wings but leave a void (almost like the armpit of a t-shirt) for her wings to slide out.
- Let the plaster set for about 2 hours. (photo 2)
- After the plaster has had time to set, using a damp blue shop towel, line the seam where the two plaster pieces will meet. This will allow the two pieces to separate later.(photo 3)
- Repeat the plaster process for the unfinished side and let dry for another day. (photo 4)
Tip – We tried to follow a video that Bill Duran at punished props put out with I Like to Make Stuff’s Bob in which they molded Bobs face and applied a two-part plaster cast. We messed up on the wings because they are thicker on the outside than on the inside so when the plaster dried we were unable to remove the mold without cutting the plaster from the wings.
When recreating this, do everything we did EXCEPT plaster the wings. Give her a little tank top instead and you will have no problem removing her from the plaster. If you have a better way to create a plaster cast around these wings, we would love to know!
Step 5: Set Her Free
Its time to pull our little lady out!
- Remove her from the attached base. (photo 1)
- With some gumption, Pull the plaster cast from the seam near her arm area and remove each side.
- When recreating this, do everything we did EXCEPTplaster the wings. Give her a little tank top instead and you will have no problem removing her from the plaster. (photo 2)
- If you have a better way to create a plaster cast around these wings, we would love to know!
- Let the plaster mold sit apart for a few hours to fully dry on the inside.
- Starting from the bottom of the silicone, carefully cut a zigzag pattern up her back and de-mold the 3d print from the silicone.(photo 3 + 4)
Step 6: Put Her Form Back Together
Now to put her right back together
- Piece the plaster mold back together and hold the parts in place with two large rubber bands(photo 1)
- Put a piece of Masking tape inside on the plaster cast where the zigzag cut on the silicone will line up.
- This is to keep the plaster cast clean incase any concrete leaks out the crack
- Insert the silicone mold and into the Plaster cast.
- This will be a loose fit so just try to line up the zig-zag as evenly as possible The concrete will hold this all in place.
- Spray the inside of the silicone with mold release
- Add some plastic wrap around her plaster cast. (Photo 2)She will be outside for a night and plaster doesn’t like water. This will just help with the dampness.
- Place her headfirst in an extra-large tub that has been filled about 1 inch with Pea Gravel
- We used a huge stockpot but any large container will do
- Start filling pea gravel around her head and body up until the gravel is holding her upright but still allowing you full access to the wings.
Step 7: Pour the Concrete
Before we add water, we have to remove some of the aggregate. As you can see in Photo 1, too much aggregate causes a chunky body and a smoother mixture.
- Using a colander, sift the Concrete mixture into a 5-gallon bucket. Dump the aggregate into a different 5-gallon bucket.
- Continue sifting until you have used roughly half the bag.
- Add about half of the aggregate you removed back into the sifted bucket.
- Add and mix water until the mixture is a thick pudding-like consistency.
- Use a stick, a trowel, or your hands to mix this up. (photo 2) If you use your hands, be sure to clean them off IMMEDIATELY.
- Make sure to scrape the bottom of the bucket to ensure everything was mixed properly.
- Start adding into concrete to the form. (Photo 3) Make sure with each addition that you take time to tap it down.
- In Photo 1, we failed at taping down around her arms which also led to the chunkiness, so take your time and pat it all down
- As you start to fill in the wings, surround the wings in Pea Gravel to maintain their shape.
- Since we didn’t have a proper plaster cast around those wings, we wanted to make sure they wouldn’t inflate too much. The pea gravel acted as a cast and prevented the wings from expanding
- Fill her body completely with concrete and let it sit in a safe place overnight.
- We put one of the 5-gallon buckets over her incase it rained.
- Let her sit for at least 10 hours
Step 8: Put Her Somewhere in Your Yard
After waiting for the concrete to set, remove her exterior shell and take her out! I love that you can still see some of her 3D print lines and the infill marks.
This was one of the hardestprojects we have done. We knew nothing about 3d silicone mold making, plaster casting, or concrete but we learned a TON and have a successful Goddess Hylia in our front yard!
She will be decorated for every holiday. She is perfect and I love her.
Please, again, if you have tips or tricks on how to do this better, we would love to know. Especially if you have a better idea on the paster cast.
Have fun and go make something awesome!