Bronze sea turtle creation process

[Jack]

This is the bronze casting process for my sea turtle sculpt (to see the sculpt click here)

Step 1- Mold:
2 piece silicone rubber mold with a fiberglass shell


Step 2- Wax Casting:
Molten wax is poured into the mold and poured out a several times until a thickness of wax is built up (approximately 1/4 IN.) thus making a hollow representation of the sculpture
Then the wax is cut into a few castible pieces (so that it can be gated from the inside) that will be welded together later


Step 3- Gating:
wax sticks and a pouring cup are attached to the inside of the wax positive and additional wax pipes are attached to the high points on the sculptures exterior to allow the air to escape as the molten bronze is poured in


Step 4- Investment:
A ceramic shell is created around the wax casting and gating system using a combination of ceramic slurry, silica sand and wire in many layers. After the built-up ceramic shell has dried it is put in a kiln (upside-down) to melt out the wax and harden the ceramic shell. Once the wax is melted out there is a negative space that the molten bronze will fill during the bronze pour.



Step 5- Bronze Chasing:
Once the bronze has cooled down (after the bronze pour) the ceramic investment is broken away revealing the bronze positive. The piping system is then cut off and the various pieces are welded together and cleaned up.


Step 6- The Patina:
The patina is the alteration of the bronzes color through the process of heat (propane torch) and application of chemicals (Ferric Nitrate, Cupric Nitrate, and Sulphurated Potash)

Once the patina is finished the sculpture is sealed with clear wax to protect the patina and give the sculpt a rich sheen


And that’s that- for this little guy anyway

[JesseBee]

Have to say it again. Wow. I didn't know what you were doing with the sculpy-clay before...I thought it was just going to end up gray with paint or something. What happens next? Can you make more than one of those turtles, or do you have to go through the process of molding it each time from the sculpy-original? Do you get to reuse parts? I'd imagine the silicone is reusable, no?

By the way, thanks for the great photos of the process; I know a lot of people don't like to give that stuff up... super cool!

[Jack]

Originally Posted by JesseBee

Have to say it again. Wow. I didn't know what you were doing with the sculpy-clay before...I thought it was just going to end up gray with paint or something. What happens next? Can you make more than one of those turtles, or do you have to go through the process of molding it each time from the sculpy-original? Do you get to reuse parts? I'd imagine the silicone is reusable, no?

By the way, thanks for the great photos of the process; I know a lot of people don't like to give that stuff up... super cool!

Once the silicone mold is created you can make hundreds of copies from the same mold (in wax at least). Plastics and resins are a little harder on the mold than wax. If you were to use a plastic resin or fiberglass you could probably get away with 30-50 pulls before you need to remold your master.

[jbl-fx]

That's amazing!

[Jack]

Originally Posted by jbl-fx

That's amazing!

thanks jbl-fx

[alienfactory]

Simply beautiful ! Thanks for sharing !

[Sylvok]

That is one insanely realistic looking turtle
really good job

[Jack]

thanks Sylvok

[eles]

Great job, it looks amazing, I really like it!

[boncingorangutan]

Extremely dynamic piece! Nicely done! did you cast and pour the bronze yourself or was it hired out to a foundry? If it was hired out to a foundry which one please? If not...you've got some mad technical skills!

[Jack]

Thanks
I hired out for the the most part but I did the patina myself.
The foundry I used is called "Mc 3 Foundry" in the los angeles (california) area.

[Addison]

Bronze metals helps in in providing variety of bronze Bronze conservation
metals,in variety of shapes and sizes these metals are also used in molding monuments like turtles.