Hello! This past week, I learned how to use alginate and rockite to make a mold of my fingers.

To create my alginate mold, I followed the recommended ratio of 1.5 ounces of alginate to 6.75 ounces of water, which was appropriate for casting two fingers. I mixed the solution with a popsicle stick until it reached a thick consistency, then inserted my index and middle fingers until the mold solidified.

Once the negative mold was set, I used Rockite at a ratio of 70g of Rockite to 20g of water for each casting. I poured the mixture into the alginate mold and inserted two screws—heads facing down—into a 3D-printed hanger positioned over the container to allow the fingers to hang while setting. I let the mold sit for about 12 hours before removing the casted fingers. I repeated this process a second time using the same mold and the same Rockite ratio.

For post-processing, I used a wood file to shave off any excess Rockite and refine the edges for a more uniform appearance. Some alginate residue remained on the cast, which I also carefully removed. Once smoothed and to my liking, I spray-painted the fingers with metallic silver and finished with a clear protective coat.

Overall, this was a simple and effective process for molding objects. I learned that, because alginate is water-based, it’s important to remove the cast relatively soon after curing to prevent the mold from shrinking or tearing—especially along thinner areas. Despite its fragility over time, the molding process was fun, and I really enjoyed learning how to mold and cast using alginate!

Cost Analysis 

Material	Unit Price	Cost
Alginate	$11.99/24 ounces	$3.37
Rockite	$0.18 / Ounces	$0.44
Silver Spray Paint		$5.98
Clear Spray Paint		$6.19
Labor		12.75
Total Cost		28.73

 

Clean Workspace