This Instructable covers the process of creating a wax model ray gun, then making a plaster mold from that model and then slip casting a clay version of that model which then is fired to make salt and pepper ray guns. Before attempting this Instructable I would recommend joining a pottery club or a maker space that has a kiln or make friends with a potter to save yourself having to buy a kiln $$$.
Step 1: Materials
Jewelers carving wax, Clay, Pottery Plaster, Mold soap (murphys oil soap), Porcelain Slip Cone 6 ( the stuff doll makers use), Elastic bands, Container with a spout (laundry detergent container), Black Mason stain,
2 Chopsticks, 2 Wine bottle corks, 3/32” O.D. stainless steel tubing, wood block, electrical wire
Woodworking tools, Drill, Exacto knife, Files, sandpaper, lego, Clamps, Craft brushes, High fire Kiln, Paint mixer, Sharpie marker, Kitchen scale, Mixing bowl, Spatula, Gloves, Loop tool, Dustmask, and Drill bit 3/32”.
Step 2: Create Model
To accommodate for shrinkage of clay start with 13% larger scale drawing of model of what you want the shakers to look like. The model can be made from various materials like Polymer Clay, or plastacine, or wood. I use hard jewelers wax because its quick to shape and you can achieve fine detail and crisp edges. Start by cutting the silhouette out with a scroll saw or band saw then refine shape with files then smooth with dry wall sandpaper. The wax can also be shaped on a lathe or with a drill like in the attached video. Wax elements can then be glue together with krazy glue or heated with a soldering iron and melted together.
Step 3: Mold Frame
Using Lego create a frame around the wax model leaving an inch space around it. Then roll out a inch thick slab of clay and trim it to the size of inside the lego frame. With a sharpie marker draw a line on the half-way mark around the wax model. Then push the model into the clay up to that halfway mark. Then place the lego frame down around the clay. Lightly press the clay to the edges of the frame and the model.
Step 4: Mix Plaster
Place a mixing bowl on a kitchen scale add 2 cups of water zero the scale then add 1 lbs. 7oz (646.5g) of plaster . Slowly mix together with spatula then wearing gloves run your hands though the mix looking for any lumps. Slowly pour the plaster mix into the frame careful not to pour directly onto the wax model. Gently tap the frame to allow bubbles to rise to the surface. Allow plaster to sit for an hour before removing from frame.
Step 5: Second Mold Half
Flip mold over and remove clay . With a small coin carve four circular divits into the plaster, these will act as registration so that the two halves of the mold will line up. Careful not to create any bubbles paint 2 thin coats of mold soap on the plaster this will keep the two halves from fusing together. Allow the soap to dry between each coat. Mold soap can be made from 50-50 blend of murphy’s oil and water. Place plaster with model back in lego frame and then repeat step 4.
Step 6: Finish Mold
Carefully separate mold halves and remove wax model. With a loop tool trim the sharp corners and round the edges on the outside of the mold halves. From the tip of the gun shape carve a funnel to the outside of the mold. Pay close attention to the point where the funnel connects to shape ensure that it is circular because this will determine the shape of the opening in the casting. Wrap two elastic bands around the mold halves to hold them together.
Step 7: Pour Slip
Using a drill and a paint mixer mix the slip for at least three minutes . Add slip to a container with a spout (empty liquid laundry detergent containers work well because the spout can be removed for mixing). Tilt the mold so that the funnel is upright. Slowly pour the slip into the mold while tilting the mold side to side to ensure that there are no trapped air bubbles, Fill until funnel is full.
Step 8: De-mold
Allow slip to stay in mold for 15 minutes. Slowly pour liquid core back into container, tilt from side to side to ensure drainage from all compartments. Set mold on top of chopsticks funnel side down and let dry for at least 45 minutes. Carefully remove elastic, separate mold, and gently remove casting. Then using a knife trim off funnel and clean up mold lines.
Step 9: Coloring
The Salt shaker can now be left to dry. There are many options for coloring the pepper shaker I will detail how to color the pepper shaker with colored slip so that it will only need to be fired once in the kiln. Make some “L” stands out of left over clay from the removed funnels. Pour a 1 cup of slip into a container with lid. Wearing a dust mask mix in 1 teaspoon of black mason stain powder. Using a soft brush stroke on colored slip carefull not to put any slip onto the opening. Rest the pieces on the pre made “L” stands.
Step 10: Firing
Allow pieces to dry for a couple of days or until they are no longer cool to the touch. Load the pieces into the kiln make sure they are not touching one another or the walls of the kiln. Fire at the pre programed Cone 6 firing (always fire your kiln in a well ventilated area and away from anything combustible). Once the kiln has returned to room temperature you can unload your shakers.
Step 11: Stoppers
Using a belt sander or a coarse file shape some wine bottle corks down until they fit in the ends of the shakers then using a knife cut them to an appropriate length. With a drill and drill bit drill 3 holes in the cork length wise. Then insert stainless steel tubing and cut to the correct length with a hack saw, file and sand off the sharp edges.
Step 12: Display
Cut a wood block (2x4) 6 inches long , sand it , stain it , drill two holes ,and stick black electrical wire in one and white in the other. Bend the wires into a “Y” shape that fits the grooves on the shakers. Now fill with salt and pepper and you ready to season your food in style.
Thanks for Looking and if you like it please give it a vote on the Casting Contest!
First Prize in the