How to Make Plastic Moldings

by HomeRepairExpert.com
You can make your own plastic molds at home in any shape that you choose. This allows you to make your own custom designs for art projects, house decorations or even for a science project. Create a custom plastic mold to make a statue, a model of planets or anything else that comes to mind.

  • 5-gallon plastic trash can with 8-by-12 inch rectangular top
  • 8-by-12 inch metal baking pan
  • Two 8-by-10 inch picture frames
  • 12-by-12 inch plastic sheets
  • 10 wooden clothespins
  • Silicone caulk
  • Vacuum with attachments
  • Drill
  • Craft knife
  • Blow dryer
Place the baking pan upside down on a work surface. Use one hand to hold the baking pan steady while your free hand uses the drill. Drill holes in a grid pattern, all equally apart. Each hole should be approximately 1/2 inch apart. Create rows, making your way down the pan, making sure there is also 1/2 inch between each row. If it's easier, use a ruler and marker to create a grid pattern before you start drilling.

Cut a hole in one side of the trashcan to allow insertion of a vacuum attachment piece. When choosing an attachment piece, find one that fits onto your vacuum but that you also do not mind permanently attaching to the suction console. Use a marker to trace the shape of the end of the vacuum attachment that you vacuum with onto one of the sides of the trashcan about 3 inches from the ground. Cut the shape you have traced out of the trashcan using an craft knife. Do not cut larger than what the trace marks show. It is better to have the hole too small than too big.

Turn the trashcan upside down inside of the baking pan. Use silicone caulk to attach the top of the trashcan's edges to the inside of the baking pan to create an airtight seal. Leave the trashcan upside down until the caulking fully dries in about 8 to 10 hours.

Insert the side of the vacuum attachment that you vacuum with, approximately 2 inches inside of the trashcan. This will leave the end of the attachment that the vacuum hooks up to outside of the trashcan. Just as you did with the baking pan, use silicon caulking to caulk the edges of the vacuum attachment, creating an airtight seal. Allow all caulking at least 8 to 10 hours to fully dry before your suction console is complete.

Remove the backing from both picture frames as well as the glass. Set one frame face down and place a 12-by-12 inch plastic sheet on top of the back of the frame. Place the backside of the other frame on top of the plastic so that both frames' backs are touching with a plastic sheet in between them.

Clamp the two picture frames together using 10 wooden clothesline pins. On the two short sides of the frame, use two pins on each side equally apart. On the two long sides of the frame, use three pins on each side equally apart. Clamp the frames around the plastic, allowing no slack.

Prepare the object you're going to mold. For example's sake, we'll make a mold out of a toy car. Make sure the toy car is clean and completely dry. Place the toy car right side up in the middle of the suction console, which is the top of the baking pan.

Hold the side of the frames with one hand, and with the other use a blow dryer to heat up the plastic sheet. Set the blow dryer on the highest heat and hold it 3 to 6 inches away from the plastic. This will heat up the plastic, slowly turning it from clear to white. Once the plastic starts turning white, it will soon start melting and loosening up in the middle. When the middle of the plastic starts to sag, the heating process is finished.

Holding each side of the picture frame, gently place the plastic over the toy car. Make sure the toy car is in the middle of the plastic, within the frames. Push the frames down to lay on the surface of the baking pan.

Attach the vacuum to the vacuum attachment connected to the trashcan immediately after you have placed the heated plastic over the toy car. While the plastic is still hot, flip the vacuum on and then off immediately after. This will suction the plastic to the car, creating the exact shape of the car. Most likely, the first flip of the vacuum switch will complete the seal between the plastic and the car. If it hasn't, simply repeat this step one to two more times as needed. Let everything sit for 30 minutes to the let the plastic cool off and harden.

Slide the car out once the plastic has cooled off. With scissors, cut the excess plastic surrounding the mold of the car.



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