Things You'll Need
Silicone rubber kit
Acrylic resin kit
Acrylic resin is a type of plastic you can use at home to make a variety of shapes. This plastic is strong, non-toxic and largely inert, which makes it safe and appealing for many craft projects. Resin requires a mold, as it is a liquid prior to curing. You can buy or make your own resin mold from silicone rubber. Molds are suitable for complex shapes as well as very simple ones, such as a plain cylinder.
Mix some silicone rubber with its catalyst, according to the instructions, using a disposable plastic cup with a craft stick. Both rubber and catalyst are included in the kit. Pour a thin layer into the bottom of your box.
Place a cylindrical object the exact size and shape you want for your acrylic cylinder into the box, on top of the silicone rubber. Pour more silicone rubber around the cylinder until you reach the top. Do not cover the top of the cylinder or pour past the lip of the box. Wait for the rubber to cure. Curing times vary by brand.
Remove the box and the cylinder. If you have trouble removing the cylinder, carefully make a single slice with a sharp knife down the mold until you can pull out the cylinder. You must hold the mold in place with rubber bands, or a similar item, around the slice to discourage leaking.
Spray the inside of the mold with mold release. This makes it easier to pull out the acrylic part later and preserve your mold.
Mix the resin according to the instructions. Typically, you need to mix equal parts resin and hardener, both included in a kit. Mix thoroughly, scraping the sides of the cup, but not too vigorously, as it may add bubbles. Do not mix more than you can pour easily, and use in a couple of minutes.
Pour the resin into the mold. Tap the mold to encourage bubbles to rise to the top. If you are making a large cylinder, you may want to pour in stages, filling the mold partway, waiting for it to partially cure, then adding more. This is because resin becomes very hot as it cures, and a lot of resin curing all at once can melt the mold.
Wait for at least a full day before removing the cylinder from the mold. Again, if you have trouble removing the cylinder, you can slit open the mold without making it unusable for making another cylinder. Use a craft knife to scrape off any excess or unwanted resin that may have leaked through a slit in the mold.
Work in a well-ventilated area and protect your worksurface with newspaper or a dropcloth. Never touch uncured resin. It is safe once cured, but can damage your skin in its liquid form.