Introducing another cool thermoplastic, Sintra! It’s a foamed styrene plastic sheet that comes in a variety of thicknesses. It’s traditionally used for commercial signs, but costumers have discovered that it’s also great for making props and armour!
Volpin Props created this gun and used Sintra for the curved purple plates.
How to use Sintra
Like other thermoplastics, we recommend making a mockup out of cardboard or craft foam.
Sintra can be beveled or layered, and with heat it can be stretched or bent. It becomes flexible at 200-275 F and is best heated in boiling water or in an oven; a heat gun can be used for spot heating of certain areas. When heated, like many plastics, Sintra gives off toxic fumes – so please make sure you use adequate ventilation and don’t boil it in a pot that will be used for food.
For cutting Sintra, you need to use a sharp knife or box cutter, or a saw. To use a knife, score your cutting lines, and then bend gently to crease the back side; then turn over and score the other side carefully. You can then carefully snap along your scoring lines. The hard plastic coating can shatter if you don’t score the cutting lines adequately, or if you use a shearing cutter like scissors.
Sintra pieces can be fused using superglue, and smoothed with sandpaper. You can also use additional sculpting materials such as epoxy putty or Bondo to add details and further smooth angles.
IceTyrant’s Sintra Iron Man helmet, covered in Milliput and sanded. Build info on RPF’s forums here.
To paint, use plastic paints such as Krylon Fusion.
FOA Cosplay made this amazing World of Warcraft Paladin with Sintra.
How does it compare to other thermoplastics?
Sintra is thicker than the other thermoplastics we offer, so it can be great for quick buildup of dimension, and like our other styrene sheets, it has a smooth surface that doesn’t need much finishing. It is best for flat layering, beveled angling or for gentle curves; it doesn’t handle complex or compound curves as well as Worbla or Wonderflex and can wrinkle if bent/stretched excessively when heated.
Sintra cannot be vacuuformed; for vacuuforming we recommend the flat/solid styrene.
Here are some great tutorials to get you inspired!