Before You Begin

There are many types of props that could be made via foam carving. Before you begin, you must consider exactly what it is you will be making, and what type of foam will be best for the job. This is of primary concern for prop weapons, which will often be swung around, or used to hit/poke things. If you use a foam that is too delicate, a prop weapon will break after coming into contact with something else. E.g.: being dropped on the floor, poking someone, poking another inanimate object. Note: even if it's not intended, props can and will be dropped on the floor.

Also, be sure to choose a foam of similar/appropriate shape/size for the prop to be made. 

Types Of Foam

• Styrofoam is a thick white foam. It is often one of the best choices for prop weapons. Unless you can guarantee that the weapon will not touch anything else (remember, Directors and actors love to change things --and not tell you–) it is the safest choice. Styrofoam is nice and sturdy, although it is more difficult to carve. 

• Floral Foam is a green, granular foam. This is best for making props that are more stationary, especially if they have a more amorphous shape. Ex: a meatloaf.

  • This has very tiny granules that can be breathed in, so make sure to use a facial mask when carving. 

  •  This foam is bad for weapons. It cannot withstand impact with the ground or other objects

    •  More importantly, the very small granules make it nigh impossible to glue things to this foam. The top layer of grains will slough off. 
      •  Even if pieces are not glued together, the paint will detach the top granule layer and actually rip from the foam.
      •  Pls do not use this for weapons unless it's the only option. This is a very difficult problem to fix.
• Balsa Foam(?)--currently unsure if this is the correct name. This is a pretty lightweight foam that is not granular at all (not even like styrofoam) and is very smooth.
  • This foam by itself is sub-optimal for weapons.
    • Weapons purely of this foam tend to  break after being used to poke something, or being dropped. The foam itself is what breaks, because it is too lightweight.
      • However, this can be fixed by using balsa wood or cardboard as a stabilizing backing.

Prop Creation

Carving

Materials: sharpie, ruler, compass (or a tac and string), exacto knife, hefty exacto knife, trash can, glasses/goggles (optional), face mask (optional unless you're using floral foam). 

Note: You will be covered in foam powder. Covered in it. Hence the trashcan.

• Use the ruler for any straight lines in the prop. Pls. 
• use the compass/string and tac for any curves.
  • You can ground the compass in the middle, or shift the grounding point (even while drawing a curve) for differently arced curves.
• After carving (Ex: the edge of an axe), you must smooth out new edges afterwards by running the blade of a knife along the new straight edge to make foam grains slough off.
  • esp. for styrofoam
• If you feel like you cannot draw enough to over-determine the new shape of the prop:
  • see the prop
  • carve the prop
    • Yeah sorry that's about it. gl hf. 

Finishing

Styrofoam

• Paper mache should be used to attach paper (ex:newspaper, any paper really) to all sides of the prop. This creates a flat surface for painting, which makes the prop look nicer and more finished.
  • Make sure to press paper flush to the prop
  • Paper mache can be substituted. 
  • You can also choose not to make the foam flat, e.g. if you wanted to make a more shiny reflecty and rough surface.
• After using paper mache and allowing it to dry (wet side up) you can paint the prop.

Floral Foam

• Spray foam with a foam sealer, or a white base coat of paint meant for foam. Make sure to completely cover the foam with multiple coats.
• Afterwards paint with multiple coats of normal paint.
  • Note: as mentioned above, there is a danger of the paint coming lose and tearing from the prop. Prop will be delicate. Try not to drop. 
    • Avoid using this foam for weapons. Plis.

Lightweight/Balsa(?) Foam

• Trace the prop out on cardboard, foam board, balsa wood, or some similar material.
• Cut out traced shape, and attach this to the foam with the appropriate adhesive. (Hot glue is fine–feel free to use foam glue, but for the love of god don't even think of using a glue stick).
  • This backing should add structural stability and prevent prop breakage. Good for front and back of prop. 
• Paint.