Foam-Core Prototyping
GETTING YOUR IDEAS OUT OF YOUR HEAD
AND INTO THE REAL WORLD.
Prototyping
 It is necessary to be able to convey your ideas to
others effectively.
 A picture is worth a 1000 words . . .
 . . ., but a three-dimensional prototype is most often
needed.
 A prototype:
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is inexpensive
is quickly made (in comparison to the final product)
represents the proposed product or device
Types of Prototypes
 There are several types of prototypes:
 Concept drawings (simple sketches to get the ball rolling)
 Virtual computer simulations (like Solid Edge)
 Mathematical models (MathCAD, MatLab and Excel)
 Clay models (often seen in the automotive industry)
 Foam-core (like the one you are about to make)
 Some prototypes are fully functional, …
 … but many are just spatial representations.
Foam-Core
 Foam-core (or Foam Board) is one material that can
be used for quickly prototyping your ideas.
 Foam-core is a composite material consisting of:
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An outer layer of card stock
And inner layer of foam (like Styrofoam)
And another layer of card stock
Tools for Working with Foam-Core
 Only a few basic tools are needed for Foam-Core:
 Cutting mat (so you don’t cut up the table top!)
 Cutting knife (Exacto, or box cutter) with a sharp blade
 Metal ruler (for measuring and making straight cuts)
 Pencil or a pen (for marking the cut lines)
 Tape (clear packing tape works well)
 Hot glue can be used also, but not required (low-temperature!)
Getting Started with Foam-Core
 Make sure you have a good, solid surface to work on
and BE SURE TO USE THE CUTTING MAT!
 Let’s start with just cutting a straight line
 Since foam-core has three layers, it is usually best to
make three cuts:
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Cut through the top layer of card stock
Cut through the layer of foam
Cut through the bottom layer of card stock
 If you try to cut through all three layers at once, you
will end up with a jagged mess!
Cutting a Line
 First, measure and mark the line.
 You may want to start at the 1” mark on your ruler, as the scale
on some rulers does not go all the way to the end.
 Be sure your fingers are out of the way!
 Make the THREE cuts.
Types of Corners
 At some point you are going to want to join your
foam-core pieces together – there are at least three
types of corners that you can make:
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Overlapped
Mitered
Rabbeted
Overlapped
Mitered
Rabbeted
Overlap Corner
 The overlap joint is the simplest corner to make.
 Simply cut the two pieces and tape them together to
create the corner.
 It helps to lay the tape down (sticky side up) on your
work surface and place the first piece of foam-core
on top of the tape.
Miter Corner
 Mitering a corner makes for a nice clean outside, as
there is no break in the material.
 Cut a V-shaped groove in the foam-core.
 The angle of the “V” determines the angle of the
resulting corner.
Rabbeted Corner
 The rabbeted corner gives a nicer looking corner
than the overlap, and is easier than making the
mitered corner.
 Cut through one layer of cardstock, and the foamcore, but not through the other layer of cardstock.
Only cut through two
layers of the foam-core.
Cut at 90-degrees from
your first cut to form the
rabbet.
A rabbet!