m50_SS_Cardboard-5

Cardboard can be found all around you. You can rip it, bend it, cut it, or even shape it with a laser cutter. Using a projector, you can transfer papercraft designs onto cardboard to scale-up fun slot-and-tab projects.

Board Types
When we talk about cardboard, most of the time we’re actually referring to common corrugated C-flute fiberboard. This is the 4mm thick, slightly squishy stuff most cardboard boxes are made from. It consists of two layers of rough, fibrous paper, with one inner fluted layer. There are varying sizes of fluting with thicknesses ranging from around 12mm triple ply to 1.8mm E Flute. The corrugation provides rigidity and bears weight when oriented vertically.

Cutting Cardboard
Lasers, water jets, die cuts, jig saws, utility knives, and tough scissors all cut cardboard. Score with a penknife and crease with a bone folder. A tri-edge architectural ruler also makes a handy tool for creasing. A rotary tool can carve fancy curves quickly, if you don’t mind noise, dust, and fuzzy edges.

Shaping
Creasing along the grain can produce curvature, while working against the grain requires a hard crease or a score, so that the corrugate does not break the line. Fold into the cut, so that there are no exposed layers of corrugation. Wet cardboard can be molded into subtle shapes using a damp cloth and dried in sunlight.

Hardware
Handheld staplers from Bostitch and Rapid 31 with “sword-points” can be used for hard-to-reach joinery. Mr. McGroovy’s Box Rivets are snappy joinery for articulated points or easy tear down. Enlarged slot and tab systems used by paper crafting and nomadic furniture designers are desirable for intuitive assembly and disassembly.

Making it Last
For durability, avoid tape if you can — especially duct tape. Masking tape can be employed for sealing gaps without compromising strength. A cooked starch-based papier-mâché (see recipe, below) can add strength and use up your extra scraps. If you want to waterproof, seal with shellac.

—Cardboard Teck Instantute

Perfect Cardboard Papier-Mâché Recipe

This recipe was originally introduced to me by Vermont’s Bread & Puppet Theater. It has served me well.

Dissolve 1 cup of cornstarch in 2 cups of cold water, then slowly mix it into a half-gallon of boiling water. Turn off the heat and stir periodically while it cools, about 45 minutes. Keep stirring until you can see the glue adhere between the tines of a fork and the appearance is consistently cloudy and milky.

Rip scraps of cardboard and drop in water until the layers separate. Wring out scraps until the paper feels leathery and wrinkled.

Apply the paste liberally with your hands to the scrap and wipe surfaces free of all glue, pushing firmly on the edges to adhere the fibers.

—Ben T. Matchstick