Once you've cut up your cardboard to size you'll often want to join it together. Here are some ways to do just that!
Hot Melt Glue
Hot melt glue is one of the best ways to join cardboard. It is fast to cure, strong, and can fill in gaps in uneven surfaces.
PVA White Glue
White glue works very well on cardboard. It's a bit slower to dry than hot melt glue, but requires no special tools, and is cheap and ubiquitous.
Brass Paper Fasteners
Punch a couple of holes in your cardboard, push a paper fastener through, and fold out the legs. Instant connection!
Rivets
Rivets make for excellent fasteners, and since they have a smooth shaft, they can be used for rotating pivot points and joints.
Screws
Makedo Scrus are specialized screws designed specifically for joining cardboard. They come in two lengths -- the short ones work great for two or three layers of cardboard, the long one can handle even more, particularly the thick, 5-ply cardboard from heavy-duty shipping boxes.
Zip Ties
Zip ties are incredibly versatile. Here's a trick for using them to create rivets of greatly varying lengths. Push one zip tie through the cardboard to be joined, then slip a second zip tie onto it. Trim the excess length.
Lap Joints
Looking for a nice, clean 90° joint between cardboard sections? Here's a great way to do that -- it's similar to a lap joint in woodworking.
- On one piece of cardboard, measure in from the edge the same distance as the thickness of the piece to be joined
- Trim away one face layer and the corrugation flutes from this section, making sure to leave the outer face intact
- Glue and fit the two pieces together, holding them in place as the glue cures
- Admire the perfect edge!
Support
Depending on your project, you may need a bit of extra strength and support where your walls are joined. There's a simple, yet effective way: cut a few triangular support braces and glue them into place!
