Introduction: Cardboard Book Shelves, Like a Carpenter
If you are looking for a fun carpentry/woodworking project but lack the facilities or initiative to accumulate the tools and skills, this project will give you the same feeling of satisfaction at a job well done. I have taken the time to create CAD drawings to spell out how to make a cardboard alignment square, how to lay out the parts, even how to get great results folding. Please provide lots of suggestions for the next one - I have built many pieces but have 000 practice teaching other people. I am trying to cater these instructables to novices and clever engineers alike. Keeping this in mind, feel free to let me know if I have left out key information or if I am talking to you like you are "5". Hope you enjoy!
This page shows you how to make a cardboard alignment square. Alignment squares save you alot of time by isolating the position of parts down to one axis - thats just one measurement per shelf support, also known as a ledger. Just lay out a single hatch mark where you want each shelf. Hold the square against the edge of your side (known as an "upright" to cabinetmakers) and glue down the ledger...no more measuring and checking for square. Notice that the ledgers end 1/8" away from the edge. That is the thickness of a sheet of corrugated. Check the photos and drawing for more explanation.
Cut ledgers from your 1 7/8" stock. They should be 1/4" shorter than the width of you sides - in this case, 10 3/4". You'll need 8 of them.
When you glue the ledgers, It helps to apply a quick zig-zag of glue - it cools quickly.
At the end of this step you should have two identical sides, each with 4 ledgers glued to them.
Scoring cardboard for a fold can be challenging. It is thick enough to require some force to cut through, but thin enough that you might accidentally cut too much. I've worked with foam-core and cardboard both, and have figured out two methods which are sort of ok, and one which is dead-on.
First method - just ok
Draw one center line OR two parallel lines 1/8" apart. Note in the drawing how you can make a marking guage to draw these lines. Cut a v-groove freehand. fold.
Second method - wow!
Dig a 1/8" wide trough 75% down. This removes enough material to provide a relief for the fold. I find these folds are stronger and less likely to spring open compared with a v-groove.
Second method #2 wow wow.
I am spoiled and actually use a table saw for cutting and scoring. Flimsy material like cardboard is more likely to flex the wrong way and kick back, so you have to be very aware...but definitely scoring and cutting with a table saw is the way to go, fast fast fast.
After you have scored for a fold, press it past 90 degrees a couple times to work in a nice fold. Then glue to its corresponding ledger. Note the the bottom shelf has a face which is 1" wider than the other shelves. And the top shelf is 1/8" deeper than the 2nd and 3rd because it will sit "on top" of the back.
When you are ready to glue the shelves in, squirt a thick bead of glue into the crevice between the ledger and the side. Get a friend to hold it in place as you clamp it with a length of tape, as shown in the last image.