Oh, and did I mention that it's made out of almost entirely upcycled materials? Two Altoid (or similar) tins and scraps from an old sweater make up the base structure and the eraser pad. A little glue to hold things together, paint to make it look pretty, and voilà! I used orange spray paint that I had leftover from a previous project and a simple hand-lettered title for my design, but (naturally) you can make yours with whatever design you like.
Step 1: Materials
2 Altoid tins
part of an old sweater (you'll need about 4X10" rectangle)
2 part epoxy or another glue suitable for gluing metal to metal and fiber to metal.
a few inches of wire or twine
Steel wool, or a wire brush
needle & thread
You could really make any size/shape of eraser using this scheme, but an Altoid tin fits spare chalk perfectly. Whatever shape you choose, you'll need to get two tins that are exactly the same size. An old felted sweater (or other knitwear) makes a perfect eraser pad. The type of fiber doesn't matter too much, anything thick and knit will do the trick.
Step 2: Make Eraser Bed
Use pliers to pry open the hinges of the tin. Detach the top from the bottom. Repeat with the other tin.
Use steel wool or sandpaper to remove the paint from both the lid tins. Though you need the tops from both of the tins, you'll only be using the bottom of one of them. Remove the paint from one of the tin bases. (You can discard the other.)
Glue lids together
Use 2 part epoxy to glue the tops of the two lids together. Arrange them so they are neatly stacked with the hinge sides aligned. (See picture)
If you want to paint the base (which will be the front of the eraser) you can paint it now. Avoid painting where the lid will hit-- this paint will just rub off anyhow.
Step 3: Sew Eraser Pad
First: it is crucial that you cut strips from your sweater with the correct alignment. If you get it right, the pad will wear beautifully, even if the sweater starts to unravel, the loft of the eraser pad will just get a little fluffier. If you get it wrong, then you'll get little flecks of yarn falling off as you use the eraser. (See picture for the correct alignment) You want to cut about ten 1"x 4" strips of the sweater.
Fold and Sew Strips Together
Fold one strip in half, vertically. Use a hand sewing needle and sturdy thread, sew a simple seam lengthwise through the center of the folded strip. Take another strip, fold it in half and align it so that the raw edges are facing the same direction as the first strip. Sew the second strip onto the first. Keep adding more strips, sewing each onto the previous row. Keep going until your pad is wide enough to fill the tin lid. You'll want it to be a little bit wider-- it's nice if the pad needs to be compressed a little so that it fits snugly into the lid.
Step 4: Finish edge of eraser bed
Cut a strip of paper so that it will exactly cover the space between the rolled edge of the two lids. Cut little notches to align with the hinge holes.
Glue trim to lid
Spread 2 part epoxy over the area that you'll be covering with the paper trim. Glue paper trim to the lids. (It seems a little flimsy, I realize, but the paper is just to give you a flat, even surface, the epoxy is what creates the structure.) Leave the epoxy to set up.
Once the epoxy has set you can paint the paper border however you like.
Cut a piece of electrical wire or twine to make into a hanger. Thread the wire through two of the hinge holes and secure each end with a knot.
Step 5: Finish
Mix 2 part epoxy and spread it over the surface of the inside of the lid on the side that the hangar is attached. Fit the eraser pad into the lid and place a heavy book on the pad to compress the whole assembly while the epoxy is setting up.
Attach lid to base
Once the the epoxy has set up, you can reattach the hinges, connecting the base to the top. Trim any scruffy edges off the eraser pad.
Paint design on base
If you like, you can paint whatever design you like on the base of the tin. This design will be displayed when you hang the eraser on the wall.
Cut felt lining for base
It's totally optional, but I cut a piece of felt to fit inside the base right beneath the chalk. This cuts down on the chalk movement when you're using the eraser.