The Ikea Billy, a freestanding bookcase, comes in white, brown, black and birch veneer and in two standard heights. The top, bottom, sides and shelves are constructed of particleboard covered with wood veneer or plastic. The shelves are designed to fit the bookshelf, but because they are made from particleboard, it's possible to cut them if you need adapt them for another purpose. You can do this with a circular saw, table saw or jigsaw, but you need to use a special blade and cutting procedure if you want to avoid chipping the veneer or plastic coating.
Equip your circular saw with a carbide-tipped blade that has 80 or more teeth to make a crosscut or rip cut. You can also make these cuts with a table saw after first installing a similar blade. To make curved cuts, use a jigsaw with a metal-cutting blade.
Mark the cut line on the back of the shelf -- the side that will be least visible -- when cutting with a circular saw. Cut from that side of the shelf. When cutting with a table saw, push the shelf through with its best side facing up. These strategies minimize chipping on the good side of the shelf.
Support the shelf on a workbench with the off-cut hanging over the edge to cut it with a circular saw. Hold it firmly -- clamping it to the bench, if necessary. Set the cutting depth of the saw to 1/4 inch and make a preliminary cut. When this is complete, set the depth to cut all the way through and make a second cut. When you're finished, bot sides of the shelf should be chip-free.
Employ a similar technique when cutting with a table saw. Set the blade height to 1/4 inch and make the first pass, then set the blade height to about 1/2 inch more than the thickness of the shelf and make the second cut.
Minimize chipping when cutting curves by laying masking tape on the shelf and drawing the cut line on the tape with a pencil. Cut through the tape with a jigsaw. Don't turn the shelf over and cut from the back when cutting curves; that makes taking measurements and drawing lines more difficult.