Wedges & Splitting

Watch this for a second. An axe blade — it's not magic, just a thin slice of steel. But you swing it at a log and… CRACK. The whole thing splits in two. How does a flat piece of metal do that?

Here's the secret. You already know what an inclined plane is — it's a ramp. Now flip that ramp on its side, and instead of letting a block slide up it… make the ramp itself move forward. That's a wedge. The slanted face pushes whatever's in front of it out of the way.

Every wedge has two knobs you can turn. How LONG it is, and how THICK it is at the back. Mechanical advantage equals length divided by thickness. Long and thin gives you a huge MA — like a katana — but it's fragile. Short and fat gives less MA but takes a beating, like a splitting maul.

Once you know what to look for, wedges show up everywhere. Your kitchen knife. A doorstop. A chisel. The tines of a fork. A shovel. Zipper teeth. Even shark teeth — tiny serrated wedges. Once you spot one, you cannot stop seeing them.

Now build your own wedge. Pick how long, how thick, how hard you swing — and what you're splitting. Soft wood is easy. Stone is not. Then hit STRIKE. Try a thin one first. Then a thick one. Same force — different result.

Wedges aren't just woodshop tools. A scalpel is an extreme wedge — super long, super thin. A plow is a wedge that splits soil. A ship's hull is a giant wedge splitting the ocean as it moves. And the Egyptians used wooden wedges, soaked them in water until they swelled, to crack stone blocks for the pyramids.

So that's the whole story. A wedge isn't really about sharpness — it's an inclined plane that you push forward. The slope trades your forward distance for sideways force. Same exact trick whether you're splitting a log, slicing a tomato, or sailing a ship. An inclined plane on the move.