The Broken Wheel Quilt Block harkens back to the days of the covered wagon. As you know, a flat tire can really ruin your day. Especially if it's raining. If you think a flat tire is a bummer now, just imagine what it was like back when the settlers were moving out west in the Mercedes Benz of the day. It wasn't like you could whip out your cell phone and phone a friend. Or call Triple A. Or have a tow truck take you to the local Firestone.
Whenever I see this block, I like to imagine that some pioneer woman named this block as she fondly remembered the roadside assistance her family received from another settler. I often wonder if quilt blocks back then were sort of like scrapbooks are for us today, with little bits of memories woven into the stitches.
At any rate, the Broken Wheel Quilt Block is a 9-patch block with Square-in-a-square units and 2-piece rail units revolving around a central square. Can you see the "broken wheel" (aka Flat Tire) in the center of the design? In each of the SNS units, the corner facing the center uses the same color as the central piece of the rail unit. This results in a circular hexagon type shape, mimicking a flat tire.
Below is a grouping of Broken Wheel Quilt Blocks, so you can see how the blocks interact when placed together.