Today I was trying to bend a leaf spring into a U-ish shape to secure a leg vise to a fence post I sunk in my shop's floor. I had gotten the first 90 degree bend and had put the piece back into the fire to make the second bend. I had to run up to the house so I turned off the blower and started to pull the piece out of the fire to set aside and it slipped from my grip. I immediately jumped 6 feet backwards before it had hit the ground, and when it hit it broke clean in half at the bend! I'm not sure if this is usual for leaf springs since this is the first one I've ever worked with, but what did I do wrong to make it crack like that? I may have quenced it after the first bend too, I don't exactly remember. Thanks.

It might be the quench, but it might also be the temperature you worked it at.

High carbon steels generally can only be worked between an orange and yellow heat. Too hot or not hot enough, and it's gonna break.

Secondly, recycled springs can also have tiny cracks in them. This is a long shot, but that might also be a reason.

Without having been there, I can't say for sure!

Thanks Mr Smith, it almost looked like a piece of cast or wrought iron that I had broken before. It looked almost granular. It's okay though because I decided to mount the leg-vise a different way.

Granular break usually indicates overheating at some point.

Thomas