Another way to shatter large boulders

[ragkar]

So you've managed to drag that boulder out of the ground or maybe it was too big for you and you only could dig a trench around it. What do you do now?
An old farmer told me this technique that he says he's used many times. I thought that I'd pass it along for your information.
First - wash the rock down to get all the soil off
Second - use brushwood to build a bonfire around the boulder. If it's in a pit then consider it a fire pit. Let the fire die down completely.
Third - throw ice cold water on the hot boulder. It will shatter into a thousand pieces.

BE CAREFUL - THIS IS A DANGEROUS PROCEDURE
The shattering boulder will throw pieces of rock and they could maim and hurt. The farmer says that he usually tried to hide behind something and use a long board with a piece of plywood nailed upon it as a tray to deliver the ice water container. I'm thinking that a pressure washer with a zero degree head may do the trick in a safer manner. But I would look around for one of those super-soaker water pistols that kids have these days. I understand that they can throw a stream forty or fifty feet.

If the boulder is in a fire pit then that would be a big help in protecting you from flying rock.

 

[MikeD74T]

From my experience I think you'll have a "thousand pieces" the size of your thumbnail & a very large piece left over. It takes both lots of heat & lots of water to break rocks, it's not a practical method. MikeD74T

 

[PA hayseed]

Interesting. I guess if you built a hot enough fire, it wouldn't matter how cold the water was. I've seen them split big rocks with the drilled hole, wood spike and water trick. Cracks em almost as if you had cut them with a saw.

When I was a kid we used to love throwing sandstone into a fire pit. Who am I kidding, I still do it when I am burning stuff.

 

[Farwell]

So you've managed to drag that boulder out of the ground or maybe it was too big for you and you only could dig a trench around it. What do you do now?
An old farmer told me this technique that he says he's used many times. I thought that I'd pass it along for your information.
First - wash the rock down to get all the soil off
Second - use brushwood to build a bonfire around the boulder. If it's in a pit then consider it a fire pit. Let the fire die down completely.
Third - throw ice cold water on the hot boulder. It will shatter into a thousand pieces.

BE CAREFUL - THIS IS A DANGEROUS PROCEDURE
The shattering boulder will throw pieces of rock and they could maim and hurt. The farmer says that he usually tried to hide behind something and use a long board with a piece of plywood nailed upon it as a tray to deliver the ice water container. I'm thinking that a pressure washer with a zero degree head may do the trick in a safer manner. But I would look around for one of those super-soaker water pistols that kids have these days. I understand that they can throw a stream forty or fifty feet.

If the boulder is in a fire pit then that would be a big help in protecting you from flying rock.

ragkar,
We split rocks using fire and water when I was a kid on the farm. We would dig a good sized pit under the rock and build a hard wood fire under it. The fire would burn for around 48 hours before we added water. Us kids would take turns keeping watch on the fire and feeding wood to it to keep it burning. It was an all day all night project but it worked. I don't remember any fragments flying all over the place.
The rock splitting was sort of like camping out, we always had a good time with hot dogs and roasted marshmallows.
The neighbor used dynamite, we felt that he was missing out on a good time.