Hearthstone
Tuesday, September 11th, 2007
The stone we found for the hearth was a foot thick, roughly six feet in diameter and weighed 5,000 pounds. We decided to cut it down in size, to make it work with the firebox and the structural stone wall it will be built into. Ian began by drilling fourteen holes along the desired cut line. Each hole was five to six inches deep. He even drilled one into the end of the stone that he stuck up in the air.
The feathers and wedges were set in place, lined up carefully to ensure the force applied breaks the stone along the desired cut line.
There’s nothing quite as satisfying as when the stone begins to crack. The musical tone of the wedges changes as you strike them and then the rock itself starts to make a noise that sounds like it’s relaxing. The crack starts small, but usually travels quickly between the wedges.
Ian stands proudly over the finished cut. His foot rests on the bottom of the hearthstone. The left over piece will be used elsewhere, possibly split again for the uprights supporting the arch over the fireplace.
To learn more about cutting stone, visit the how to article in the Art & Craft section of our site.
Though it was considerably smaller, it was still a challenge to move the hearthstone. We loaded it up onto Urusla and drove it into the site. We outfitted the Bobcat with forks to actually set the stone. In this image you can see the treads lifting off the ground as the machine gained the needed leverage.
We brought the stone into position and set it down on a timber scrap to get our placement just right. Having the scaffolding out of the way helped us to visualize how the stone would look in the room and how it would feel walking through the front door. I mimed walking through the nonexistent door several times to get the sense of it.
We marked the footer with the shape and placement of the hearth and then backed the stone out with the Bobcat. We trimmed down a few foundation stones that might prove troublesome if the hearthstone rocked on them.
We laid our mortar bed and brought the stone back into position very, very carefully. Becuase of the way the Bobcat carried the stone on the forks, we set the back edge down and gently laid the stone down on the mortar bed. It ended up exactly where we wanted it. Good planning and Ian’s precision Bobcat operation made all the difference.
Because of the way we set the stone down, the front edge floated a bit high, preventing the stone from settling into level. It was a only a little bit off, but it was hard to correct. We tried a few options…
The Bobcat pushed down on the front edge of the stone and wiggled from side to side, but it didn’t budge the stone at all.
My favorite solution was synchronized jumping masons. Stone didn’t budge, but it was still a sight to see.
The best solution was to strike the front edge of the stone with a sledge hammer (cushioned by a scrap two-by-four) with the back edge counterweighted to prevent the stone from see-sawing. It only took a few minutes to get the stone leveled.
Throughout any major project, there are milestones along the way. Laying the first foundation stone was exciting, as was setting the first wall stone and placing the first window buck. Setting the hearthstone was satisfying, not just because of its immense size. Like with raising the batter boards, it gives the cabin shape and space.
The photos in this blog entry were taken by Ian Kelley and Todd Weatherly.
With the scaffolding down, we got our first look at the overall flow of the stonework. It’s important to step back to see the work. It’s hard to do though, when the wall is hidden behind a maze of metal framework and walk boards piled high with rock and tools.
Jesse and Scott work on a low section of the north wall. String blocks tagged to the batter boards guide our work.
Today we mounted the first two window bucks and began running the wall up between them. On days like this we spend a lot of time persuading stones to make right angles.
