rberger54
11-03-2006, 07:13 PM
I am new to this wonderful site & have been exploring some of the old threads. The Steel Carving discussions were real neat & I intend to try some. It brought back to mind a method I developed to work with Granite.
In the past I "carved" stone - Granite. My attraction to Granite is that it is pleantiful, and a real challenge. To anyone who does this - it is not traditional carving, but hammering, usually with an air hammer to mash up the granite to remove the material as sand or dust. The only abrasives that work are diamond tools.
I came across an idea of trying to apply the old mining technique of Thermal Shock. They burned a big fire over a rock outcrop for many hours, then removed the fire & poured water on the hot rock - and the rock broke up & spalled off from the thermal shock.
What I did was to run a Carbon Arc over an area of the granite - it immediately caused the formation of a glass fusion crust. In one second this could be broken off with the tip of a screw driver, exposing virgin Granite. Since the fusion crust would form immediately, the underlying Rock did not seem to overheat. My fear was that the heat or UV Radiation would alter some of the Granite composite cristals & minerals - feldspar, Quartz, mica or whatever changing the character of the Granite, but I never noticed that as a problem. I am sure some of the minerals melt and fuse first - it leaves a bit of a rough surface. The most I was able to remove in one fusion crusting was about 1/8 to 1/4 inch of Granite beaded up into the fusion crust. On one sculpture, I was able to sculpt a hole all the way thru about 4 to 5 inches of Granite. After about 1/2 hour of straight fusion crusting I would have to give it rest since the entire rock would begin to heat up.
One of my sculptures has been outside now for over 5 years with no apparent adverse weathering.
Just throwing it out there to other stone sculptors.
In the past I "carved" stone - Granite. My attraction to Granite is that it is pleantiful, and a real challenge. To anyone who does this - it is not traditional carving, but hammering, usually with an air hammer to mash up the granite to remove the material as sand or dust. The only abrasives that work are diamond tools.
I came across an idea of trying to apply the old mining technique of Thermal Shock. They burned a big fire over a rock outcrop for many hours, then removed the fire & poured water on the hot rock - and the rock broke up & spalled off from the thermal shock.
What I did was to run a Carbon Arc over an area of the granite - it immediately caused the formation of a glass fusion crust. In one second this could be broken off with the tip of a screw driver, exposing virgin Granite. Since the fusion crust would form immediately, the underlying Rock did not seem to overheat. My fear was that the heat or UV Radiation would alter some of the Granite composite cristals & minerals - feldspar, Quartz, mica or whatever changing the character of the Granite, but I never noticed that as a problem. I am sure some of the minerals melt and fuse first - it leaves a bit of a rough surface. The most I was able to remove in one fusion crusting was about 1/8 to 1/4 inch of Granite beaded up into the fusion crust. On one sculpture, I was able to sculpt a hole all the way thru about 4 to 5 inches of Granite. After about 1/2 hour of straight fusion crusting I would have to give it rest since the entire rock would begin to heat up.
One of my sculptures has been outside now for over 5 years with no apparent adverse weathering.
Just throwing it out there to other stone sculptors.