Posted on

Tool Guide: Focus on Stone Shaping

People have been shaping stones for millennia. As a natural material, stone varies widely, and a range of methods and tools can be used to achieve a similarly wide range of purposes. Stone shaping, focuses on basic techniques that are appropriate for landscape uses and building structural walls with stone. These techniques can often be applied to other types of stonework, such as veneer, as well.

“Stones are strong in compression, but weak in tension,” writes Brian Post, DSWA Master Craftsman, in this very informative article on stone shaping which appeared in this updated March 3, 2023 article (originally published in October 31, 2019 ) of Mother Earth News magazine. In the Basic Techniques for Shaping Stone article, Brian starts by explaining the difference between level bedded and irregular stone. He then details the tools and techniques used for various types of shaping: splitting, high spot removal, dressing, bending, tracing a line, etc. using different hammers and chisels. You can read the full 6-page article here.

Splitting:

Done by applying a force through a wedge tipped hammer or chisel. The stone immediately against the sides of the tip of the chisel is in compression, the rest of the stone will be in tension, where it is naturally weak, and this will allow the stone to split. Splitting is best applied in the direction of the bedding plane or with the grain of the stone.

Tools to use: Stone Busters, Tracing Chisel, Trimming Hammer

How a stone is supported has a tremendous effect on how it breaks.

High Spot Removal:

A critical part of getting stones to fit together when stacked, but it can be difficult because hitting a bump on a stone directly puts it in compression where it is quite strong. Using a point, concentrates the force causing chips to break off. Getting the correct angle and using a directional point makes it possible to split off larger pieces.

Tools to use: Directional Point, Point, Mason Chipper, Stone Busters

Dressing:

Generally refers to final shaping, done with lighter taps, to square up stones or put decorative textures on the stone. Often the light taps are essentially wearing away or slightly crushing the surface of the stone in a controlled way.

Tools to use: Directional Point, Point, Mason Chipper, Tracing Chisel, Mason Chipper

UPCOMING STONE SHAPING WORKSHOPS:

Register for an upcoming Stone Shaping workshops for the year! In these workshop you’ll be introduced to a variety of stone types, and how to work with them. Both hand and power tools are demonstrated and used.

To see stone shaping in action, check out the How To videos on the Stone Trust website. All the tools used for these demonstrations can be found in the Stone Trust online store. Below (and to the right) are examples of stone shaping videos.

UNDERSTANDING  –Dressing granite, trimming off drill marks and more:
Watch Brian use a variety of tools are used to quickly remove quarry marks, soften drill holes, soften sharp edges, and remove drill hole marks entirely.

UNDERSTANDING HOW TO USE: a Rebit PKM 25 Point to Shape Stone:
A demonstration on what can be done with its versatile directional point to effectively shape even very hard stones. This video shows what can be done on a very hard granite like stone.  The PKM25 chisel is being used in conjunction with the Trow and Holden Chisel Wizard and Hand Hammer.

UNDERSTANDING how Stone Busters can be used for all kinds of trimming and shaping on Vermont fieldstone:
A large part of shaping when working with fieldstone is done with Stone Buster hammers. They are versatile, powerful, and can be used with great accuracy as well with the important bonus of not having to worry about hitting your hand while using these hammers.