Processing guides
Edge
The edges of special pieces (countertops, window sills, steps, etc.) can be processed in several ways; this work can be done at the customer’s location or at the workshop, using hand tools or CNC machines.
Types of edge processing:
1. Bullnose / half-bullnose
Bullnosing is an edge-processing technique that gives the edge a fully rounded (convex) final look. When only half the edge is processed this way, it’s called “half-bullnose.”
Besides its aesthetic value, this processing also makes the finished product easier to maintain.
Bullnosing is done by hand, with specific tools and equipment, or automatically, using CNC machines.
When done by hand, the process follows these steps:
the customer sets the processing dimensions
measurements are taken and marked
the piece to be processed is secured to the workbench
work starts on the first edge
a first (rough) grinding pass is done on the edge with an angle grinder fitted with an abrasive disc. The disc type, with the abrasiveness needed, is chosen based on the stone’s hardness (granite, marble, travertine, limestone).
a second (finer) pass is done on the edge, using a less abrasive disc.
finishing is done with sandpaper of several grits, working in stages from the coarsest (under 1000) to the finest (1500-2000). Alternatively, a softer wire brush can be used, followed by fine-grit sandpaper. During this, the edge is frequently cleaned with a wet sponge, to prevent residue from building up on the surface.
polishing with specific discs or brushes
the same steps are repeated for the second edge
once polished, the whole piece is sealed
For CNC processing, tools that mill both the top and bottom edge simultaneously in a single pass are used.
2. Chamfer / double chamfer
Chamfering is an edge-processing technique. In practice, it involves cutting the edge at a given angle, usually 45 degrees. Besides its aesthetic value, this processing also makes the finished product easier to maintain. When done on both edges, it’s called a double chamfer.
Chamfering is done by hand, with specific tools and equipment (a jigsaw with an adjustable base, a circular saw, a grinder with a 45-degree milling attachment), using water-jet cutting machines, or automatically, with CNC machines.
The process follows these steps:
the customer sets the processing dimensions
measurements are taken and marked
the piece to be processed is secured to the workbench.
a first cutting pass is done using a circular saw or a jigsaw blade. Using a water-cutting machine with a fixed frame for blade movement has the advantage of rigidity, reducing vibration and the risk of blade warping.
a second (finer) pass is done on the edge, using a grinding disc.
finishing is done with fine-grit sandpaper
Once chamfering is done, the whole piece is sealed.
3. Chamfer with polished edge on one side
Chamfering is an edge-processing technique done by cutting at an angle. It’s done by hand or by machine. After cutting, the edge length remains rough, unfinished. It’s polished using an angle grinder or sandpaper.
