Flatbed Glass Grinder

Properties & Qualities

Application

Art, Product, Other

Qualities

3D, Polished, Smooth

Colour

Other

Sample Information

Date of creation

28/08/2023

Culture & Context

Flatbed grinders, sometimes called lap or flat lap grinders, are used to remove material and create a flat surface on glass. They use a flat steel wheel combined with either a range of silicon carbide grits or magnetic discs. This example uses magnetic discs, which have a surface of electroplated or resin-bonded diamond in a range of grits. When using loose grit, workshops may have a separate machine for each grade of grit, or the machine must be cleaned very thoroughly between each one.

Process & Production

Flatbed grinders are always used with a water feed to keep the glass cool and prevent cracking caused by thermal shock. When using magnetic diamond pads, slightly more water will be needed for the rougher grits and less for the smoother.

Recipe Details

Start with a rougher grit such as 60, 80 or 100 to get the glass flat and remove more material. Rinse off between grits / discs and then move on to a finer grade. You can mark the area you are grinding using a permanent marker or wax (chinagraph) pencil, as an indication of when you have fully ground each grit. If you are grinding an edge, such as the rim of a vessel, it is recommended that you bevel the inner and outer edges of the rim between grits on the flatbed. You can do this using diamond pads or linnisher belts combined with water. Bevelling the rim will prevent the flatbed from chipping the glass at the edges. To ensure the piece remains level, rotate it by a quarter turn regularly as you grind it. You can also use tools such as a bubble level on top of the piece to ensure it stays level, or check it using a turntable. Work your way through the grits until the glass is at the required smoothness. You can get specialist polishing discs made of rubber or felt, or you may need to move to a different machine such as a cork or felt wheel to finish polishing the surface if this is required.