Grinding cutting tools

Why does metal edging need to be removed from tools ?

Whether it is on the head of a pointed chisel or a mason’s chisel, on the head of a splitting wedge and  sometimes on the striking face of a sledgehammer or a maul, after a while you will see metal  edging appear and this will gradually crack around the outside.

This edging is dangerous because it is usually sharp and small splinters of metal can come off and injure the user or a person in the immediate vicinity.

Edging on  chisels and wedges

On chisels and wedges  edging is normal because these tools are lightly hardened : you must regularly trim the surface,  put back the original chamfer and round the edges by  removing the metal edge with a file or grinder.  When grinding, take care not to overheat the surface as this may destroy  the heat treatment on the tool.

Edging on sledgehammers and mauls

Regarding sledgehammers and mauls, the appearance of edging can have two different causes:

· If the edging appears very rapidly with cracks appearing after one hour of use, there may be a defect in the metallurgy or heat treatment of the tool. In this case, you must stop using the tool and ask for a replacement under guarantee from your store.

. However if there is slight edging without cracks after intensive use of your tool, it is normal wear and tear which appears when two metal surfaces are struck on one another. You just need to trim the surface, put back the original chamfer and round the edges with a file or grinder.

Yes,  a grinding machine may be used, but be careful

In all cases, when using  a grinding machine  you must first read the safety instructions in the instruction manual of the machine and avoid any overheating of the surface that you are grinding, as this may remove the hardening obtained by the original heat treatment.