Half round, ring and marking files are exceptionally versatile machinist’s files The flat sides of a half round file can be used in the same way as a flat or hand file.
The acute angle created at the file edge where the semicircular and flat sides meet on half round and ring files can also be used in a similar way to a three square file for deburring and finishing internal corners.
What are the characteristics of half round, ring and marking files?
Cross section
Half round, ring and marking files have a semicircular cross section.
Their curved side allows for filing of concave surfaces and the insides of round holes.
This in turn makes them ideal for de-scaling pipes.
Ring files tend to be a little narrower than their other semicircular cousins so that they can fit into smaller spaces.
This is how they earned their name, as their narrower section allows them to fit inside rings more easily.
The rounded side of all of these files can be used to create curved grooves.
Profile
All of these files taper towards the point in width and thickness, which allows them to fit into small openings and confined spaces.
Cut
Half round and ring files are usually double cut on their flat side, but their rounded side can be single or double cut.
Marking files are safe on their flat face.
This makes them particularly useful for working on the inside of cuvres, as it is impossible to accidentally spoil the surface you are filing with the corner of the tool.
Size
Half round files are usually available in lengths from 100mm (4 inches) to 400mm (16 inches).
Ring files are usually 150mm (6 inches) long.
Marking files are usually between 137mm (51/2 inches) and 162mm (61/2 inches) long.
Swiss or American?
Half round files can be either Swiss or American pattern.
Ring and marking files are both Swiss pattern files.