Collet
Before understanding ER collets you should know what is a collet .
A collet is a clamp-like holder that can exert a great force onto an object onto which it is tightened.
ER collet
The ER collet system is the most popular clamping system that is widely used for different applications.
Formerly they were referred to as “E” collets and were standardized according to alphabetical order.
Later Rego-Fix, a Swiss precision tool manufacturer, modified E collet, then patented and marketed it as ER collet, where “R” stands for Rego-Fix.
ER collets are commonly used in CNC machines as a tool holder for high precision drilling, آسیاب, and grinding applications.
ER Collet Design
A nut and a threaded body shaft together make an ER collet system.
The tool is inserted onto the collet with the nut already in place, this is because the end mill or router bit may deform nut bearings.
Inserting the cutting end of the tool into the collet can damage the collet.
Once the tool is inserted the nut is tightened and the collet system tightens around the tool shank which provides a great grip on the tool and is held well in place.
If you are someone who has been dealing with ER collets, you would have come across the DIN-6499 standardization.
ER collets are standardized internationally as ISO-15488, but in the marketplace, it’s mostly referred to as DIN-6499 which is the same but a German standardization.