Collets
In the world of machine tools, collets are a type of clamp – a chuck – that holds a tool or workpiece. As such they are a vital part of the operation. They are the link between the fixed machine (the motor, gears, spindles, drive and bed of a lathe, drill, mill or other piece of equipment) and the specific bit being used to perform the required operation.
Chucks allow the bit or tool to be swapped, so one machine can perform multiple jobs (imagine if every drill could only make holes of one particular size!). They also ensure that the bit or other tool is held securely and centrally for accurate work.
Read MoreCollets use an expanding sleeve of spring steel with a cylindrical inner surface and a conical outer surface. The tool or workpiece fits against the inner surface and the outer surface fits into the machine. The conical outer surface is tightened down with an external nut, contracting the inner surface around the tool or workpiece with an even, secure and self-centralising pressure.
Collets are generally held to be the most superior form of chuck for machine tools. Of the major types of chuck, they are the only ones that simultaneously and reliably provide a strong clamping force, self-centring effect with very low run-out, resist loosening and yet allow tools to be changed quickly. While other forms of chuck allow one clamp to fit a wide range of sizes of tool, collets have to be made for specific tool sizes or a narrow range of sizes.
Therefore, a machinist or workshop will have to purchase a set of collets – a higher initial cost. But each collet will perform better when matched with its designed tool size than a (literal) one-fits-all scroll chuck. The initial cost is offset by more consistent quality and faster output.
Rennie Tool provides a range of high-quality ER spring collets. Since their invention in the 1970s, the ER collet system has become the preferred tool holding system around the world. They were developed for holding tools, especially drills. Therefore, their design is optimised for holding round-section drill bits and withstanding axial loads (up and down the long axis of the tool). They can also perform well when holding round-section workpieces with light cutting forces.
Rennie Tools makes and supplies ER collets in a wide range of sizes, from ER11 to ER32. We can also supply sets of ER collets in metric and imperial sizes with nine, 12, 14 or 19 collets in each set. So, whatever your demands or work, you can find the ER spring collets you need.
Our collets are made from high quality spring steel, with design and manufacturer to ensure run-out tolerances of less than 0.008mm.
Buy the best ER collets and ER collet sets for your needs from Rennie Tool Company. We can despatch your order from our Manchester factory the day it’s placed, and we offer worldwide shipping. Contact us today for more information or to place an order.
