Measuring Guide

The easiest way to determine what type of collet your machine has is to measure the length and diameter of the collet.  All collets have a distinctive length and diameter.  Use the chart below to determine the correct collet series for your machine. If you need advice, give us a call or send us an email, and one of our specialists will help you get the best performance out of your tooling. Ensure that you have the correct size for your CNC and the router bit being used. Damaged or worn collets, as well as improperly sized collets, lead to poor tool performance and premature wear.
Collet SeriesLengthDiameter
ER1118 mm (.708″)11.5 mm (.45″)
ER1627.5 mm (1.08″)17 mm (.67″)
ER2031.5 mm (1.24″)21 mm (.83″)
ER2534 mm (1.34″)26 mm (1.02″)
ER3240 mm (1.57″)33 mm (1.3″)
ER4046 mm (1.81″)41 mm (1.61″)
SYOZ 2034 mm (1.34″)20 mm (0.78″)
SYOZ 2552 mm (2.06″)35 mm (1.38″)
TG 7547 mm (1.85″)27 mm (1.06″)
TG 10060 mm (2.36″)35 mm (1.38″)
SD-20 mm SHODA52 mm (2.06″)20 mm (back side)
SD-C001 SHODA52 mm (2.06″)16 mm (back side)
SS-22 SHODA40 mm (1.58″)22.5 mm (.89″) OD
SD-C01552 mm (2.06″)24 mm (back side)
Collet TG

Collet TG series

Collet SYOZ 25


Collect sizing chart

Using the right size collet for your tool shank diameter is crucial. First, make sure that you look at the correct sort of collet to fit your machine’s spindle or tool holder. A common error is the attempt to fit a shank tool that’s too large into a smaller collet. It’ll go in, and you’ll be able to tighten it, but the collet will be stressed. This can cause vibration and imbalance causing the tool to leave a poor surface finish. It is also potentially dangerous to the operator should the tool break or be thrown from the collet.