The SK collet system has an 8° taper angle versus the 16° taper vs ER type collets which provides double the gripping force. Because of the narrower collet chuck, the SK collet results in better depth of cut. The nuts force is more vertical than ER Collet chucks so it will now misalign or rock in the chuck. Although range is .019 for most SK collets we recommend you not use more than .01 collapse.
ER8 series collets have a capacity of .020-.197 inches. Each ER8 collet has a range of .020 inches(0.5mm). The size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range of .020inches(0.5mm). For example, ER8-3mm can grab a round shank from 3mm diameter to 2.5mm diameter.
ER11 series collets have a capacity of .020-.3125 inches. Each ER11 collet has a range of .020 inches(0.5mm). The size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range of .020 inches(0.5mm). For example, ER11-3mm can grab a round shank from 3mm diameter to 2.5mm diameter.
ER16 series collets have a capacity of .015-.4375 inches. Each ER16 collet has a range of .039 inches(1mm). ER16 Collets .118 and smaller have a range of only .015 inches. The size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range mentioned above. For example, ER16-1/4 can grab a round shank from .250 diameter
ER20 series collets have a capacity of .015-.512 ie size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range mentioned abnches. Each ER20 collet has a range of .039 inches(1mm). ER20 collets .094 and smaller have a range of only .015 inches. The size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range mentioned above. For example, ER20-1/4 can grab a round shank from .250 diameter
ER25 series collets have a capacity of .015-.630 inches. Each ER25 collet has a range of .039 inches(1mm). ER25 Collets .094 and smaller have a range of only .015 inches. The size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range mentioned above. For example, ER25-1/4 can grab a round shank from .250 diameter.
ER32 series collets have a capacity of .02-.787 inches. Each ER32 collet has a range of .039 inches(1mm). ER32 Collets .094 and smaller have a range of only .015 inches. The size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range mentioned above. For example, ER32-1/4 can grab a round shank from .250 diameter
ER40 series collets have a capacity of .094-1.024 inches. Each ER40 collet has a range of .039 inches(1mm). The size indicated on the collet is the largest size it can hold and can be collapsed smaller within its collapse range mentioned above. For example, ER40-1/4 can grab a round shank from .250 diameter