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Expanding Collets
I have a part that requires internal gripping. What are my options?

"I have a part that requires internal gripping. What are my options?"
"There are two options--the "Master Expanding Collet" and the "Sure-Grip Collet-Style Expanding Collet". Both of these can be used in a 5C or 16C spindle. The Master Expanding Collet uses interchangeable pads which can be removed and stored. This unit is opened with a draw plug that actuates the collet in the front. It is mainly for light duty machining.

The Sure-Grip Collet-Style Expanding Collet system will also work. The collets are parallel opening and have a range of .125" to 4". This system, in larger sizes, can handle heavy duty machining operations." What is the operating range of a Quick-Change collet? The operating range is ± 1/64" (.393mm) when used on multi-spindle automatics for bar stock work. The operating range of the collets when used on CNC lathes is -1/64" (.393) to +.008" (.20 mm). Note that the best grip is with a full bearing, which is at the rated size of the collet. As the stock gets larger, the collet will grip at the edges of the slots; as the stock gets smaller, gripping will be at the center of the gripping surface.

Jones and Shipman Hardinge Limited
Murrayfield Road
LE3 1UW, England
Tel: +44 (0)116 2013000
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Hardinge is the leader in providing a wide range of highly reliable turning, milling, grinding and workholding solutions under the brands Hardinge, Bridgeport, Kellenberger, Hauser, Tripet and Tschudin. We never compromise on product design, so customers can count on Hardinge to help them make the right part to the required specification, every time.