Collets offer a fast and accurate way to mount cylindrical parts or bar stock in a lathe. Each collet functions like a miniature precision 3-jaw chuck and fits into a tapered adapter mounted in the headstock. A drawbar passes through the headstock and threads into the rear of the collet, pulling it into the adapter. This action causes the collet jaws to close and securely grip the workpiece. Collets are known for their exceptional centering accuracy, but each collet size accommodates only a limited diameter range—typically ±.001" (0.02 mm).
WW Collets vs. Milling Collets
Unlike milling collets, WW collets feature a through-hole, allowing material to pass completely through both the collet and drawbar. The maximum diameter stock that can pass through is 3/16" (4.5 mm), although WW collets are available in sizes up to 5/16" (8.0 mm). Collets larger than the through-hole capacity are sometimes referred to as “pot chucks,” as they are only bored to a depth of approximately .260".
Collet Accuracy
Sherline WW collets are precision-made and have a maximum runout of .002" or less. When the WW collet adapter is properly trued as recommended in the instructions, runout is minimized, providing optimal accuracy. Pot chucks (collets larger than 3/16" or 4.5 mm) are not bored through and may exhibit increased runout if your part extends far beyond the front of the collet.
Logical Part Numbering
Sherline collets are organized by size for easy identification:
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Inch Collets: Part numbers begin with 1160, followed by two digits representing the size in 64ths of an inch.
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Metric Collets: Part numbers begin with 1178, followed by two digits representing the size in 0.1 mm increments.
Compatibility and Specifications
Sherline WW collets are manufactured in-house to standard WW specifications but are not hardened. The shank diameter is .312–.313", and the thread is .275-40. While some third-party WW collets may not fit properly, Sherline offers an optional .315" adapter and drawbar set (P/N 1163) to accommodate select 8 mm collets from other manufacturers.
Available Sizes
Sherline WW collets are offered in:
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Inch sizes from 1/64" to 5/16", in 64th-inch increments.
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Metric sizes from 0.3 mm to 8.0 mm, in 0.1 mm increments.
Special inch sizes up to .320" can be custom ordered with approximately a 3-week lead time. Please contact us for details.
Quck Order
If you are ordering a lot of different size collets please use the quick order table below to make it easier!
