2.5″ 4-Jaw Independent Chucks – Various Thread
Includes hex key, not pictured
These chucks have four advantages over 3-jaw chucks.
- They can be used to hold irregularly shaped parts
- They can be used to center parts with a great deal of accuracy
- 4-jaw chucks can be used to deliberately hold a part off-center
- They can clamp stock tighter
This is a valuable asset when machining cams, crankshafts, and similar parts. The main disadvantage of the 4-jaw independent chuck is that the jaws must be set individually, adding considerable setup time. The jaws are reversible to accommodate larger stock.
NOTE: The independent chucks don’t have Tommy bar holes like the scroll chucks because most people use the 5/32″ hex wrench into one of the jaw screws to thread the chuck on and off. Our P/N 3020 5/32″ Hex T-Driver works perfectly.
Like the Sherline 3-jaw chucks, the 4-jaw chucks can clamp either externally or internally. Although we recommend the 3-jaw chuck for standard lathe projects, the 4-jaw chuck is considered the accessory that could add the most versatility to your machine. If you feel the 4-jaw chuck would be more useful, and you have no need for the 3-jaw chuck, any lathe “A” package can be ordered with the 4-jaw chuck substituted for the 3-jaw upon request. A clamping groove allows the chuck to hold parts for milling.
Chucks for Sherline and Other Lathes
The chuck is available in several spindle threads for use on Sherline (3/4-16) and other machines, such as old Unimat lathes (12 mm x 1 mm and 14 mm x 1 mm) or Sears 6″ lathes (1/2-20).
*Please note that chucks with a thread size other than 3/4″ x 16 are made to order and have a lead time of 5-7 business days.
Jaw Options
- For those who have jobs where speed and ease of use are more important than maximum accuracy and want a chuck that is loose right from the start (No extra charge).
Add the note “loose jaws” to the comments box below - Soft (not hardened or machined) steel jaws are also available when you build your own chuck.
-
| Chuck Diameter | 2.5″ |
|---|---|
| Jaw Capacity | With jaws in normal position: 3/32″ (2mm) – 1-3/16″ (30mm) With jaws in reverse position: 5/16″ (8mm) – 2-1/4″ (56mm) |
| Through Hole Diameter | .687″ (17mm) |
| Thread Size | P/N 1044 – 3/4-16 (Sherline) P/N 1071 – 12mm x 1mm (Unimat SL 1000) P/N 1073 – 1/2-20 (Old Sears 6″ Lathes) P/N 1035 – 14mm x 1mm (Unimat 3 or Cowells) |
| Chuck Body Material | 12L14 Steel |
| Chuck Jaws Material | 12L14 Case Hardened Steel |
| Part No. | Description | Quantity |
|---|---|---|
| 10441 10711 10731 10351 |
2.5″ 4 Jaw Independent Chuck Body 3/4-16 Thread *Not sold separately 2.5″ 4 Jaw Independent Chuck Body 12mm x 1mm Thread *Not sold separately 2.5″ 4 Jaw Independent Chuck Body 1/2-20 Thread *Not sold separately 2.5″ 4 Jaw Independent Chuck Body 14mm x 1mm Thread *Not sold separately |
1 |
| 11451 | 4 Jaw Independent Chuck Jaw* | 4 |
| 11460 | 4 Jaw Independent Chuck Screw | 4 |
| 40550 | 5/32″ Hex Key | 1 |
*Because chuck master jaws are factory ground to precisely match each chuck body you must send your chuck back to us to be fitted with new master jaws. Please contact us for instructions on how to return your chuck.
Related products
- For those who have jobs where speed and ease of use are more important than maximum accuracy, and want a chuck that is loose right from the start (No extra charge). Add the note “loose jaws” to the comments box below
- Soft (not hardened or machined) steel jaws are also available when you build your own chuck.
- 1 1/4" x 1" steel dowel pin that is used to adjust the jaws during installation and to chuck up on while boring and turning the jaws
- 1 1/8" hex key for tightening the 4-40 x 3/8" jaw mounting screws
- 2 spindle or "Tommy" bars for loosening and tightening the chuck
- They can be used to hold irregularly shaped parts.
- They can be used to center parts with a great deal of accuracy.
- 4-jaw chucks can be used to deliberately hold a part off-center.
- They can clamp stock tighter.
- For those who have jobs where speed and ease of use are more important than maximum accuracy and want a chuck that is loose right from the start (No extra charge). Add the note “loose jaws” to the comments box below
- Soft (not hardened or machined) steel jaws are also available when you build your own chuck.


2.5″ 4-Jaw Chucks – Various Thread
Includes 2 tommy bars, not pictured
This chuck combines the ease-of-use advantages of the 3-jaw chuck with some of the advantages of a 4-jaw chuck. It will automatically center square or round stock. (The stock must be accurately shaped for all four jaws to grip.) It will also grip thin-wall tubing in four places rather than three, which spreads out the load and allows more grip without crushing the tubing.
Turning the knurled portion of the outer diameter of the chuck scrolls all four jaws in unison. Included with the chuck are two Tommy bars for tightening and loosening the chuck.
Centering accuracy on self-centering chucks is to within a few thousandths of an inch. If perfect centering accuracy is required, see the section on 4-jaw independent jaw chucks.
This chuck will hold parts from 3/32" in diameter up to 1-3/16" with jaws in the normal position and up to 2-1/4" with the jaws reversed.
Chucks for Sherline and Other LathesThe chuck is available in several spindle threads for use on Sherline (3/4-16) and other machines such as old Unimat lathes (12mm x 1mm and 14mm x 1mm). *Please note that chucks with a thread size other than 3/4" x 16 are made to order and have a lead time of 5-7 business days.
Jaw Options

3.1″ 4-Jaw Chuck with Pie Jaws
Includes a steel dowel pin, hex key, and 2 tommy bars, not pictured.
This chuck features a Electroless Nickel coated chuck body for durability and rust resistance.
Included with the chuck and jaws:Because the jaws are meant to be bored to size for particular jobs, eventually they will need to be replaced. The replacement set P/N 1143-4P can be installed on your existing 1076C Electroless Nickel coated chuck body and master jaws. They are NOT intended for use on the standard 1076 chuck body.
NOTE: These jaws are designed to be used ONLY on our Electroless Nickel coated chuck P/N 1076C, and master jaws are custom fitted to each body, so master jaws (11445-P) are not available for purchase separately.
Why pie-shaped jaws?First developed by watch and clock makers, chucks with pie-shaped jaws offer two main advantages. Boring the unhardened jaws to hold a particular diameter part means that instead of gripping the part at only three or four tiny contact points, they grip the part all the way around its diameter. This increased gripping area allows for much less clamping pressure and less chance of deforming a gear or other delicate part held in the chuck. In addition, because the face is bored to an exact and consistent depth, placing additional parts in the chuck for turning or milling means each part surface is held at exactly the same depth as the previous parts, saving setup time.
Use on ornamental turning lathesWe decided to make pie jaws for our four-jaw self-centering chuck after a request by David Lindow, the owner of Lindow Machine Works, Maker of Modern Rose Engine Lathes, (https://lindowmachineworks.com/lindow-rose-engine-menu/). Ornamental turners need a chuck that can firmly grip wooden stock without damaging the surface. In addition to David’s request, we had also received several requests from our horological customers who were looking for a chuck similar to the Swiss-made watchmaker's scroll chuck. We designed our pie jaws in both form and function after the Swiss chucks.
How to Distinguish between Standard Chucks and Coated ChucksSome of our customers have been wondering how to tell the difference between our standard chucks and those that have the Electroless Nickel coating. Standard chucks have darker markings than the coated chucks (See Figure 1. Click on photo to view a larger image).
[caption id="attachment_4231" align="aligncenter" width="300"]
Figure 1—Examples: (Left) 1040 3-Jaw Chuck (3.1″), (Right) 1040C Electroless Nickel Coated 3-Jaw Chuck (3.1″).[/caption]
Here, at Sherline Products, each of our chucks is laser engraved with a company mark, chuck size, and jaw location. During the laser marking process the laser removes a bit of the surface and darkens the material below (Figure 1, left). When chucks are sent out to receive the Nickel-Teflon finish the coating process changes the dark engraved markings to a noticeably lighter finish (Figure 1, right).
There is also a subtle change in the color of the chuck, but in the absence of being able to compare them side by side, the most evident way to tell whether you have a coated chuck, or not, is to check the color of the laser markings.


3.1″ 4-Jaw Independent Chuck – 3/4-16 Thread
Includes hex key, not pictured
These chucks have four advantages over 3-jaw chucks.
This is a valuable asset when machining cams, crankshafts and similar parts. The main disadvantage of the 4-jaw independent chuck is that the jaws must be set individually, adding considerable setup time. The jaws are reversible to accommodate larger stock.
NOTE: The independent chucks don't have Tommy bar holes like the scroll chucks because most people use the 5/32" hex wrench into one of the jaw screws to thread the chuck on and off. Our P/N 3020 5/32" Hex T-Driver works perfectly.Like the Sherline 3-jaw chucks, the 4-jaw chucks can be used to clamp either externally or internally. Although we recommend the 3-jaw chuck for standard lathe projects, the 4-jaw chuck is considered the accessory that could add the most versatility to your machine. A clamping groove allows the chuck to hold parts for milling.
Jaw Options





