This chuck is identical to P/N 1040 except for an electroless Nickel-Teflon coating that has been applied to help prevent wear and corrosion. This special coating has been applied to all external and internal surfaces of the chuck (except for chuck jaws), significantly improving the life of the chuck. This chuck also opens and closes more smoothly due to the lubrication properties of Nickel-Teflon.
- Ductile plating with columnar structure
- Harder than any other nickel-based coating
- Coating uniformity that eliminates post-plate grinding (or burnishing)
- Wear properties overall superior to hard chromium
- Hardness (68-72 Rc)
- Low coefficient of friction (.044) Teflon™ is .04
- Uniform coating thickness up to .004”
- Accepts dry film lubricants
- 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/special instructions” box, on this page, when checking out.
- Soft (unhardened) steel jaws are also available upon request (No extra charge). They are not stepped so they can be machined by the customer for custom holding applications. Because of this the jaws tolerances are not held to the same standard as our standard chuck jaws. Add the note “soft jaws” to the “comments/special instructions” box, on this page, when checking out.
- Interchangeable top jaws are also available.
- Chuck Diameter - 3.1″
- Jaw Capacity -
With jaws in normal position: 3/32″ (2mm) – 1-3/16″ (30mm)
With jaws in reverse position: 1/4″ (6mm) – 2-3/4″ (70mm)
- Through Hole Diameter - .687″ (17mm)
- Thread Size - 3/4-16
- Chuck Body Material - 12L14 Steel
- Chuck Jaws Material - 12L14 Case Hardened Steel
- Coating - Electroless Nickel-Teflon
How to Distinguish between Standard Chucks and Coated Chucks
Some of our customers have been wondering how to tell the difference between our standard chucks and those that have the electroless Nickel-Teflon coating. Standard chucks have darker markings than the coated chucks (See Figure 1. Click on photo to view a larger image).
Figure 1—Examples: (Left) 1040 3-Jaw Chuck (3.1″), (Right) 1040C Electroless Nickel-Teflon Coated 3-Jaw Chuck (3.1″)
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 noticably 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.
Removing a Stuck Chuck from the Spindle
Use one tommy bar in the hole in the spindle and another tommy bar in a hole in the chuck body to achieve enough leverage to unscrew the chuck (counter-clockwise) from the spindle thread. If the chuck becomes stuck on the spindle thread, put a tommy bar in the hole in the chuck body. Place a block of wood against the tommy bar where it enters the chuck. With a small mallet, give the block of wood a sharp tap, turning the chuck in a counter-clockwise direction. It should not be necessary to hold the spindle, as its inertia should be sufficient. (Don’t hit the tommy bar anywhere other than right where it enters the chuck or you could bend it.) This small but sharp force at the outer edge of the chuck should break the thread loose and the chuck can then be unscrewed by hand.
Download PDF 1040 Instructions