Tip #56
Lathe Turning
Click here for a printer friendly version of Tip-
Pg. 1-4, Pg 5-8, Pg 9-12, Pg 13-16, Pg 17-20, Pg 21-23
Help with Downloading PDF Files

Holding Lathe Tools

Two ways to grip lathe tools properly (reverse if left handed) are demonstrated in Figure 12-4. The left hand is usually placed on top of the blade, with the little finger toward the stock. The butt of the hand or little finger rides against the finger ledge. The right hand holds the handle of the tool and provides the movement which determines the cut. The part of the hand that rests on the finger ledge also acts as a gauge.

An alternate method of holding the lathe tools consists of placing the left hand on the blade with the thumb on top. The back of the hand rests on the finger ledge and the fingers are placed comfortably around the tool or on the finger ledge. The right hand serves the same purpose in this holding method as it does in the method mentioned previously.

When making smoothing cuts or when roughing stock to size, the tool may be moved along the tool rest parallel to the work, taking a bite that remains constant because the left hand butts against the tool rest ledge and acts as a control.

The feed of the chisel, which determines the amount of wood removed, should be slow and steady--never forced, never jabbed into the work. After the tool is in position, start the cut by advancing the tool slowly until it touches the wood.

Three Cutting Actions
Each of the lathe chisels act in the three ways shown in Figure 12-5, depending on how you hold them.

Scraping--Scraping is the easiest and safest of the three actions and the best for the beginner to use. Many experienced operators use this action almost exclusively because it gives good results.

A scraping action with a round-nose chisel is shown in Figure 12-6. Notice that the hand position hasn't changed except for the fingers. Placed as shown, the thumb and forefingers do most of the gripping and help to bring the cutting edge of the chisel close to a horizontal plane. This position is maintained while the chisel is advanced to the depth of the cut and then moved slowly from side to side to increase the cut's width if necessary. Full depth does not have to be reached at once. The chisel may be moved forward a slight amount and then moved from side to side as the pivot point is maintained. The procedure is repeated until the full shape is formed. Each “pass” removes a little more wood.

Cutting--This action calls for bringing the tool edge into the surface almost as if it were a knife.

The feed should be slow and the cut should be light. Warning: If you jab the chisel into the work-piece suddenly or deeply, the chisel will be wrenched from your hands. You could be seriously injured. At the very least you will ruin the workpiece by cutting and lifting a large splinter from it. Don't use the cutting action until you have practiced enough with the scraping action to be thoroughly familiar with each tool and what it can do. Once you have become proficient with the cutting action, you'll find that it leaves a surface smooth enough to finish with a little touch-up.

Shearing--The shearing action is usually limited to the skew and gouge. It is a cutting action with the tool edge moved parallel to the work, taking a constant bite, shearing away a layer of wood from the surface of the stock. A shearing action with the gouge is illustrated in Figure 12-7. The shearing action of cutting beads with a skew is shown in Figure 12-8. Shearing a cove is one of the easier cuts. Since the tool is held on edge, move your thumb behind it to steady it while making the cut. When the gouge is sharp and properly held, wood is removed rapidly and the surface is left smooth.

While each of the tools does certain operations better, the overlap is so great that no hard-and-fast limitations can be set down for each one. Each tool will cut differently, depending on the action, the angle, and the way it is moved. Practice with each tool until you have the feel of each of them. When you arrive at this point, habit will take over and your use of the tools will become an individual application that is standard with you.

Using the Gouge
The gouge, one of the more versatile turning tools, can be used with any of the three cutting actions. At times it is applied so all three cutting actions come into play (Figure 12-9).

It is the only tool to use when doing initial rounding (Figure 12-10). This is essentially a shearing cut with the gouge held on its side and moved parallel to the work. Depth of cut is maintained by a finger resting against the tool rest ledge.

Rounding should be started somewhere along the length of the stock with the gouge moved in the direction indicated by the arrows in Figure 12-9E. You'll find it is easier to work from a midpoint toward each end of the stock instead of making one continuous cut from end to end.

To make rounding cuts in a limited area, use the gouge between sizing cuts made with the parting tool or marks penciled on the workpiece.

Figure 12-11 shows how you can use the gouge in a scraping action to form a cove whose size and shape is dictated by the tool. The gouge is held in a horizontal position and slowly moved directly forward. Warning: Do not remove too much material at once. Retracting the gouge frequently will allow waste material to fall away.

The shearing action is a more advanced way to form a cove with the gouge. Begin with the gouge on its side as if you were preparing for a rounding cut. Feed the gouge forward to contact the stock; then rotate it on the tool rest as you move it toward the center of the cove (Figure 12-12). Work this way from both sides of the cove toward its center. As the gouge is manipulated, the action changes from shearing to scraping (Figure 12-13), which occurs at the full depth-of-cut point only.

Using the Skew Chisel

Typical applications of the skew chisel are shown in Figure 12-14. While professionals use the skew mostly in a shearing action, it can function efficiently while cutting or scraping. A common scraping action is shown in Figure 12-14E with the chisel held to square off the end of a cylinder. When held this way, the chisel's sharp point removes material quickly and leaves a reasonably smooth surface. The same result is obtained by using the point of the skew in a cutting action (Figure 12-14B). When used this way, the skew works like a knife, severing wood fibers and leaving a surface that requires little sanding.

Tapers are formed by starting the cut with the heel of the blade and raising the handle as you slide the chisel along the tool rest. To smooth a taper that was formed with another tool, use the skew as shown in Figure 12-14A or F. This can be a scraping or a shearing action. If you move the skew so only its heel contacts the work-piece, it will shear. If you position the skew so its edge is parallel to the workpiece and then advance it while maintaining tool-to-work-piece contact, the action will be scraping.

Probably the smoothest surfacing cut of all is shown in Figure 12-14H where a shearing cut is being used to smooth a cylinder. The cutting edge of the skew is held at an angle to the longitudinal axis of the workpiece. When done correctly, the surface of the work-piece is smooth with a finish that looks burnished. It will take practice.

The skew is used to form beads. Like a cove, the bead requires three marked or imagined dimension lines: one to indicate the bead's center and one on each side of the center to indicate total bead width.

Start by placing the heel of the skew lightly on the bead's center-line so its edge is tangent to the curve you want to form. Move the skew into the workpiece. At the same time, rotate and lift the handle to follow the curve of the bead. It will take several passes to form one-half of the bead (Figure 12-15). Follow the same procedure, but work in the opposite direction, to form the other half of the bead (Figure 12-16).

Using the Roundnose Chisel
The roundnose chisel is always used in a scraping action (Figure 12-17) and is the only tool to use for hollowing. In the latter application, the tool rest must be positioned to provide maximum support for the chisel even if it has to be placed inside the hollow that is being formed.

Using the Parting Tool
The parting tool is most often used in a scraping action with the edge of the blade resting on the edge of the tool rest and with blade feed directly forward, whether the cut is square or at an angle to the work-piece (Figure 12-18).

The parting tool is often used to determine the depth of cut or the diameter of the final shape. To speed up the procedure when making preliminary sizing cuts, handle the tool as shown in Figure 12-19. Start with the tool horizontal, then slowly raise and lower its cutting edge as the cut deepens.

Continue to Planning the Design
Back to Lathe Tools