While we have casually mentioned lathes, turning, and turnery in some of our past articles, we’ve never really written about lathes in detail. Today we will dip our toe in that water a little bit more than we have previously. The thrust of the piece will be on lathes in the woodworking shop rather than lathes in the machine tooling shop (wood, not metal).
What Is A Lathe?
Lathes are machine tools that rotate a piece of wood, usually a piece of wood that has not been worked extensively or shaped or milled. The wood is rotated around an axis while you cut, knurl, drill, shape, and sand with tools that are designed specifically for those various tasks in order to create a finished product that is symmetrical around that axis.
If you need a visual reference, think of a table leg. A piece of wood the length of the leg but otherwise and usually square along its span is attached to what is called the headstock and resting at the other end on or in a tailstock. The piece of wood is then spun or rotated at a fairly high and constant speed while the wood is “worked on” with tools designed for the purpose.
Material is removed by those tools as the wood rotates, and the wood piece is shaped as designed for that table leg. Different tools are used in the process of shaping the piece of wood as desired. Its form is refined and sanded, and the piece is readied for your choice of finish.
Lathes have variable speeds, depending on the stage of shaping the workpiece. Lathes have a tool rest that stabilizes the tools, supporting and guiding them along the span of the wood as it is shaped, smoothed, and sanded.
Types of Lathes
Depending on who you speak with, there are anywhere from 4 to eight different types of lathes. We won’t go into detail for each one of them, but will touch upon some of them lightly here:
- Center lathe. Commonly used for turning, grooving, and knurling. Grooving is exactly what you would expect: creating grooves on the wood. Knurling involves creating straight, crossed, or angled lines on a piece of wood.
- Speed lathe. Commonly referred to as a wood lathe, this high-speed model has variable speeds that range from 1200 to 3600 RPMs and allows work on the wood all the way from rapid material removal to the finer touch of smoothing and sanding.
- Turret lathe. This is the big brother of the speed lathe and is used for high-volume production but performs the same functions as the speed lathe.
- Bench lathe. Exactly what the name suggests, this is a smaller version of the speed lathe that is well suited for small turnery jobs and will fit on your workbench.
- Special lathes. Included in this type are vertical lathes, where the workpiece is held vertically in place rather than horizontally, as in the other types of lathes used for heavy-duty production.
- CNC lathes. Computerized operation separates this type from all the others. A program is developed and installed into the computer interface of the lathe, and it turns out (pun intended) identical, mass-produced pieces.
To this list, we will add the chucker lathe.
Chucker Lathes
In all of the previously mentioned lathe types, one end of the workpiece is attached to the headstock, and the other is attached in some fashion to the tailstock. The lathe then spins or rotates the piece of wood, and it is worked on while spinning on its axis.
What is a Headstock?
The business end of the lathe, the headstock, supports one end of the piece of wood and spins it. The piece of wood is attached to it firmly so it will rotate on its axis. The motor of the lathe turns the headstock, and that turns the wood.
What is a Tailstock?
The tailstock of a lathe supports the other end of the wood and holds it level and steady as the headstock turns and the wood rotates on its axis. While the wood is actually attached to the headstock, it is merely supported by the tailstock. The motor only powers the headstock.
Unlike the headstock, which is stationary, the tailstock can be moved to accommodate the size/length of the piece of wood being turned. It merely supports the wood and does not turn it; that is the job of the headstock.
How Does a Chucker Lathe differ?
A standard chucker lathe differs from other types of conventional lathes in that there is no tailstock
On your power drill, the drill bit is secured to the drill within a chucker. The chucker grips the drill bit and holds it in place as the bit spins and does its work. The drill chuck holds the rotating bit, the lathe chuck holds the rotating wood.
The lathe chuck clamps onto the workpiece with jaws that will hold it tightly in place as the headstock turns. Thus, there is no need for a tailstock to offer support for the workpiece.
Just as the chuck on your power drill is tightened to hold the drill bit in place, so does the chuck on the lathe. The clamping can be tightened or loosened with a chuck key or hex wrench. The drill chuck is smaller, though, and can be turned by hand. The principle, though, is the same.
If you are turning a bowl, for instance, it needs to be held in place in one spot; you need access to the front of the wood piece to create the bowl’s depth. The chuck is adjusted to hold the piece of wood at what will be the bottom of the bowl while you shape and size its outside and create the inside space that will hold the salad, for instance.
The three-jaw lathe chuck, one of the common chucks for lathes, is used because of its ability to self-center the pieces of wood. It’s a very convenient chuck commonly used because of that feature.
Here’s a basic lathe chucks video to help understand lathe chucks more clearly. It’s not long and gives a clear picture of what they are and how they work.
Those of you who are engaged in turnery already know what a chucker lathe is and perhaps have turned out bowls using a lathe chuck. The analogy to power drill chucks and bits is an apt one and makes clear the chuck’s purpose on a lathe. Anyone who’s turned out a bowl knows that.