As a new owner of a small-sized metal lathe, I was wondering if I could use this lathe also for small woodworking projects. After spending the money and dedicating the space for the machine, I thought, I had better to put it to maximal use.
Through testing and trying the lathe with different tools and different woods, I can tell you the answer: a metal lathe can be used for woodturning with small projects that fit into the machine. Some modifications and adjustments are necessary, however, depending on the type of cutting you wish to do, and extra precautions must be taken to ensure proper workpiece holding, dust collection, and operator safety.
I will next go through the main points that I think you should consider if you wish to use your metal lathe for wood. I hope the information will help you make the most of your machine!
Warning: operating a lathe carries a risk of injury – be sure to wear the appropriate personal protective equipment, read all instructions, and exercise caution; please also see the Disclaimer.
Metal lathes are usually intended for smaller workpieces than wood lathes of the same outer dimensions and power. The shorter distance between centers and the narrower swing mean that they are best suited for small-sized wood turnings such as pencils, small bowls and cups, candle holders, and perhaps chair legs. Sadly, most wooden bowl or table leg projects are unlikely to fit into the small-to-medium sized metal lathe that you would typically have in your shop.
That said, metal lathes usually have more than enough power and stability for their size, so these will not restrict the speed or depth of your roughing cuts.
The easiest way to turn wood in a metal lathe is to use the carriage, tool holder and tools just as you would with metal. Your typical HSS or carbide tooling will not have any problems in cutting wood, and allow you to perform the typical OD, facing and ID work on wooden workpieces as with metal.
Obviously, this method is not very well suited for producing the more elaborate and rounded and undulating shapes that are typical in wood turnings. Neither will it produce the plane-smooth finish that can be achieved with woodturning chisels; the metal tools cut wood in a scraping manner, and leave a much rougher finish, particularly with softwood workpieces.
If you want to turn wood in a metal lathe with conventional woodturning tools and style, you will have to improvise a tool rest into your metal lathe. While this takes some work, it is not difficult, and the tool holder provides an easy adjustable mount point for the rest. For safety, it is important to ensure that the tool rest retains sufficient clearance to the chuck.
3 Workpiece holding
Most metal workpieces can take large gripping forces and surface pressures without any issues, and this allows you to tighten them into the lathe chuck very securely.
This is not the case with wood, which is easily dented, particularly in the cross grain direction. Using the standard metal lathe chuck to hold wooden workpieces is therefore a balancing act: grip too tight, and you will mark your piece; grip too loosely, and the piece may come flying off the chuck. With some experience, you can develop a feel to the appropriate tightness and use the standard three- or four-jaw chuck successfully with wood. If you are unsure of the proper tightness as you are starting out, it is better to err on the side of caution and grip very tight.
With some ingenuity, it is usually possible to come up with various “soft jaws” or fixtures which enable you to grip wooden workpieces securely but without leaving marks on critical surfaces that will be finished. When using the standard chuck, I would also recommend planning your work, whenever possible, so that you can grip a feature of the workpiece that is not a part of the final product.
4 Dust collection
Cutting wood in a lathe, whether a wood or a metal lathe, generates dust and shavings. Compared to the metal chips resulting from normal metal lathe operations, the wood dust is more easily carried with air currents everywhere on, and possibly in, the machine. While woodturning lathes are typically designed to cope with wood dust, metal lathes are not, and the dust flying around may become a serious issue.
To avoid wood dust from clogging up you machine, I highly recommend that you have some sort of dust extraction in operation close to the workpiece. Ideally, you should arrange the collection so that all dust and shavings are extracted right at the point of generation. You can achieve this by fixing your shop vac hose, for example, close enough to the cutting point. In doing this, however, remember to ensure that the extractor head always maintains a sufficient clearance from both the workpiece and the chuck.
As mentioned, gripping the workpiece securely in the metal lathe chuck is somewhat more difficult with wood than metal. Further, a wooden workpiece is inherently more prone to splintering than a metal one.
Turning wood in a metal lathe therefore always carries some risk of the workpiece fracturing or coming loose. Such an event has a major potential of causing injury to you as the lathe operator, and damage to the machine. As with turning wood in a proper wood lathe, you should always wear a full-face mask and heavy clothes to protect yourself from workpieces turned into projectiles.
While a metal lathe cannot replace a wood lathe, it does lend itself to use in many small woodturning projects, provided you are willing to make some adjustments and take a few precautions. Although you can equip it with a tool support for woodturning with conventional style, it is the easiest to use with small geometrically simple items, which you can cut with metal tooling and straight tool paths. Personally, I have used my small metal lathe successfully for turning oak tealight holders of many different designs.