Lathes are fantastic pieces of equipment; while experienced professionals can produce magic on them, even inexperienced amateurs can produce competent and good-looking projects. A well-turned piece of wood can often make the difference between an average project and a unique piece of art.
Lathe tools need to be very sharp, and before being used, you must test your lathe tools to ensure they are sufficiently sharp; if they aren’t, you need to sharpen them before carrying on. These tools will need to be resharpened for every fifteen minutes of turning hardwood.
When a lathe tool takes you more time to cut through a section, or they produce a different sound than usual; it makes chips instead of strands; you need to apply more pressure to force your tool into the wood when turning it; the blade of your tool has probably lost its edge and has become dull.
Lathe Tools Should Be Very Sharp
A lathe tool needs to be very sharp to achieve the cut and fit, which will satisfy you, and if the lathe tool is not sharp enough, it will result in wood tearing. Depending on where you are in the cutting process, you can use less sharp roughing gauges, but the finishing cuts require a very sharp tool.
It is very satisfying to work with a sharp tool and watch the shape effortlessly appear as you work with the wood.
The tool’s blade will become dull more quickly than you may imagine. The edge works very hard; for example, if you turn a piece of wood with a 6.5″ diameter and use a speed setting on the lathe of 600 rpm, 200 inches of wood will pass over the tool’s blade per second.
How Can You Tell If Your Lathe Tool Is Not Sharp Enough?
You need to test your lathe tool’s sharpness before the effects of a dull blade begin to show on your project.
The Lathe Tool Paper Test
Apply the cutting tool’s edge to a piece of paper. To cut it cleanly, it needs to be very sharp. It needs to be sharpened if it tears the paper rather than cutting it.
The Lathe Tool Reflection Test
With this test, hold the cutting edge up to a light source and see if any light reflects off the cutting edge (not the side of the tool). If the light is reflected off the cutting edge of the lathe tool, it means that there is a flat spot on the cutting edge, and it needs to be sharpened.
If the edge is not distinct from the side of the tool, it means that the edge is sharp enough.
The Lathe Tool Finger Test No 1
Hold the lathe tool upside down next to your body and carefully run your finger across the cutting edge. If it is sharp enough, it will not slide smoothly across the blade because the sharp edge is catching on the rough skin of your finger.
Please note, to conduct this test, you must pass your finger at 90 degrees to the cutting edge and not in parallel to the edge. Passing your finger parallel to the cutting edge may cause you to injure yourself.
The Lathe Tool Finger Test No 2
Drag the tool over your thumb’s fingernail. If the edge is sharp enough, it will catch on the surface of your nail and even produce some nail shavings!
If it passes over quickly with no friction, it needs to be sharpened.
Try Carving A Little Off-Cut Of Softwood
Take a piece of softwood, like pine, and try to cut down across the grain with the lathe tool. If the lathe tool cuts through the grain evenly, then the lathe tool is sharp enough.
If it only pushes down, doesn’t cut the surface, and creates a dent in the wood, the lathe tool needs to be sharpened.
What Factors Influence The Sharpness Of Your Lathe Tool?
Several factors impact how quickly a blade tool loses its sharpness. These include
The Type Of Wood You Are Turning With Your Lathe Tool
If you turn very hardwood that scores highly on the Janka scale, and if it has a lot of imperfections, in particular, the lathe tool will lose its edge more quickly.
The softer or moister the wood is, the longer it will hold its edge.
The Type Of Lathe Tool You Are Using
Due to the nature of their functions, some tools in your box will lose their edge more quickly than others.
The roughing gauge tool, which starts the basic shaping of the wood, will be worn more quickly than a parting tool.
The Metal It Is Made From Influences The Length It Stays Sharp
Lower cost consumers lathe tools are made from High-Speed Steel or an iron alloy with tungsten. High-speed Steel and Iron Alloy tools will wear the fastest and need to be sharpened more frequently.
Higher quality, more expensive tools fall into the category of “crucible steels,” also called ‘Powder metal’ are made from chromium, cobalt, vanadium, or carbon.
Carbon steel gets a sharper edge but does not have the wear resistance provided by the chromium, cobalt, or vanadium carbides produced in crucible steels.
Of course, the downside of hard lathe tool materials is that the harder the material, the more difficult it is to sharpen.
How Do You Sharpen A Lathe Tool
Sharpening lathe tools is a whole subject, and there is not enough room in this article to do any justice to this complicated subject.
Instead, let’s look at the principles which you should apply.
You Need To Sharpen The Tool, Not Reshape It
When you sharpen the lathe tool, the intent is to make the edge sharper while maintaining the shape of the original edge.
Be careful to hold the lathe tool at the correct angle to the table grinder so that the edge becomes sufficiently sharp.
Sharpen both sides of the blade so that the angles to the blade remain consistent across both sides.
How Can You Sharpen A Blade So That It Stays Sharp
Even though razor-sharp tools are great to work with, the sharper you make them, the quicker they will lose their sharpness. Using the example of a razor blade, in the beginning, it cuts almost magically; however, it does not take long before it loses its edge.
If you sharpen the lathe tool to the point where it passes the tests detailed earlier in this article, namely;
- The Lathe Tool Paper Test
- The Lathe Tool Reflection Test
- The Lathe Tool Finger Test No 1
- The Lathe Tool Finger Test No 2
- Carving A Little Off-Cut of Softwood
It is sharp enough, and you can use it for your project.
Only sharpen the tools to the level they need to be sharpened. Roughing gauges do not need to be as sharp as parting tools.
Conclusion
Without lathe tools, lathes are lumps of metal with no purpose. The different lathe tools applied appropriately to the wood being turned can create the most beautiful artistic wooden projects.
It’s critical; however, the lathe tools are sharpened as much as needed, and that you regularly monitor the lathe tool to resharpen it as often as you need.