Bowl gouge basics are the foundation of wood bowl turning. The bowl gouge is probably the number one most recognized wood turning tool and for a good reason.
What is a bowl gouge? A bowl gouge is a hand tool used to cut and shape wood bowls on a lathe. The bowl gouge consists of a handle connected to a sturdy metal shaft. The metal shaft has a center groove along the top portion known as a flute. The leading edge, or tip, of the bowl
A bowl gouge can be used to make an entire bowl without the aid of any other turning tool if needed.
It is better to have multiple bowl gouges of different sizes and different grinds to make wood bowl turning as efficient as possible.
In this article we are covering the following topics:
- Parts of a Bowl Gouge
- Steel Used To Make Bowl Gouges
- Bowl Gouge Shapes
- Bowl Gouge Sizes
- Bowl Gouge Basics – Grinds
- Bowl Gouge Basics – Uses
- Shaping A Bowl Gouge
- Sharpening A Bowl Gouge
- How To Use A Bowl Gouge
- Four Bowl Gouge Cutting Techniques
Let’s jump in and start with identifying the various parts of a bowl gouge.
Bowl Gouge Basics – The Parts
The Cutting Tip
The bowl gouge is a pretty simple tool, but let’s take a closer look and identify all the parts.
At the tip of the bowl gouge is the cutting edge. The cutting edge is the entire curved area around the top edge of the gouge bevel.
Gently rubbing your finger against the cutting edge reveals how sharp it can be.
Directly under the cutting edge, on the outside, is the flat, smooth bevel surface. The bevel is used as a skid or guide when we “ride the bevel.” Keeping the bevel close to parallel to the cutting surface is the key to this technique.
At the bottom of the bevel, opposite of the top cutting edge is the heel. Most of the time the heel is not a critical component. However, if you cut a tight curve, the heel can interfere and actually burnish the wood as it rubs the surface.
To eliminate this rubbing effect of the heel, the heel area can be ground back making the bevel narrower and capable of turning tighter curved areas.
The shank or shaft of a bowl gouge is formed from steel rod that is then milled to shape and hardened.
In the center of the bowl gouge is the hollowed out concave area called the flute. This area is usually ground out of the solid steel as part of the gouge milling process.
Handles for bowl gouges are traditionally made from hardwood, but can also be made from metal or other materials.
The length of a bowl gouge handle contributes to the balance and leverage available when turning.
More massive bowl gouges, designed for removing larger amounts of material at one time, typically have longer and heavier handles which increase leverage advantage for the turner.
Most wood-handled tools usually have a ferrule or collar around the wood end where the shaft or shank connect.
A ferrule, many times made of metal, prevents the wood handle end from splitting.
Steel Used To Make Bowl Gouges
The steel used to make the bowl gouge shaft or shank can be made from many different metals.
Older gouges were made of high-carbon steel and required sharpening often, which wore the tool down quickly.
Today, the most commonly used bowl gouge steel is known as High-Speed Steel or HSS. HSS is a steel alloy made from elements like molybdenum, tungsten, and chromium which can withstand high temperatures without losing its hardness as quickly as high-carbon steel.
There is another type of steel, referred to as M2 steel, which is a particular formulation of HSS designed to be even more resistant to wear, easy to grind, and long-lasting.
Recently, Cryogenic M2 steel has been introduced to bowl gouges as yet an even harder, longer lasting option.
It is believed that the cryogenic steel tempering process conditions the steel altering its properties better than all other processes.
Look along the shank of the bowl gouge or the handle for a mark or a stamp indicating what type of steel was used to make the gouge.
Bowl Gouge Basics – Sizes
Bowl gouges are usually sized by the width of the flute. Some manufacturers, however, use the shaft diameter when labeling their gouge sizes.
Typically, the width of the flute is the stated size of a bowl gouge. So a bowl gouge labeled as a 3/8” gouge usually has a 3/8” wide flute and a wider 1/2” wide shaft.
When ordering bowl gouges, make sure the width of the flute and shaft are clearly defined. If this information is not clear, make sure to clarify the flute width before ordering.
For example, some manufacturers will call a gouge with a 1/2″ wide shank a “1/2″ bowl gouge,” when most others call a 1/2″ wide flute a “1/2″ bowl gouge.”
The length of the bowl gouge shank is not as much of a factor as the width of the cutting tip and flute. Narrower sized shaft gouges are typically a bit shorter than wider gouges, but not by much.
Bowl Gouge Basics – Shapes
There are several different bowl gouge flute shapes. The shape of the flute is created by the shape of the milling tool used to mill out the flute area.
Some bowl gouges, especially older models are made with deep “V” shape, or a deep “U” shaped flute designs. Both of these gouge shapes are generally regarded as less desirable because they can catch or grab easily and don’t provide a smooth even cut.
The most popular bowl gouge flute shape is the parabolic or modified shorter “U” shape that leaves an even thick path of supportive metal at the base of the gouge. Another name for this gouge profile is a “super-flute.”
Most current bowl gouge designs incorporate some version of this Super-Flute design.
Bowl Gouge Basics – Grinds
The bowl gouge manufacturing and design is rather simple, a handle fitted with a steel shaft which has a flute-shaped groove milled along the top edge.
It is up to us, as wood turners to shape the tip of the bowl gouge to fit our specific needs. We need to decide what “grind” to create at the tool’s business end.
What is a bowl gouge grind?
The term “grind” generally means the specific profile, bevel angle and side wings present on a bowl gouge.
There are many different options available for bowl gouge grinds, here are a few of the bowl gouge basics grinds:
- Traditional Grind
- 40/40 Grind
- Fingernail Grind
- Modified Fingernail Grind
- Irish Grind
- Ellsworth Grind
- Micro-Bevel Grind
Bowl Gouge Basic Uses
Remember at the beginning of this article I said you could turn an entire bowl with one bowl gouge? Well, that is very possible, but specific bowl gouge grinds offer different advantages at times.
Each bowl gouge can have a different grind and serve a different purpose. Because of this, we can order, for instance, three identical 1/2” bowl gouges and shape the tips of each different making them each good at a certain specific task or multiple tasks.
Most of the grind profiles shown above can be used for the majority of the time turning a wood bowl.
Each grind has a slightly different bevel angle, and the bevel angle ergonomically affects how you turn the bowl.
To learn more about the bowl gouge bevel angles and how they work, read this article when you finish here.
Short-winged bowl gouge grinds, like the traditional, fingernail and the 40/40 grind, are good general use gouges. These gouges also perform well with punky, loose-grained woods, like spalted pecan.
Longer-winged bowl gouges, like the Irish and Ellsworth grinds, have the added advantage of being able to make scraping and shear-scraping cuts using the cutting wings against the bowl surface.
If you haven’t started shear-scraping with a bowl gouge, please read this article next. You’re going to love the final results.
The micro-bevel steep grind gives this gouge the unique ability to make clean cutting passes deep down inside a tall or narrow vessel.
With the steep cutting angle of the micro-bevel gouge, the tool handle is oriented almost perpendicular to the bowl bottom when the cutting edge engages the wood surface.
Shaping A Bowl Gouge
Not to be mistaken for sharpening, bowl gouge shaping is usually only done once when a bowl gouge is first acquired.
Most manufacturers apply a simple generic edge to the tip of a new bowl gouge. The manufacturer’s tip usually isn’t what you want to start turning with unless you have purchased a specialty gouge which has already been pre-shaped.
It is usually best to decide what grind you’d like to apply to a given bowl gouge and keep that grind for the life of the gouge.
Changing profiles or grinds on a gouge can be time consuming and wasteful, as large amounts of metal is wasted each time the grind profile changes.
Use a protractor and establish the desired bevel angle on the front of the gouge. Next, take advantage of a sharpening jig, which we will discuss more in a moment, to carefully grind the shape of the tooltip and the side wings.
Grinding removes more material than sharpening and goes quicker with a more coarse grit grinding wheel. I have a 180 grit and an 80 grit CBN wheel on my grinder. The 80 grit CBN wheel is used to shape metal.
Continue grinding the bowl gouge tip until the desired grind profile appears.
Sharpening A Bowl Gouge
A good quality sharpening station is needed to sharpen a bowl gouge and a major component of bowl gouge basics.
Yes, bowl gouges can be sharpened by hand, but that is a very tricky and challenging endeavor.
Instead of wasting time and gouge steel sharpening by hand, I recommend using a gouge sharpening jig system.
The sharpening jig is quick, convenient, but most importantly it is consistent.
Follow the sharpening jig steps and gently apply the bevel edge of the gouge to the finer grit sharpening grinder wheel. Make light passes without adding much pressure. Let the wheel do the sharpening.
After a smooth, shiny bevel surface appears around the gouge tip, the tool is sharp and ready for work.
Check out this article to learn more about the details of sharpening a bowl gouge.
How To Use A Bowl Gouge
A bowl gouge slowly removes layers away from a turning wood bowl blank. Each pass removes another layer, one after another.
The lathe tool rest needs to be positioned relatively close to the wood bowl blank to give yourself a leverage advantage with the bowl gouge handle.
Rotate the bowl gouge to the side slightly, so the side of the cutting edge engages the wood. A rotated gouge tip makes a less aggressive and more smooth slicing cut against the wood.
When starting, do not have the flute open, or visible and pointed upward. In this position, the gouge can engage too much wood too quickly and cause a “catch.”
Later, after you are more comfortable with making bevel riding cutting passes, then you can start rotating the tool to an open position. However, the open flute position is ideal for more delicate finishing cuts that only remove thin layers at a time.
An ideal cutting pass involves having the flat bevel surface nearly parallel to the wood surface. When the bevel is flush with the wood, this is known as “riding the bevel.” Here’s an article that covers riding the bevel thoroughly.
When the bowl gouge is not fluidly riding the bevel, tool marks in the form of grooves, scrapes, and ruts will most likely be visible on the bowl surface. Here are some hints for fixing tool marks.
Because of the bevel angle, lowering the gouge handle a bit presents the gouge bevel accurately and make even smooth cuts. Also, with the handle lowered, you have more leverage control over the gouge.
Attempting to make cutting passes that remove too much material at one time can result in a catch. A catch is any sudden incident when the wood blank resists being cut by the gouge.
While catches can occur and are somewhat startling, with experience and practice, you will know when the bowl gouge is reaching its limit and be able to prevent a catch from happening. Read this article to learn all the ins and outs of wood bowl catches.
Four Bowl Gouge Cutting Techniques
There are four main cutting techniques with a bowl gouge, which include; the pull cut, the push cut, the scrape cut, and the shear-scraping cut.
The pull cut is a bevel riding cut, meaning the bevel is flush or parallel with the wood surface. When the tip begins to cut the tool is pulled towards the turner along the bowl surface.
A push cut is also a bevel riding cut and involves pushing the bowl gouge tip forward along the bowl surface to make the cut, just as the name implies.
The next two cuts require longer side bevel wings. The Irish and Ellsworth grinds are ideally suited for our next two cuts.
Unlike the pull and push cuts, the scraping cut does not involve the bevel at all. Instead, the gouge is flipped over with the flute facing the wood surface.
Only the top gouge wing lifts slightly away from the surface. The lower wing is in contact with the wood and does all the scraping action.
The bowl gouge is held nearly horizontal when performing the scraping cut. This cut can quickly remove material and is best used to make adjustments to the shape of a bowl.
Similar to the scrape cut, the shear-scraping cut utilizes the wings of the gouge against the bowl surface.
The tool is oriented in a steep upward angle, almost 45°, and the same lower wing is used to make the shear-scrape. Because of this angle, the engaged scraping gouge wing acts like a razor and gently shaves off wispy thin layers and any high spots.
Shear-scraping requires a bit of practice but is a fantastic way to finish the exterior of a bowl to the point that little to no sanding is necessary.
Shear-scraping is best used on just the bowl exterior. Bowl interiors are a bit tricky with this cutting technique and can result in catches.
Bowl Gouge Basics – Where To Start
When you’re starting, use one or two different gouges of medium diameter, a 1/2” bowl gouge is a good size to start with, and practice until you feel comfortable.
After acquiring some experience, slowly introduce a smaller gouge, like a 3/8” gouge, to create fine, delicate finishing cuts. Also, try a larger 5/8” to 3/4” gouge to act as a wood plow to quickly remove waste material or work larger bowls.
As you progress along your wood bowl turning journey, you will most likely acquire bowl gouges of different shapes, sizes and grind profiles.
Bowl Gouge Conclusion
The bowl gouge is the quintessential tool for any wood bowl turner.
After you’ve spent time turning with a variety of different bowl gouges and developed your bowl gouge basics, you will truly appreciate the wide range of possibilities available from this humble wood bowl turning workhorse.
As Always Happy Turning,