In the first article of this two-part series, I showed you how to take a piece of fresh timber and machine it into a blank ready for turning. Now we can continue with the process to produce a wonderfully finished bowl, graced with a certain elegance that can only come from natural wood grain. I will show how complete your bowl with various lathe attachment options, and how to dry it to avoid too much warping or cracking. So, dust off that lathe, and let’s get turning!
Preparing the blanks for turning
Natural edge
Mounting the blanks onto the lathe is slightly different between natural edge and standard bowls. For a natural edge, I tend to create a flat on the natural edge face with a Forstner bit. This flat should be big enough to take a large four prong drive. Give the drive a couple of good taps into the blank, using the drill point as a centre. The blank is held between the two centres using a tailstock ring centre for extra security. The bowl can now be turned to shape, leaving a foot as a hold point for the chuck. This foot can be removed later, when finishing the bowl after drying. When happy with the outside shape, reverse the foot and remove the inside, leaving the bowl about 20mm thick.
Standard bowl
Preparing the blank for the standard bowl is a little simpler. Here I’m using a faceplate in the conventional way (see below). Again, turn the outside of the bowl, leaving a foot as a hold method for the chuck. This time the top of the bowl has a flat face as opposed to the natural edge. Once the outside is shaped, reverse the bowl and remove the centre.
Workshop preparation
When preparing for a session of wet turning, there are a few things to consider. You will make an huge quantities of shavings! These shavings will be very wet, and the sap will spray away from the lathe. Of course, moisture causes rust and staining. Cover as much of the workshop with tarpaulins or dust sheets, and protect any bare metal surfaces from the moisture. If you leave the job over night, make sure you wipe down, oil or wax your tools, chucks and the bed of the lathe bed to avoid corrosion. Tannic acid is a natural acid found in oak, chestnut, olive (Olea europaea), yew (Taxus baccata), etc. As you can see from the picture (below middle), this acid will cause your tools and hands to go blue, and in some cases, cause cracking of the skin. Using a barrier cream on your hands is a wise choice if you have a lot to do. You can also use camellia oil or wax to protect the lathe and tools.
Drying your bowls
How to
I tend to do all the backs of the bowls first. I then reverse them to de-core, leaving them around 20mm thick. As they dry and distort, there should be enough thickness to re-turn the bowl to shape. However, the bigger the bowls become, the thicker you’ll need to leave them. While turning all the backs, I keep the unfinished bowls buried in the damp shavings until they’ve been de-cored. Once turned, I tend to keep them in the open air to dry.
Top tip
Don’t stack the bowls, otherwise they will grip onto each other, causing stress to build up and possible splitting.
Either stand them on their sides or put sticks between them, keeping them apart. If you are rough turning in the summer months, it is wise to dry your bowl in a bag of dry shavings, turning them regularly and getting them back out in the autumn to finish drying.
Drying time
Drying time normally takes around six months to a year, depending on the timber and time of year but the slower you can make this, the better result you will get.
Finishing off rough turned bowls
Now to start finishing some of the rough turned bowls from last year. See in this picture (above) how I’ve altered the wall thickness depending on the diameter. This is to carry the extra movement of larger pieces. A word of caution: remember that your bowls have moved and are out of balance, so keep the lathe at a low speed to true up. Always turn the piece by hand before you start the lathe, making sure that no part of the bowl will meet the toolrest.
Holding a bowl on the lathe
The first thing we need to decide is a holding method for our bowls. This will depend on the chuck you own. I’m using a medium size set of Gripper-type jaws to hold a wooden drive dome. The drive dome is made from a piece of scrap timber and roughly shaped. This will sit inside the rough turned bowl and act as a friction drive when pressure is added from the tailstock. If the bowl is too large for a dome, then a large bowl blank can be used. This way you won’t be wasting any wood as you can use the bowl blank when you’ve finished rough turning.
Firstly, I’m going to clean up the foot of this small Claro walnut (Juglans hindsi) piece. The foot will eventually be re-shaped, but it remains important at this stage, and is needed to form a good hold point for shaping the inside of the bowl later. When the foot has been trued up, you can continue to cleanly cut the outside profile. Sand and finish with your chosen polish or oil.
Turning the inside and finishing the bowl
When the outside is complete, turn the bowl around – this time holding the foot in your chuck. True up the rim of the bowl before starting to hollow out the remaining timber. It’s important that you reduce the wall thickness of the bowl by a small section at a time to avoid chatter. In these pictures, I’m cutting down about 50mm into the bowl, getting the wall thickness where I want it to be before progressing any deeper. Continue with this method until you have taken out the uneven waste timber and you have the desired thickness. Finish by sanding and polishing. To finish the bowl, I’ve used a set of button jaws to hold the rim and have cleaned up the foot, creating a small cove and slight recess on its bottom.
Summary
After 6 months of preparing, machining, drying and finishing, you will have a beautiful bowl that has a story to tell. Rough wood turning has many benefits. Its reduced cost is just one of the many reasons why I believe it is a great choice for those making their first forays into woodturning. It also teaches you about the properties of wood – specifically, the effects moisture differentiation, and how to mitigate these changes throughout the process. With patience, diligent machining, and good storing techniques, we see how splitting can be avoided – knowledge that will be of benefit in other disciplines of woodwork.