RoboHippy shares some valuable insights on Bowl Blank Prep and using Chainsaws safely and effectively. Bowls for food use: In Europe, many wood utensils, like bowls, spoons, platters, salt and pepper shakers, tub butter holders and the like are used everyday and the wood is intentionally unfinished Bowls for food use, however, can benefit from a few light protective coatings using vegetable oils, (canola, olive, peanut), linseed oil or bees wax applied with a brush or cloth.
I just smile because I happen to live in the most diversified forest in the world; Camphor wood from China, Cork Oak from Portugal, Carob originally from the Middle East and known for its seeds as a chocolate substitute, Siberian Elm from Siberia, as well as all of the Pines, Magnolias, Sycamores, Oaks, Ashes, Maples, Fruit trees, and on and on and on that are familiar to my wood turning brethren on the east coast.
The bowls are weighed to the nearest gram every few days, and are returned to the floor until the weight loss is less than 2%. The bowls and bags are then placed on a table or shelf off the concrete floor until the loss between weighings is again less than 2%. At that time the bowls are removed from the bags, and when the bowls are no longer losing weight they are dry enough to sand and receive finish.
I have dabbled in it for years, following the work of Robin Wood in the UK and Roger Abrahamson here in the US. But for Greenwood Fest, we’ve got someone who really knows it. We are excited to have a great bowl turner from England, Owen Thomas, come join us. Owen & I not yet met, but have several mutual friends and I’ve been watching Owen’s work on the web for quite a while.
A fastening recess has to be turned or drilled into the bottom of the blank before it can be mounted on the chuck The softness of green wood makes it susceptible to crushing when the jaws are expanded. Obviously there are tons of variables ranging from species to moisture content of the wood when rough turned to the size and wall thickness of your turnings. So don’t get frustrated — I’ve broken (and continue to break) my fair share of bowls at one point or another in the process. Unique types of grain, such as crotch wood, ripple, burrs, burls and spalting are explained, showing how these phenomenon are produced and how best to harvest and use them in a turning.
Larger, thicker bowls need to soak longer to ensure good penetration of the alcohol. The way to achieve a symmetrical rounded center is to start at the left of the wood with the side to side cut and continue sweeping gently toward the right side of the bowl. One of the problems you must overcome when replacing paper bags is the alternative material must allow the moisture vapor to freely pass through the material, to allow the wood to dry. There’s an infinite amount of shapes and sizes to raw wood stock suitable for bowls. Some bowls have a delicate nature or pierced side and are best admired on a shelf.
The reason bowls turned to this thickness (1/4 -1/2)do not crack is simply that most of the mass is gone. I’ve used tung oil pretty successfully as an anti cracking agent on wet wood – very low penetration but just enough to stop the moisture from rushing out. The common explanation is that minerals dissolved in ground water are taken up by the tree’s roots, and the minerals left in the wood. This is important, as a natural-edge bowl is typically made from the blemish- and crack-prone stock you’d normally trim away from most turning blanks. As green wood is turned, the internal stresses of the wood are released without the usual cracking and checking.
The smaller the values and the less difference between them, the more stable the wood. I see many right-handed turners struggling with some cuts, trying to get a smooth surface, and at the same time, covering themselves with wood shavings. This procedure generally precludes the possibility of turning natural edge bowls with the bark attached. It’s also very difficult to buy dry or seasoned wood commercially over 3″ thick.
While there are advantages to carving with green wood, the disadvantage or Cons: are the potential of cracking and checking after carving unless you take precautions which we’ll now address. Greenwood Bowl Mill located near Shreve, Ohio, makes handcrafted wooden bowls which are lathe turned from a single piece of..local hardwood. Once the bowl is roughed out, it can be set aside to dry, then re-chucked later for finish turning. When you receive your wood turning bowl blank, you can rough turn your item to speed the drying process. Keeping the wood wet while turning is essential to stop the wood from drying and changing shape.
In this video, Southern California wood turner Howard Lewin gets you started in the process of turning a bowl from green wood by demonstrating how to cut a log into turning blanks with a chainsaw and a bandsaw. The linseed oil component warms the wood beautifully, and the alkyd varnish component provides water and stain protection. You will also learn about turning bowls out of green (freshly cut) wood and dry wood.
To dry them, I will wrap the outside of the bowls with a layer or two of newspaper, secure it to the rim with some 6 inch stretch plastic film (like you wrap around boxes on a pallet), and cut out the paper on the inside of the bowl. With a little bit of ingenuity the amount of alcohol required to process large bowls can be held to a reasonable quantity.
This keeps the actual distance the tool advances during the transit of the void to a minimum so that no sudden heavy cuts are encountered when the tool makes contact with the wood on the trailing side of the void. Professional turners creating large, perfectly round bowls with a smooth, mirror polished finish first rough turn the shape green, leaving plenty of extra thickness to allow for warping, wait for a year (or more) for the piece to dry out entirely, then finish by turning the final shape and dimensions once the wood is completely dry.