What is a hollow form? It’s a form that has been hollowed usually through a small hole at the top. Although sometimes the hollowing is done through a larger hole at the bottom and plugged giving the illusion that the hollowing was done through a tiny hole left at the top. Other times the form is split, both halves hollowed Then glued back together again giving the illusion of being done through a small hole. Another method is to split the piece into two or more pieces, rotate those pieces, reassemble and turn the outside. After turning rotate the pieces back to the original configuration and glue together. This is called inside out turning. See my ash piece with bark in this gallery.
Most times these forms are art pieces to display unique beautiful wood. Other times they are used as cremation urns. Occasionally they are used as vases for dried flowers. I particularly like to use lumps of wood that have knots, bark inclusions and interesting weathering or grain patterns.
Hollowing is a tedious process especially if you are working through a small hole. You have to stop frequently and blow out the chips as they accumulate inside. This is alleviated somewhat if the piece has a hole of some kind in the side that allows the chips to fly out as it is being hollowed.
Doing the hollowing is basically working in the blind since most times it is impossible to see the tool. Various tools have been made to make it easier to judge how thick the piece is. The most popular one is a laser pointer fixed outside the work piece that shines on the end of the tool. Thus when the tool is inside the hollow form the laser dot shows its location on the outside of the form allowing you to judge the wall thickness. Of course if there are holes in the side judging thickness becomes a lot easier. At some point I may do a photo essay on the process.
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