Trunnel, also trenail, trennel, or treenail.
Trunnel, looks simple and small, but it's a very important part of the boat, A treenail is a wooden peg or dowel which can be used to fasten pieces of wood together, it is a traditional method, usually a well seasoned treenail is driven into a hole, when it takes up water, it will expand and 'grip' its position. Simple but quite effective fastening of old. It was considered suitable use in the Grayhound project and would be used to join frames together, and planks to the deck and the hull. It was deeded a variable method against metal fastening due to their increasing cost and the use of oak that was a waste product to make the treenails. There will be 4000 more trunnels to be used in building up the boat.
people used to use the oak stick to cut out the trunnel. There are a few machines to produce the trunnel. The most modern way is the dowel cutter. Before the dowel cutter, trunnel was a job for kids and women. Because they just need to use a hammer to hammer the wood through the circualr mold. The dowel cutter is hard to use, you need to hold is hard when is cutting the wood, or the inertia will move the wood away.
Treenails it's a hard challenge for wood skill.
http://www.boat-building.org/learn-skills/index.php/en/wood/treenails/
Wonder about use of wooden nails, in construction of junks in China.
ReplyDeleteMaybe of interest —
On Deck With China’s Last Junk Builders, Masters of an Ebbing Craft
点击查看本文中文版
Didi Kirsten Tatlow
The New York Times, February 2, 2017