Brian Kent
04-24-2012, 2:15 AM
I posted tonight on the Boat Building forum about a trip to the Great Tall Ship Build "San Salvador" in San Diego. Bruce Heyman gave us far more information than I can digest.
The ship is mostly held together by "trunnels" or "tree nails". I don't remember the main wood for these pegs, but it may have been locust. They use Southern Live Oak for the a lot of the ship's structure, at about 35% moisture. The trunnels are about 5% moisture, of a wood that expends a lot with moisture. They cut a slot, hammer in the trunnel, then use a purple heart wedge. As the Live Oak dries, is both squeezes the trunnel and puts moisture into the trunnel. In the water, the trunnel will expand more, giving a very tight fit.
My question:
I am making an outdoor bench of White Oak, using mortise and tenon, Titebond III, and stainless steel screws to hold her together. As I looked at these trunnels, I thought the wedged pegs might also look very nice. The stainless steel screws would all be hidden, but I would make the wedged pegs visible. If I were to do this, what wood should I use for the pegs (or trunnels)? I would want strength, and a tasteful contrast with the white oak. Instead of using moisture to hold the peg tight, I would use Titebond III and the wedge to hold it tight. The whole bench will be finished with Epiphanes varnish - a couple of coats on the bottom and seven coats on the top.
Thanks.
Brian
The ship is mostly held together by "trunnels" or "tree nails". I don't remember the main wood for these pegs, but it may have been locust. They use Southern Live Oak for the a lot of the ship's structure, at about 35% moisture. The trunnels are about 5% moisture, of a wood that expends a lot with moisture. They cut a slot, hammer in the trunnel, then use a purple heart wedge. As the Live Oak dries, is both squeezes the trunnel and puts moisture into the trunnel. In the water, the trunnel will expand more, giving a very tight fit.
My question:
I am making an outdoor bench of White Oak, using mortise and tenon, Titebond III, and stainless steel screws to hold her together. As I looked at these trunnels, I thought the wedged pegs might also look very nice. The stainless steel screws would all be hidden, but I would make the wedged pegs visible. If I were to do this, what wood should I use for the pegs (or trunnels)? I would want strength, and a tasteful contrast with the white oak. Instead of using moisture to hold the peg tight, I would use Titebond III and the wedge to hold it tight. The whole bench will be finished with Epiphanes varnish - a couple of coats on the bottom and seven coats on the top.
Thanks.
Brian