|Project by David LaBolle||posted 03-02-2011 12:31 PM||11033 views||23 times favorited||30 comments|
Here are a few variations I have done of double twisted dovetails.
The first pic shows the joint as it is sliding together. Neither board can slide in or pull out as one of them would with normal dovetails. Therefor the terms “pins” and “tails” or “socket” doesn’t really apply with double twisted dovetails, even though many choose when laying them out to use only a few thin “fingers” for the joint which then appear to be “pins.” To put it together you slide them together at about a 45 degree angle, or rather, they slide down along the plane of the angle used.
For anyone wanting to give this joint a try, I have no secrets to keep and am happy to share. To lay it out all I need is a sliding t-square set tightly at a moderate angle, a good sharp marking knife, a comfortable place to sit, and a bit of quiet time. Make sure the t-square won’t slip or change angle as you will use that t-square many times per joint. I don’t use math to set it to a magic angle. I have no idea if my square was set to 7, 8, or 9 degrees. I just do it by eye. As far as the width of the pins or spacing between them, again I do it by eye. Look carefully and you should be able to figure out how the angles intersect from the face of the joint on across the top. Again, I use the same t-square set at the same angle all the way. The hardest part is transferring the angle from one board to another. To transfer the lines from one board to another I place them face-to-face and use my sliding t-square t scribe a mirror image of the first board. Look at the second pic carefully to see how they were placed when transferring from one board to another. It’s not so much “hard” as very exacting. The whole joint is really. You must use the sliding t-square to lay the lines at a precisely consistent angle. The cutting, as well, must be spot on. I have not found any way to fudge or repair a mis-cut line. If you lay out every line consistently and cut them each precisely the joint will work.
The box has the same profile showing of the dovetails on all four sides and appears to be impossible to assemble. It’s not impossible of course. I’ll shoot a short video next time and post it on YouTube for anyone interested.
-- When we build, let us think that we build forever. Let it not be for present delight nor for present use alone. Let it be such work as our descendants will thank us for