Can't answer your question. By my understanding, typical interlocking shelves are bad design, because they can lack support at the front and back of the shelves. In your case that may still exist, but may be lessened by the inset dados in the support. How has it held up for you?
I did some work on an old motel and when we removed the bed,
the frame was interlocking boards just like those in the vertical position
and the joints look almost identical.
so that profile may not be limited to just shelves.
A lap joint is when the two pieces completely cross eachother, such as in a cross. A half lap is when the 2 pieces are joined at an end such as a picture frame corner or a cabinet face frame corner.
The same exact principle, just a hatter of where the junction takes place.
Tony BRetired woodworker, among other things.
"Strive for excellence and settle for completion" Tony B
Looking at your post again I see the dados on the supports, that is an interesting twist.
The diagrams on the sawdustmaking website looked familiar, and they did cite the source too. Sure enough, they came from a very good woodworking book that is in the public domain:
Woodwork Joints: How They Are Set Out, How Made and Where Used, by William Fairham.
I found it I was looking for woodworking books on the Gutenberg Project. It would not seem out of place today. We still use the same woodworking joinery. Here is a link to the book: https://www.gutenberg.org/ebooks/21531
The Gutenberg Project is a website with many books and other writings, all of them in the public domain, free for anyone to read, download, reprint, and use. Here is a search for free woodworking books on Project Gutenberg. See if you find anything you like: https://www.gutenberg.org/ebooks/sea...ry=woodworking
By definition, a bridle joint has lap joint features along with mortise features. I'm not a professional woodworker as I have never nor will I ever sell any of my work, so take my humble opinion as that of a serious amature. I was a self taught hacker until my retirement in 2009 - I now consider myself to be a self taught craftsman!
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