The Kumiko lamp is finally finished. It took the longest time to wait for the arrival of the power cable, light and light socket (e14). I like it so much that I will probably make it again for myself, haha.
If I understand correctly, you mean the joints where the horizontal oak bars meet the vertical leg?
On another lamp I tried simple butt joints, but those were too imprecise. The other lamp sort of became diamond shaped instead of square shaped when looking at it from the top. Also, butt joints would have caused this lamp to fall apart, because the kumiko frames where a little bit too large for places where they are now press fitted in.
On this lamp I support these butt joints with regular round dowels. This allows me to exactly measure where a horizontal bar would be needed to be placed to fit the kumiko frame. Any error during drilling would of course ruin the whole thing. Due to the oak bars only measuring 12mm in width, the dowels could only be inserted about 8mm deep for one horizontal bar and about 4mm for the other perpendicular bar.
As for how the kumiko frames are attached to the lamp frame: slide in and glued.
Nice, yes that was what I was looking for. Dowels do sound a lot easier to deal with than a custom joint, especially for a newbie to woodworking and joinery like myself. I sort of made a mortise and tenon joint with the vertical leg and one horizontal leg, and then cut half of the mortise (leaving just the upper half), and made another mortise and tenon joint for the other horizontal leg, cutting half of the mortiose (leaving just the bottom half), trying to get those to fit in nicely. I think it could work but one imperfection and I need to dimension more wood. I guess difficult things are difficult to do.
Dowels huh? Now you have me thinking. Again, great project, it looks really nice!
You’re welcome and thank you! Yes, I also tried similar joints on one lamp. It turned out that I am too impatient and imprecise to create such joints by hand. Dowels seem much easier and achieve about the same thing. The angle doesn’t matter in this case as there aren’t large forces involved, so (1) initial hand adjustment and glue should suffice and (2) the Kumiko frames will push the the connecting bars in the right angle anyways.