Kuruma Kikkō

 

For some time now I’ve been wanting to make a kumiko pattern on a larger scale.  I’ve been playing around with a lot of different patterns making small sample pieces, but I kept thinking that it would be nice to do something big.   Then a couple of months back I found myself in a building that had some really interesting wall paper that was almost identical to a kumiko pattern called chōchin masu-tsugi.   Seeing that pattern spread out over a large wall was really intriguing because as the pattern becomes part of a larger field certain shapes and forms visually come to the surface.  It piqued my interest enough to take a shot at the chōchin masu-tsugi pattern, so I made small sample:

 

 

When you see this pattern from afar and when it’s spread out over a large area the shapes become softer and the octagons start to look like circles all within a grid of squares.  It’s a pretty cool pattern.

But there is another pattern, called kuruma kikkō, that I like even more.  It’s very similar to the above pattern except instead squares, the pattern is based on a triangular grid, and the circular shapes are even more pronounced.

Here is what the kuruma kikkō pattern looks like:

 

This is the pattern that I’ve decided to attempt on a larger scale, and the project is a room divider/folding screen composed of three panels that are filled with these shapes.  The panels are each about 18″ x 54″ and include a lot of pattern pieces so I’ve been experimenting with some new methods to speed up the process a bit and thought I’d share the results.  I won’t go into every detail regarding how to make this pattern, but if you’re interested to make it yourself I highly recommend Des King’s kumiko books, which explain all the necessary steps in great depth.

 

I’m using two different thicknesses for my kumiko.  The thicker pieces are about 4mm and the thinner pattern pieces are about 2.5mm, and all the material I’m using is basswood.  I really like basswood for kumiko.  It’s really nice to work with, hand planes to a nice shine, and it’s inexpensive.  It’s also pretty soft which makes it a forgiving wood for kumiko work, since it can take some compression if some of the joints or pattern pieces get cut on the tight side.

Here I’m in the process of making kumiko, planing the strips with Japanese hand planes to the final thickness.

 

And here is just part of the stack of strips need for all three screens.  I attempted to calculate how many strips I would need for one 18 x 54″ panel and it turns out I made just enough of the thicker strips for the grid, but not nearly enough for the pattern pieces.  So I’ll definitely be making more soon enough.

 

Next I started to layout and cut the 4mm pieces to form the jigumi, or triangular grid-work, that will hold the kuruma kikkō pattern pieces.

Here I’m clearing out the notches after cutting the stack at 60 degrees.

 

And here is the same stack realigned to make even more cuts that will mate with the kuruma kikkō pattern pieces.

 

Here are same pieces but with the completed half-lap joints cut to fit the pattern pieces.

 

And this is the stack of completed jigumi parts, needed for one of the 18″ x 54″ panels.

 

With the pieces assembled you can see how the triangular grid comes together as well as the half-lap joints for the pattern pieces.

 

Now for the tedious but fun part.  There are essentially only two different pieces that need to be made to form the kuruma kikkō pattern.  The trickiest parts are the ones that fit into the half-lap joints in the triangular grid above.  Each piece has to have it’s own half-lap to mate with the grid, but that half lap has to be perfectly centered.  So I came up with a little shooting board jig that has a key that mates with the half-lap joint.  With this jig I can “roughly” cut a whole bunch of pieces with a half-lap in the middle and then trim them to size using a plane.

 

It’s not a perfect system, but it works pretty well, and I’m able to mass produce the parts in small batches.

 

The next step for these parts is to cut a notch out of each end shaped at a 60 degree angle that will house triangular pattern pieces.  The best way that I’ve learned to make these cuts is by using another jig and a marking or cutting gauge.   I learned about this method from Des King’s kumiko books.  In fact I’ve learned most of what I know about kumiko work from his books, they are great resources!

This jig is called a jaguchi jig and it’s pretty simple in design.   Basically it involves two stops/fences to butt the pattern pieces up against, and an angle cut on the end (in this case 30 degrees) so that a marking gauge can be used to make a 30 degree cut into the end of the pattern piece.  To use it, set the pattern pieces up against the end stop and set your marking gauge so that it just starts cutting at the very corner of the piece.  Then you take several passes cutting with the marking gauge and stop once you are half-way through the thickness of the piece.  Then flip the pieces over and repeat.  If you’ve cut cleanly the waste should fall out and you will have a nice 60 degree cut on the end of your piece.

Here I’m cutting a row of 6 pieces and using a piece of ply to hold them steady while I cut the angle on all of them at once.

 

And here are the completed pieces with cute little triangular cuts on the ends.

 

That’s about it for now.

There is a lot more to discuss and a lot more pictures detailing the process and the various jigs I’ve been using, but I think I’ll save that all for another post.

Stay tuned…. but in the meantime here are a few shots of the first panel, nearly complete.