Monday, January 21, 2013

Diagonal Chinese Cross - BTK Project with VIDEO

An alternative title is:

Fun With Drywall Screws

This was a really fun project.

Not long ago I listed a few of my favorite woodworking books.  In this list was this one:

Fantastic book on Joine
Ever since I read this book I couldn't wait to try some of the wooden puzzles listed in the back.

  • Music:  Jig of Slurs. Dublin Reel - Merry Blacksmith. The Mountain Road (Sláinte) / CC BY-SA 3.0

This was a brilliant project, that reinforces some basic fundamental skills such as squaring stock super-accurately, paring with a chisel, and layout by eye.

The book says you should use a stick of wood 1/2" square and cut it to 2 1/8" long pieces.  I wasn't sure how this was going to work, so I went through the trouble of sawing some 3/4" stock down to 1/2" to make sure it would turn out.

As you'll see in the video, you can't really measure the angle, so you are welcome to make this puzzle any size you want.  The pieces should be at least 1/2" longer than twice the diagonal of the endgrain  (watch the video, and you'll understand what I mean and why).

I found it helpful to use drywall screws to secure a few bits of scrap onto my bench hook.  This facilitates holding the small pieces so you can work on the diagonals.

Please be aware, there are a lot of ways to seriously injure yourself while doing this project.  It only takes a small toolkit (jack plane, marking gauge, crosscut saw, and a large-ish chisel - 3/4" or so), but with these small pieces you might be tempted to secure them with your hands.  Please do not let any body part get in front of the leading edge of your chisel.

Moving on, the first one I did in walnut turned out well.  I just put some wax on the pieces for a finish.  Fairham leaves you to figure out the solution to put it together yourself, which took me about a half hour.  I got the impression that it was a bit loose and sloppy, as as soon as I touched it the darned thing fell apart again.

The second one (this time in cherry finished with boiled linseed oil) I chose to leave all of my cuts well inside the lines, hoping that it would cinch up tight.  WRONG!

This made it even sloppier and looser, to the point that it wouldn't go together.  I opened the joints up a bit, and it held together, but about like the first one.  I did find out that once it is together, if you press all of the pieces together, then it stays fairly tight.  Perhaps this is the way it is supposed to be.

Perhaps one of you knows the intricacies of the construction of this puzzle?  In the meantime, I think I'll leave these on my desk and watch the faces of my visitors as the puzzle disintegrates as soon as they touch it.

1 comment:

  1. Fairham wrote a few more books on woodworking that you might like also. This one is very good and I'll have to look up how to assemble/disassemble your puzzle.