Interlocking Chess/Checker Board Puzzle

Hey everybody!

Do you like board games?  How about wooden puzzles?  Yeah?  Then I have the perfect instructable for you!

This goal of this project was to design a chess board which is composed of several interlocking wooden pieces.  In this case, a picture is worth a thousand words, so please check out the pics to see exactly what I mean.  Then we can get started!

For this project, you will need:

Wood* - 16' of 1.5"x3/4" strips
                  6' of  2.5x3/4" strips

Tools - Miter saw (optional)
              Table saw (mandatory)
              1/8" kerf table saw blade with lots of teeth (better for making lots of fine cuts)
              3/4" dado blade for table saw (optional, but definitely recommended!)
              T-square or some type of ruler (digital calipers are nice to have, but optional)
              Power Drill/screwdriver

Other Materials:
             (2) Hinges
             (2) Latches
             (8) 2" screws
             Dark stain (I like MinWax's Gunstock, but it's up to you!)
             Varnish (I wouldn't recommend varnish, but it does make things shiny....)
             Chess pieces!  Buy them online or make them with a scroll saw

*Note: Be careful about selecting wood that is straight. Warped wood will cause problems later on. It's also tempting to use exotic hardwoods for their contrasting colors, but I highly recommend trying this project with cheap pine first before you spend $$$ on nice wood.

All of the pieces for the board have been drafted using Google Sketchup 8.0.  I like the program a lot, since it's intuitive and available online for free!

If you have any questions, please let me know.  I have individual sketchup files for each of the pieces and a powerpoint with the blueprints if the resolution on the pictures is not good enough.  I can't figure out how to upload those files, so just let me know if you need them.

In general, you're just making a bunch of 1.5" squares connected by 3/4x3/8" strips.  Also note the part designations (A, B, C, etc.), because we'll be using those later for assembly.

Once you have the blueprints, you can probably get started in the shop.  But here are a few helpful hints that I've learned from making these boards:

1.)  I like to cut the blanks first with the miter saw and make sure they're all even.  I also cut one extra blank for parts A, B, C, D, and E, since I inevitably make a mistake on one of them!

2.)  Know the the flaws of your saws and plan accordingly.  Since I'm a grad student, I have the cheapest table saw Craftsman has to offer.  After much frustration, I know that it likes to break chips off of wood to the left of the blade (see pic) and the blade is always about 1 degree off perpendicular to the table. 

3.)  Since you'll be sawing away 50% of the wood, a dado blade is a very nice thing to have.  It makes things go much quicker.  You can still use a regular 1/8" blade though. 

4.)  I typically set the blade to 3/8" high and cut all the board pieces(A-E) at once since they all have similar dimensions, then I cut the box pieces (F-H).

5.)  I get much better results if I make all the A's at once, then the B's, etc. to make them as indentical/interchangeable as possible.  Also note that A, B, and C are essentially the same parts, but with small differences, so they're good to make together.  Same thing for D and E.

6.)  I find it's better to cut the squares first, since they're the most important part.  That way, you can start over on a piece if you mess something up.

7.) Test fit the pieces as much as possible.  Make sure the gaps between squares are 1.5" apart with a scrap strip of wood and check that the pieces fit together well as soon as you get that far.  It may be necessary to shave off an additional 1/16" from the dimensions to make the pieces fit together easily.

8.)  Make the board first and assemble it (see next steps), then make the box.  That way you can account for any deviations in size when you're making the box. 

9.)  Fitting the pieces together should go very easily, with little force applied.  Do not use hammers!  Hammers tend to break the pieces (See pic!)  But even if a piece breaks, wood glue can salvage it. 

10.)  To err is human.  If you fit the pieces together and there are some noticeable gaps, don't give up!  I've made this project twice now and I'm convinced it's impossible to pull off without imperfections.  Besides, once you put on a little dark stain those imperfections will be much much less noticeable!

Before you start sanding and staining, make sure that everything fits together alright.  Try to assemble the board and the box all the way.  There are more details on the board assembly later on in the instructable, but I've included some photo hints on this page to help.  That way you can tweak things while the saw is still hot!

Try to make sure the pieces are identical as possible, so it makes for a good puzzle with more than one solution.

Once again, everything should fit together without much force.  If it doesn't slide into place, you should consider shaving a little off the necessary dimensions.  The box pieces should fit pretty tight though, since they're a lot thicker and stronger.

Note:  This step is a true test of my patience.  But if you take your time, I assure you it'll feel great when the last pieces slide into place!

So everything fits together now, right?  Awesome!  Great job!

I like to first assemble and organize all of the pieces so I can easily keep track of what I need to do.  For sanding, I start with 80 grit to get out big scratches, then finish off with 120 or 160 grit.  I only sand the top and bottom of each board piece, since they'll be the only exposed parts.  Finally, please be sure to use a dust mask to protect yourself.

If you used naturally dark and light woods, you'll probably only but a coat of oil or varnish on the wood after sanding.  But if you use pine like me, you'll want to stain the pieces.  Like I said earlier, my favorite dark stain is MinWax Gunstock.  I apply one coat to the long board pieces (for the black squares) and leave the short pieces unstained (white squares).  I also stain the box pieces dark, but you can leave it light if you want to preserve the grain of the wood more.

Now for the fun part!  You can try to solve the puzzle yourself (good luck!) or use the instructions below.  The instructions correspond to the order of the pictures.  I've also embedded a video to help you along:

 

1.)  Organize the pieces

2.)  Get pieces for one half of the board - 1 A, 2 B's, 1 C, 4 D's, 4 E's, 1 F, 2 G's, and 1 H.

3.)  Slide the 4 Part D's onto a Part B.  The short stub should face the Part C.

4.)  Slide the 4 Part E's onto the other Part B, with the longer stub facing the Part A.

5&6.)  Hold the B/D/E parts at a 45 degree angle and slide them together.

7.)  Let the pieces fall flush with one another.  DO NOT use excessive force for this step.

8&9.) Slide Part C in from the right side.

10&11) Slide Part A in from the left side. 

12&13.)  Fit the left side of the board into the groove on Part H

14&15.)  Slide the Part G's onto the sides of the board

16-18.)  Slide Part F into place on the front

19&20)  Repeat these steps for the other half of the board and viola!  Chess board!  Also
check to make sure everything is flush when the board is folded in half.  

Looks great, feels great, eh?  :-)




 

What you do with the board from here on out is up to you.  If you wanna leave it in pieces, that's cool.  I chose to add some hardware to the board for regular use.  No matter how hard I thought about it, I couldn't avoid using some kind of hinges and latches to keep the board together.  I've seen wooden hinges, but I do like the bling that gold hinges bring to a project (lol).  Please share any ideas you might have....

To install the hinges, put the two Part F's together flush first such that the teeth on the top part are in contact.  I find that using clamps makes this step a lot easier.

Install the latches by matching up the Part H's as shown in the picture.  Every latch is different, but make sure they hold tight.

Finally, if you want to, you can solidify the box with some 2" screws in each corner.  It makes the board a whole lot more stable for gameplay and you can always take them out later if you want to.

Note:  Make sure to predrill your holes and tighten screws with a screwdriver to avoid splitting the wood.

Congratulations!

If you've gotten this far, then you've definitely proved your woodworking skills.....and your patience.  Good job!

Before you start playing, though, you're gonna need pieces.  Checkers are the easiest to make, just use a 1 1/2" hole saw on a drill press to cut circles out of scrap wood and stain them. 

Chess pieces, on the other hand, require a little more work.  Fortunately, I happened to have some nice marble pieces laying around to use.  Otherwise, you can always make your own.  There are some good free plans available online if you google compound cut chess pieces.  Or you can just freestyle it.....either way, please post pics of your boards!  I'd love to see them.  Have fun!

Finally, please let me know if you have any questions.  I will be more than happy to help.

Plans for chess pieces from Steve Good:  http://www.stevedgood.com/chessset.pdf