Make a Pen-Holder Puzzle
Wood can do some wonderful things, and one of them is compress. Use hot water to create this trick pen holder; I bet few of your friends will be able to figure out how it was put together.
Handcrafted presents should intrigue people by their quality of workmanship and by their uniqueness. This puzzle pen-holder is the perfect example of an intriguing present, and can be made to please both young and old. If you have several holders to make, plan ahead so you can cut and work with multiple pieces in a single machine set-up efficiently.
Added Safety
In order to have a flat surface to work on, temporarily mount a piece of hardboard on the surface of your table saw while cutting the small pieces. It acts like a zero-clearance insert.
Clean Up the Machine Marks
With a sharp chisel remove any machining marks left around the pins.
Water and Wood Do Mix
The fibres of the wood soften as they are saturated with the hot water. Notice the pin ends are not mitred in this photo. When Mak made his first pen-holder, pictured here, he mitred the pins after adding the bolt. With subsequent projects he found that mitring all the parts first, then compressing the mitred pin was much easier.
Hardwood is Hard to Work With
Backup strips may be clamped to the board to reduce breakage while you compress the pin. Softwood is easier to compress than hardwood, but a little practice will go a long way.
 Don’t Forget the Bolt!
These pins are fairly narrow and are on the delicate side. Wider pins are less likely to crack when they’re drilled out. The clear tape was used to protect the bolt from moisture, as it may cause the bolt to rust.
Preparing the Pieces
For one octagonal pen-holder, you’ll need eight 1/4″ x 1-1/4″ x 3-3/4″ pieces for the sides and one 1/4″ x 3-1/2″ x 3-1/2″ work piece for the bottom. Before I cut the pieces out from a work piece, I matched the grain pattern and numbered them in proper order. I used walnut found in my scrap bin, but you can use any wood of your choice or even mix woods for a contrasting look. In the next step, I cut bevels on all the sides with the blade on the table saw set to 22.5° for an octagon. Make sure that you flip the pieces properly when you cut the bevel on the opposite edge.
When working with small pieces, I prefer to have a zero clearance insert on my table saw. If your blade tilts towards the rip fence, ensure that the fence and the blade are properly aligned and exercise extra caution when cutting the bevels.
Making the Puzzle Piece
The puzzle piece consists of a number of pins, through two or three of which a bolt is fed. Design your piece with the desired number of pins on it then cut them out. The pins on this holder are quite delicate. Cut them thicker if you want to avoid some frustration. I cut the pins on the table saw using a cross-cut sled, but they can also be cut on the router table, or a bandsaw. Done in a quieter way, you can use a fret saw and chisels. In fact, the whole project can be completed using hand tools alone if you’re a handtool aficionado.
Here’s the trick to getting that bolt through the pins (you’ll get asked about this a lot!):
Immerse the top pin in boiling water for about five minutes to soften the wood fibres. Exercise caution when using the stove.
Take out the piece and gradually compress the pin while still wet in a vise down to about half its length. Let it dry in the vise for half an hour or so. Softwood is easier to compress because it is less prone to break. Practise the compression technique with scrap hardwood first or choose a softwood as an accent puzzle piece.
Drill a hole large enough for the bolt through the middle pins and feed the bolt into the pins. I used a 1/8″ dia. brad point bit so it wouldn’t wander.
Repeat step 1 to return the pin to its original shape and let it dry completely.
Assembling the Body
The mitred pin will likely expand back to its original size, but if it doesn’t you might have to use some hand tools to make some slight adjustments. Using masking tape and rubber bands as clamps, glue up all the side pieces with glue and let it cure. You may need to flush the bottom of the holder with some sandpaper adhered to a large, flat surface. Stand up the body and trace its outer edges on the bottom piece, then cut it out on a bandsaw. Glue the bottom to the underside of the holder.
Sanding and Finishing
Finish-sand the entire project. I like to sand a small bevel on the upper corners for a softer appearance. I also sign my project by stamping my initials on the bottom. Remove all sanding dust and apply your finish of choice. For the project shown, I applied a few coats of Old English lemon oil. If desired, mount a few self-adhesive felt dots on the bottom.
One last step to finish your project and do away with your holiday worry. Gift-wrap the pen-holder, and enjoy the smile on the face of the lucky person who receives it, as well as the puzzled look that follows once the present is opened.
Charles Mak - [email protected]
Charles is one of the few hobby mechanical sculpture-makers in Canada, and likes to design and include mechanical elements in many of his projects.
