A burr puzzle, also known as an interlocking puzzle, consists of notched pieces of wood, plastic or metal that when put together creates a three-dimensional shape. The burr puzzle shown here is a modified version that was part of a prize pack from Instructables for a puzzle contest I entered a while back. The difference in this puzzle is the scale. The original puzzle trapped a small red ball. All parts for this puzzle were scaled up in order to trap a golf ball. Besides being readily available, I thought the golf ball would make a nice conversation piece.
For the build, I collaborated with Kevin from Kev’s Woodworks. Note that Kevin is 2000 miles away from me so all communication was through email. We both worked from my drawing but didn't discuss how we would approach the build.
As you will see below, this puzzle is pretty easy to build. The build from my part was documented with pictures. Kevin took it a step further and recorded his steps as shown in the video below.
I've also include 3D print files (step 12) for anyone that would like to print the puzzle. With that, I will give an Instructables premium membership for the first person that 3D prints this design and post a picture of it in the comments. Note that I'm not sure the slot widths will work on all printers. Therefore, I suggest you build two pieces and guarantee fit before proceeding to the entire build.
Step 1: Tools/Materials
- Table Saw
- Router Table
- 3/4" Router Bit
- Tape measure or calipers
- Wood - 1x6 by 12" long
- Paint, Stain, or Clear Finish (optional)
Step 2: Drawings
You will be building to this drawing. As you can see, there are only two different parts to the puzzle. You will need 10 of the cyan colored part and 2 of the magenta.
Step 3: Starting Board
I cut a 1x6 down to 4.5" wide. Not that the actual thickness for a 1x6 is 3/4". Depending on how you route later, you might want to sand this board down by ~ 0.02". I didn't need to do that since my 3/4" router bit produced a 0.765" wide cut. The important part is that the material fit nicely into the notches that you cut.
Step 4: Main Slots
Two of the three slots for the parts are cut on the 4.5" x .75" board. These slots were done on the router table. That's Kevin in the picture.
Step 5: Cut Pieces
The individual parts can now be cut from the board. I used a table saw without a sled. Kevin shows a nicer way of making these cuts - see the video in the intro for more info.
Step 6: 3rd Notch
If you didn't see it in the drawing, this notch is the difference between the two parts. To me, this was the hardest step since the parts are small and I don't like to get my hands close to rotating machinery. I cut two pieces of scrap and ran them through the router. I then positioned the part between them and ran the set across the router. Kevin built a sporty jig which would definitely be faster/better if you were building multiple puzzles.
Step 7: Sand and Finish
I didn't spend much time here - just cleaned up the edges. Once sanded, I finished the parts with Danish Oil. Kevin didn't add any finish to his.
Step 8: Final Pictures - Mine
This version was built out of oak.
Step 9: Final Pictures - Kevin's
Kevin used cherry for his build.
Step 10: Solution Pictures
The puzzle is pretty daunting with 12 almost identical pieces in your hand. However, it's really not that complicated.
- Start by separating the pieces (find the two that are different)
- Build the center section - straight forward
- Add the vertical pieces - this almost takes a helper
- Use one of the two pieces and a standard piece to make an X (make two of these)
- Insert and rotate the X section onto one of the sides
- Turn puzzle over
- Drop ball into puzzle
- Add final side
If that wasn't clear, see the next Step for the Video Solution.
Step 11: Solution Video
This video should be easier to understand compared to the pictures.
Step 12: STEP & STL File
I've included STL files for anyone that would like to print the puzzle. If you print it, please post a picture.
Step 13: Final Thoughts
We were both happy with how it turned out. The experience of having a "build off" from someone on the opposite side of the country was also pretty cool. If you liked this, please see my other burr puzzles shown here and here. As always, if you have any questions, feel free to leave a comment.
Thanks for Viewing!