( 30+) 5/8" ball bearings, available from Amazon and others, about 4 for a dollar. Good idea to get extras and make a few extra sets in case a group of three breaks apart when it gets dropped or banged into something.
(1) small square of wood about 3.5" x 3.5".
(1) another square of wood about 7" x 7" for a base to store the pieces , optional.
You need the Origin for the basic project.
A table saw or a simple router or router table will help fancy up the edges.
Two possibilities for router bits:
A common 1/4" bit from the Origin kit will do an OK job.
For a much nicer/softer transition from the side to the bottom of the recess you could use a cove nose bit. The examples in the images were made with the excellent Whiteside Model RU2075CN upcut spiral with a 1/16" corner radius (~$25).
Alcohol to clean the bearing before gluing.
Glue. I suggest a gel CA glue and activator, see description for details.
Sandpaper and your finish of choice. The examples were finished with Osmo.
This is the simplest and fastest of projects because it uses the Helix Drilling function. As such you don't move the Origin while cutting, it does all the moving around for you after you select a recess. It takes about 10 seconds per recess. You want to let it go around a few extra times to polish up the recess.
After placing the file, set the depth to .11" and cut the recesses. Note that the file is coded with the recesses as through-holes and not pockets, because pocketing can't use the Helix mode.
The most challenging step is gluing the ball bearings together. Making a couple extra scraps with the puzzle pattern is highly recommended as that will be used to position the bearings correctly. You can use the final puzzle base for that, but you may get glue on the nice base and mess it up.
This can be easy or hard depending on how you approach it.
I used a thick CA glue, Bob Smith Industries Maxicure and an activator. I love the stuff and keep a $22/8oz bottle in the fridge. I Always Use Nitrile Gloves to protect my skin from being glued to random items.
I protect the work surface by laying down 3M HD packing tape, CA glue won't stick to it.
Clean the bearings with alcohol
Use scrap to quickly make a couple extra hole patterns, set bearings in the holes. Leave working space around each set of 3.
With a set of three in the holes put a nice drop of glue at the two intersections. It will start to sag around the intersection and actually will get around the entire joint nicely. Have the activator spray nozzle unscrewed from it’s bottle before you start this, and lift the nozzle assembly out of the bottle and let a drop of activator fall from the bottom of the nozzle tube onto each intersection. Wait 30 seconds and you can set the bearing set aside.
You want to go pretty quick, don’t do more than two intersections at a time. The glue drop wants to sag down around the bearings, form a drop and fall. If you move at a smooth pace you get activator on the glue just as it connects at the bottom of the joint and you get a very nice connection.
The puzzle itself is quite difficult, it took me 2 1/2 hours to solve.