Wooden Domino Set Using a CNC

I am a 3rd year, Electromechanical student at the North-West University, in South Africa.

My family and I enjoy game night where we play card games and very often play dominoes, we bought our one and only set of plastic dominoes years back and after enduring years of playing the printing on the dominoes almost fully faded, it was time for an upgrade. I decided to make a wooden set of dominoes taking inspiration from a set I randomly stumbled upon on the internet.

The design and production of these dominoes is pretty simple and straight forward and with enough patience can be done using tools found in the workshops of most makers. I will be using a CNC for machining the pattern, but the pattern can potentially be made using a template and a drill press.

This set of dominoes can make a great gift and a great project that can be done within a few days of work.

Materials:

• Any wood of your choice (Maple in my case)
• Contrasting veneer (~0.5 mm)
• Wood glue (PVA)
• Packing tape

Tools used for preparing the wood:

• Bandsaw
• Thickness planar
• Drum sander

Tools used for cutting dominoes:

• CNC
• 2.5mm single-flute endmill
• 1mm single-flute endmill

Finishing supplies:

• Steel wool
• Danish oil

Before diving into the project head first, I decided to first do the designing and brain storming for the project. A google search of the standard dimensions for dominoes revealed that a standard domino is one inch wide and two inches long, as I will be working with the metric system I decided to make my dominoes 25mm wide and 50mm long. I have also found another article which provided the image and the "magic ratio" of Thickness = X, Width = 3X, Length = 6X. In my case that would mean my thickness will be 8.33mm, but for simplicity sake I will round it down to 8mm.

Now that we have the dimension it is time to plan out the set and design it in order to effectively cut it on the CNC (preferably out of one piece). Everyone might have different available materials and sizes, I have decided to position my dominoes in a 4x7 grid. This gives us a theoretical work piece of 100mm by 350mm (without any material for cuts), adding some material for all the cut to be made gives us an approximate size of around 120mm by 380mm.

Create all the dominoes and position them in a 4x7 grid layout with 4mm gap between the rows and columns. Other layouts are possible, my limitation was the width of the wooden stock I had available and therefore to maximize the usable space, 4 domino widths were ideal. The outside perimeter encloses the area of 120 x 380mm, as chosen in the previous step and helps visualize the work piece, it will also assist in the next step with the CAM setup. One consideration is the grain orientation on the dominoes when they are done, in my case I wanted the grain pattern to run along the length of the dominoes and therefore have to place the dominoes parallel to the grain length wise.

The CAM setup is a pretty long and tedious process and here I will not go into the explanation, there are way better and more qualified people on here that have done an amazing job at explaining Fusion 360 CAM setup step by step. I will attach the full CAD and CAM file below. In summary, I used the 2D pocket and contour operations to create all the cuts.

Find a piece of wood that is about 130mm and at least 400mm long, we want the final dimensions of the wood to be 120mm x 380mm x 7mm.Using a combination of a bandsaw, thickness planar and drum sander get the wood of your choice to the right size and thickness. The reason we want 7mm is that after gluing own veneer on both sides of the plank the final piece should be 8mm provided the veneer is approximately 0.5mm thick. In addition prepare your veneer by cutting a piece slightly oversized (125mm x 390mm)

In order to laminate the wood with the veneer, we will need to prepare two planks between which we will sandwich the glue assembly. In my case I am using two pieces of plywood which are slightly oversized in comparison to the pieces I'm laminating. Use packing tape to cover one side of both the pieces of plywood to prevent glue from sticking to them. Once you have that it's time to start the glue up.

Start by applying the glue to one side of the wooden plank and apply the veneer to that side, repeat the same steps on the other side and sandwich the piece between the pieces of plywood that were prepared prior. Try to apply even clamping pressure and allow the glue to dry for at least 24 hours, or longer if specified on the glue.

I unfortunately do not have any of the image during the machining and the finishing stages, but there one important note I want to address about the mounting of the workpiece to the CNC. Because I am cutting all the way through the wood, mounting clamps on the edges are not enough, I used double sided tape to secure the entire workpiece to the bed of the CNC.

After machining, I slightly sanded each domino removing the bur on the edges and prepared for the finishing stage. To finish the dominoes, I used Danish oil, this preservers the natural wood feel of the dominoes while till protecting them from wear. I applied two coat of the oil allowing 24 hours between coats and the dominoes were done.

Thank you.