After posting my “Floor Dominoes” project, several readers expressed interest in how the dominoes were made. I wrote the following article and, with minor differences, it has now been posted on both Lumberjocks and on Rockler Woodworking’s “Buzz Saw” site.
Set size: Mine is a double-nine rather than a double-six set, even though more than twice the work was involved. The additional work is because a double-six set has only 28 pieces and 168 pips, whereas a double-nine set has 55 pieces and 495 pips.
Wood selection: Wooden dominoes are not for ‘serious’ domino players since irregularities in wood color, grain, and construction make them easy to ‘read’. This problem is relatively unimportant for this kind of set, but can be minimized by selecting wood as nearly uniform as possible, and by using care when making them. My first set was pine and unfortunately warped and did not machine well. This second set was made from scrap Philippine mahogany, and while not the ideal wood, it was stable and light weight, and machined well – all necessary characteristics. Overall, the mahogany turned out to be quite satisfactory.
Domino size: A domino is normally twice as long as it is wide – making a square at each end. Note that pip size has a significant bearing on the size of the domino. Pips are laid out on a square grid with nine possible pip positions, and the size must accommodate not only the pips, but also the spaces between them and around the perimeter. I used AutoCAD to try out various pip sizes and spaces before I settled on 1/2” diameter pips and an overall size of 2-3/4” x 5-1/2” x 5/8” as shown on the close-up of the ‘3-7’ domino below.
Pip cutter: A core box router bit would make a pip similar in shape to that used in most dominoes. This would likely work well with a plunge router and a template, but perhaps because my bit was dull – or that I was using a drill press – or the pine was too soft – or more likely all of the above, it simply didn’t work well for me. The pip holes had both rough bottoms and rough edges – leading me to switch to a Forstner bit and colored paper dots.
Coloring pips: If I had been successful in cutting smooth, accurate pips with a router bit, I could either have left the pits natural or painted. While thinking about painting round-bottomed pips, I decide the easiest way would be to paint the pips quickly – with little concern about misplaced paint around the edges. After the paint dried thoroughly, it would have been a simple matter to re-sand the faces to remove the excess paint. With smooth pip holes, this would have worked nicely, and would likely have been about as fast as the flat-bottomed holes and colored paper dot system I used.
Cutting blanks: For a number of reasons, cutting accuracy is very important when making domino blanks. In addition to needing to be identical in size, blanks must also be perfectly square in order to have accurately aligned pips. When cutting the blanks, I made a number of extras beyond the 55 needed for the set. These extras were used for test purposes, and to have matching blanks available if needed for replacement.
Division line: I cut my division line on a table saw with a 1/8” blade, but for a more finished look, a “V” shaped router bit could have been used. Incidentally, I made the division cut after all pip holes were drilled, but before sanding.
Drilling: My layout and drilling method is simple, but difficult to describe. A drill press, a fence, two fence stops, and four identical drilling ‘spacer blocks’ are required.
Before making the actual drilling setup, I marked (as accurately as possible) the exact drilling center of the pip on one end of what would become the ‘1-1’ domino. No further layout marks were required.
The width of the spacer blocks is the combination of a pip diameter plus the space between pips. Since my pips were 1/2” in diameter with 1/4” between, my spacers were 3/4” wide. Except for convenience, spacer height was unimportant, but the length needed to be about the same dimension as a domino width.
The next step was to establish the fence location. First, I tightened a 1/2” sharp-pointed Forstner bit into the drill press chuck and lowered it so the point barely cleared the marked domino blank. Then two end-to-end spacers were placed between the marked blank and the fence. The sole purpose of this step was to make certain the fence was located so that the point of the bit would fall along the exact longitudinal centerline of the blank. The marked domino was held snugly against the spacers and fence while moving the fence until the sharp point was directly above the pip mark. The fence was not tightly clamped until the domino was rotated end for end several times to fine tune the centering.
The next two steps established locations of the fence stops. With the rear spacers still in place, I located one stop by putting a spacer between the long end of the domino and a stop while centering the sharp point of the bit directly above my pip mark. After rotating the domino, the second stop was located in the same manner. This completed the setup, allowing every pip for either double-six or double-nine sets to be drilled by moving only spacer blocks. Neither the fence nor the stops required further relocation. I found it unnecessary to clamp the blanks while drilling. Simply holding the blank firmly against the fence, stops, and guides was sufficient. As a final test of my setup alignment, I drilled all 18 holes for a ‘9-9’ domino in a spare blank.
If the above is confusing, hopefully the following drawing will help. If you have trouble reading it, and will send me your Email address, I’ll be happy to send you a copy in PDF format.
This method of spacing and drilling will work with dominoes of any size, and I thought it was reasonably fast. Drilling all 495 holes for my double-nine set took about an hour and a half. The following picture shows the entire set after drilling.
Routing: Domino edges and corners need to be softened. I used a 1/8” roundover rather than a larger one to retain as much of the flat edge as possible. The width is especially important when the dominoes are used on a rug. A chamfer bit would also have worked well. All routing and division cutting was completed before sanding.
Sanding: Even with a sharp saw blade, some sanding was necessary. Faces and backs had to be sanded individually, but edges were sanded about a dozen at a time. I did this by carefully aligning and clamping the dominoes together and using an electric finish sander. I was careful not to round over the end dominos – but in retrospect, it would have been a good idea to use spare blanks at each end of the queue to eliminate that potential problem.
Finishing: Knowing that my ‘floor dominoes’ would get rough use, I chose to use a penetrating finish (Danish Oil) rather than a surface finish. Tung oil or any other penetrating finish would have worked as well. To make sure the colored dots would stick well, I tried to avoid getting finish on the bottoms of the holes.
Paper pips: I used AutoCAD to lay out and print sheets of various colored dots on heavy, matt-surface presentation paper. Rows of dots about 5/8” in diameter allowed a little tolerance while cutting out finished dots with a 1/2” paper punch. I liked being able to choose the exact colors I wanted, but I could simply have cut the pip circles out of heavy colored paper. I applied Titebond II to the bottoms of the holes, but any glue should work for this purpose. In my case, the pip dots were a snug fit in the holes, so it was unnecessary to be very thorough or accurate when applying the glue. I used a 1/2” rare earth magnet stuck to the bottom of a steel rod to tap the paper dots snugly against the bottoms of the holes. Since the dots were the final step, after a little drying time the dominoes were ready for play.
Storing: I have a couple of small drawers near the floor area where the dominoes are used, so that’s where I keep them. I could have built a container in any number of configurations – and may yet someday. I’ve considered a box with or without a lid, and with or without casters or wheels – a rope handled open-top ‘box’ – a wooden wagon – etc.
Shortly after completing the dominoes I had a number of visitors. It was a pleasant surprise to find that both adults and children enjoyed playing with them. Any toy or game project that is well-enjoyed is worth the effort. I hope this information will be helpful to anyone who would like to make a set. If there are any questions, please post them.
-- Dave O.