You may have recently seen advertisements for UGEARS, maker of some incredible moving models made entirely from precision laser-cut plywood parts. We laid our hands on several STEM Lab kits and are going to feature our builds of each model over the next few weeks. These are projects that can be made generally in less than a day, and provide multiple avenues of entertainment and education. Each model improves the maker’s ability to assemble a model, fun in itself, but like LEGO expert builder series models and Erector sets of the past, these models are engineering marvels that replicate machines for mathematics, physics, and engineering study. More advances models in the catalog include working trains, cars, and a dragon with moving wings, which we’ll work up to.
First, let’s take a look at the Multiplier and Addiator builds, both included in the UGEARS 2-in-1 Arithmetic Kit (available here directly from UGEARS or here at Amazon and also via model shops and online game and craft stores) tools students from grade school through college engineering can use and display, featured as one of the starter builds in the UGEARS catalog.
The box includes everything you need two make both calculators, 5 sheets of pre-cut plywood, a piece of wax crayon to reduce friction, and a spacer (which doubles as a stylus) and a press-out tool to ease removal from the sheets of smaller pieces.

The box suggests these box can be built in less than 3 hours and we confirmed that to be the case. The recommended age is 14 and up, but with assistance from an adult, grade schoolers can also get some early insight into both model making without the need for glue, and, of course, basic math skills.
The instructions were clear (written, with color visuals), and available in 9 languages, and an augmented reality option (QR code links provided) is included for further learning via a UGEARS app. The first build is the Multiplier, which takes about twice as long to build as the second calculator, the Addiator.

Let’s look at the Multiplier first. A rudimentary mechanical computer to multiply values using hinge levers, the benefit of this device is in part its geometry for future engineers, but it also allows for learning and checking of multiplication tables. Using two slides users can multiply two numbers from 1 to 12, as well as calculate their squares. Knowledge of matrices is a concept delved into in college first-year math courses, but young learners can gain development of understanding how matrices work by studying this device, and the angles of its mechanical armature.
The only skills required are patience and a gentle touch when punching out the 177 total parts. Most operations are tongue and groove fastening, along with reinforcements via pegs. These form slide mechanisms, with later UGEARS kits moving up to more advanced gears.

Following directions is a must (I had to redo connectors three times because I missed steps, and each time the parts came apart with some coaxing). Because this isn’t balsa wood, I also had no pieces break, an improvement over balsa kits of the past.

And the final model. Instructions and examples are provided to demonstrate how and why each component works. In short, move each slide to the numbers you wish to multiply, and the result is the product of those numbers.

By way of background the Addiator was invented in France in 1889, and was in production throughout the world between 1920 and 1982, when it was replaced with modern electrical versions. This Addiator adds and subtracts whole numbers with value totals up to 9,999. The “magic” of the Addiator is its “carry” mechanism, which allows the user to carry digits with a simple hook move of the stylus.


If you read our review of the Orpheus Music Box Robot Kit from Robotime, a wooden 3D puzzle music box craft kit that results in a steampunk desk-shelf cheerleader to lead you on as you plunk away on your keyboard, you’re already familiar with the building steps for UGEARS models.
All told, this took me less than three hours, taking my time, about 2 hours for the Multiplier and one hour for the Addiator. The result can be a powerful tool for young learners and part of a great science and technology desk set for engineers. In the next few weeks look for builds of a UGEARS Gearbox, a Variator, a Tachometer, and a Random Generator, plus one of the advanced build sets. Take a look at all the available UGEARS models here at Amazon, and check out the UGEARS website.
C.J. Bunce / Editor / borg