This OSAT is appropriate for any locale that has access to a 3-D printer and needs additional learning materials for their curriculum. This is appropriate both for and as a game to teach young children between the ages of 4-9 how to follow rules, how to recognize and apply knowledge of numbers, and how to critically think.

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Bill of Materials and Cost Savings[edit | edit source]

Each domino uses 1 gram of PLA 1.75mm filament. At the recommended 130% scale, it uses 2g of filament per domino. For a single domino, that is For a full set of 28, that is 28 grams/56 grams of filament. Pricing filament at $23 per kilogram, that brings the cost for a full set out to 64 cents (or $1.28 for the larger, 130% scale version) USD.

Comparable sets of dominoes off of Amazon cost $15, creating a difference and savings of approximately $14.36($13.72 @ 130% scale).

Tools needed[edit | edit source]

No special tools are needed for the fabrication of this OSAT besides 1.75mm PLA filament and a 3D printer similar to a "Jellybox", or any RepRap printer.

Skills and knowledge needed[edit | edit source]

Interested in making this OSAT? You only need to know how to use a basic 3D printer, retrieving the design off of the World Wide Web and getting it to your printer. There are no supports needed, no rafts used. This design is 100% ready to go, easy to print.

Technical Specifications and Assembly Instructions[edit | edit source]

I find that printing these dominoes between 100-130% scale looks best, if they are printed at the default size they are a little small. Printed with 30% infill for appearance quality, ensuring no strange warping occurs across the top layer. I also printed at ".5" layer height for appearance sake, but this is not necessary. Printing at "1" layer height creates an optimal level of quality for the number bumps. Printing at "2" layer height may cause the number bumps to easily get broken off. Print at 100% speed and at 210 degrees Celsius.

Common Problems and Solutions[edit | edit source]

If you print with a 2 layer height or higher, it can cause the number bumps to fall off the top. Make sure to print at 1 or less. Printing at 1 or less will give you a print time of 30 minutes for 1, or 45 minutes for .5