Making a Fraction Calculator

The video begins with the host introducing a DIY project to create a fraction calculator, inspired by a previous show where one was used. The original calculator is no longer available, prompting the host to make their own. The project starts with laying out two circles, each to be divided into 64 equal sections. A spoke generator program is recommended for this task. The host demonstrates marking values from 1/64 inch increments around the circle, starting at a designated zero point. A second, slightly larger circle is then drawn, with lines extended from the segments to mark drilling points for holes. The zero point is marked in black for clarity. The host also discusses a mistake made during the marking process and how it was corrected.

The second paragraph details the creation of the top wheel of the fraction calculator. The host instructs to choose a starting point and mark fractions in increments of 1/64, going counterclockwise. A circular mark is made for a thumb hole to hold the calculator, and a cut-out section is planned for the zero point to serve as a stop mechanism during calculations. The host also discusses the process of creating a PDF pattern for the wheel and the use of hardboard for the material. The video then transitions to attaching the patterns to hardboard using spray adhesive and proceeds to cutting the shapes on a scroll saw.

In this section, the host focuses on drilling holes in the larger wheel for assembly and using a brad point bit for clean cuts. The top wheel is then aligned with the larger wheel, ensuring the perimeters match, and a central hole is drilled through both pieces. Drive pin rivets are used to fasten the two discs together, allowing the top wheel to spin freely. The host demonstrates the basic functionality of the fraction calculator, explaining how to add fractions by aligning marks and spinning the top wheel until it hits a stop point. The process for subtracting fractions is also briefly touched upon.

The host identifies an issue with the prototype's handle, which obstructs the view of certain fractions. They decide to revise the design by removing the handle and replacing it with a simpler method to hold the calculator. The video shows the process of disassembling, modifying, and reassembling the calculator with a new drive pin. The host also suggests alternative fastening methods, such as using a nut and bolt or a nail, for those who do not have brass drive rivets. They emphasize the calculator's utility in a workshop for simplifying the addition and subtraction of imperial measurements.

The video concludes with the host expressing gratitude for the viewers' engagement and interest in the fraction calculator project. They offer the pattern for the calculator as a token of appreciation, inviting viewers to contact them via email to receive the PDF file. The host also encourages viewers to like, subscribe, and turn on notifications for future episodes. They reflect on the time-consuming process of creating the pattern and express hope that the viewers will find the calculator useful in their own workshops, suggesting potential modifications such as adding decimal equivalents of fractions.