3D printed duplicate of the Digi-Comp II marble pc / Boing Boing

Michael Gardi (the identical man who made the Think-a-Dot “computer” toy duplicate, and the Dr. Nim game duplicate) made a 3D mannequin of the mechanical Digi-Comp II marble pc so anybody can 3D print certainly one of their very own.  “I now have the entire assortment E.S.R. Inc. merchandise!” says Michael.

From his Instructables web page:

Digi-Comp II is a mechanical pc invented by John Thomas Godfrey and manufactured by Schooling Science Analysis (E.S.R., Inc.) within the late ’60s. As could be seen within the photos above, the gadget consists of a body (about 14 by 28 inches) propped up at an angle. Computations are carried out by balls rolling down channels on the highest of and contained in the platform via gates. Some gates are fastened switches that merely redirect the ball down a specific channel whereas others are flip-flops that each redirect the ball and alter the state of the flip-flop within the course of.

Supposed as an assist for instructing pc ideas, the Digi-Comp II can depend, carry out primary arithmetic, and procure both the “1’s” or ‘2’s” complement of a quantity. The gadget could be run in auto mode the place the balls are launched routinely after every step of an operation till the operation is full, or in handbook mode the place the consumer initiates every step.

Together with the STL information and directions for this mission, one can find a PDF of the handbook that got here with the unique Digi-Comp II. I introduced this file to an area copy middle and had them print me the spiral certain booklet you’ll be able to see above and I am actually pleased with the outcomes. Additionally there’s a PDF of the components and meeting directions that you will want to finish this Instructable.

This providing is a full measurement working duplicate of that Digi-Comp II from 5 a long time in the past. I’ve tried to make it as genuine as doable based mostly on the photographs and applied sciences that I’ve accessible to me. The unique high and inside decks as an illustration had been vacuformed plastic connected to items of masonite board, and the flip-flops and switches had been injection molded. In my duplicate the decks and items are all 3D printed. Additionally I do not need an authentic Digi-Comp II to work from. I’m indebted once more to Jaap Scherphuis (he did the unique video you’ll be able to hyperlink to above) for his invaluable help in offering me with good high quality photographs. Lastly I did modify the design of a few of the flip-flops (that aren’t seen when working the gadget) to enhance their reliability.