Part 1 M1EC one cylinder engine keychain

thingiverse

Here is the translation: **History** I have a weakness for printing movable objects. So, I once printed an object for my keychain, which surprisingly had smartphone dimensions. It barely fit in my pocket, but the gears worked well, even if they just wandered around uselessly. So, I came up with the idea to build a smaller and more meaningful object as a keychain, first a miniature single-cylinder engine. I got carried away and immediately developed a universal system that can create V-engines, boxer engines, in-line engines, and radial engines, including an 8-cylinder V-engine. These engines are feasible in three variations: with clips, screws, or ball bearings, or a mixed design (hybrid). However, a big clipped engine makes little sense, just as a ball-bearing is hardly necessary in a single-cylinder engine. **Construction** * All engines have the same piston and are connected to the connecting rod via a M2 x 8mm cap screw with nut (total 10mm) as a piston pin. This one screw is recommended, but it's also possible to replace it with a short piece of 2mm wire or 10mm of your PLA filament and some glue. * The connecting rod is available in several variations. In the standard version for clips, the connecting rod is 2.5mm thick. * The cylinder is basically the same for all engines and differs only in some engine cylinders in the type of trapezoidal webs (mounting to slide on the base - the "crankcase"). * The cylinder head is identical everywhere (unless I build a variant with valve timing). There is also a variant with a ring for a keychain. For optical reasons, I recommend fixing the cylinder head with four M2 screws. * The crank (shaft) differs in the engine and mounting variants. The gear shape is without function and has only optical reasons (However, the drive is also thought of an electric gear motor, then the gear gets a sense again). * The base, in a sense, the crankcase, is actually different in each engine due to the design, just because of the different cylinder arrangement. **Miscellaneous** * As a tool nothing is required except the key for the screws. However, some sandpaper, a few small key files, a craft knife and possibly a 2mm drill (and later 3mm) may be useful. * For the "Press-Fit" trapezoidal guidance of the cylinders, I use printed auxiliary tools for pressing on and off, which are not absolutely necessary. For more installation instructions, I speak with the more complicated designs. * For a small exhibition cabinet of the models, there is a stand, with some other base must be used. * Since the crank wheel is difficult to access in some engines, ball bearings can be fitted with an external gear to operate the motor (also for later electric drive). **Technical data M1EC** * External dimensions: length 53mm, width 25mm, depth 20mm * Weight: a few grams * Cylinder bore 11.5mm, stroke 13.1mm, displacement 1.36 cc, hardly compression * Printing time on Anycubic I3 mega at 100% filling about 45 minutes * Assembly time approx. 5 minutes **Perspective** This is the first part of the overall project using the example of the M1EC (single cylinder engine clipped). I would like to continue the project through a workshop and introduce an extension or other engines every few days. Since all this with the documentation is very time consuming, I would be very happy about a tip.