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1. a mechanical device of any sort, especially one that is complicated
2. a device or control that is very useful for a particular job
3. a construction made of whatever materials are readily available

What is Contraptor?

Contraptor is an open source construction kit for experimental personal fabrication, desktop manufacturing, prototyping and bootstrapping. It can be thought of as user-extensible Erector set with linear motion components. Various Cartesian robots can be quickly assembled from Contraptor and used as a platform for projects such as XY plotter, mini CNC machine, 3D printer etc.

Contraptor is an ongoing project under development. One of the original project goals is manufacturability at home with only basic tools, using inexpensive materials and parts readily available in hardware stores and online, with cost in the range of $400 and without the need for a custom-manufactured kit.

Contraptor is mechanically compatible with 1" T-slot (such as 80/20 Fractional 10 profiles), pegboard, 1" grid beam (such as commercially available perforated steel tube), and likely other things with dimensions standartized in 1" grid. 

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How it works

What can be built

How to make it

How to contribute

Latest Release 

Contraptor 1.5.0 - http://contraptor.svn.sourceforge.net/viewvc/contraptor/tags/contraptor-...

Credits

Contraptor was inspired by the Kulibin CNC construction set, featured in MAKE magazine. While the idea is the same, the design is open, user-extensible and oriented towards making the set from scratch.

License

Plans, designs, templates, assembly instructions and other Contraptor documentation are licensed under Creative Commons Attribution-Share Alike 3.0 License. This basically means that you are free to manufacture and sell existing and new Contraptor components as well as their assemblies, mods and derivatives, as long as you a) release your designs back to the community under the same license and b) provide attribution:

CONTRAPTOR garageFab.cc/contraptor

Contraptor components

Perforated angle The main building block of the Contraptor set is the aluminium angle with 1/4" holes, centered and spaced 1" apart. The angle is the structural component as well as the linear rail for sliding elements. The angle is used in lengths of: 1", 2", 3", 4", 6", 9", 12", 18", 24". Longer lengths are possible but not very usable because the deflection increases with cube of the length.
Sliding elements Sliding elements are the linear motion components, the carriages (or trucks/trolleys) which slide on the perforated angle. Sliding elements are driven by belts or leadscrews.
Pulleys, belts and clamps Belt and pulleys drive the sliding elements directly using belt clamps, or connect two or more parallel leadscrews, which in turn drive sliding elements.
Leadscrews and leadnuts All-thread rod drives the coupling nut, clamped in the coupling nut clamp, which in turn is attached to the lead nut mount. The lead nut mounts are placed inside the sliding elements and held by screws.
Shaft mounts A pair of shaft mounts support shaft with a pulley or a leadscrew in appropriate alignment, using a pair of ball bearings.
Motor mounts The motor mount is used to attach NEMA 23 size stepper motor to the frame. It also conducts the heat from the motor into the frame. To couple the motor shaft to the leadscrew, inexpensive spider coupling is used.
Captive nuts The captive nut accepts a long screw. Several of these can be used to quicky fix a tool such as drill or dremel to the frame.
Fasteners The set uses generic nuts and bolts available in hardware stores.
Stepper motors The set uses NEMA 23 stepper motors. Steppers of this size are ubiquitous with large choice of parameters. The recommended stepper motor is 44A501711 by Applied Motion Products, with price of $10 and current rating of 2.3A.
Stepper driver boards The set currently uses open source stepper driver boards from the RepRap project. Each motor requires one driver board. Couple of neat features of the board: it can be powered by a PC power supply and it has the ability to adjust the current flowing through the motor coils. The L298 chip must be heatsinked! It can be attached to the frame using perforated angle, that way entire frame acts as a heatsink.
Controller The controller currently used is Arduino. A subset of G-Code can be run on Arduino, using the Arduino GCode Interpreter from RepRap project. Arduino clones/derivatives such as Freeduino and Sanguino should work as well. In general, any controller with enough digital outputs (and appropriate control software) can be used to drive the stepper driver boards.
Power supply The power for the stepper boards is provided by generic ATX power supply unit from a PC. This one is 300W model. The Arduino controller is powered by USB bus.