An assembled Prusa Mendel
The RepRap project is an ambitious open-source project with the goal of creating an affordable, self-replicating 3D printer. It is one is the oldest and most affordable consumer 3D Printers on the market today, and has several designs to choose from. However, since there are many different RepRap models (each with their own design goals) it can be difficult to sort through all the different options and choose one best suited to your needs. This post intends to serve as a brief introduction to the major types of RepRaps and their major differences. All types of RepRap printers can be built from scratch using a selection of widely available parts. In addition, a number of 3D printing retailers offer pre-assembled RepRaps for an additional fee.
Prusa Mendel (Iteration 2)
One of the most popular of the RepRap models, the Prusa Mendel Iteration 2 replaces the older generation Prusa Mendel design (Iteration 1), and comes with several notable improvements including:
- Enlarged print area, smaller machine size
- Lighter and more portable than the first iteration
- Improved constraint on the z-axis to eliminate jamming
- Easier to assemble
- Better axis efficiency
Using standard infill settings, the Mendel has a 15.0 cm3 per hour solid extrusion rate (which is equivalent to a built volume rate of 19.0 cm3 per hour) with 3mm filament. A Prusa Mendel costs approximately $520 USD to assemble, and although easier to put together than a Darwin, it can still be fairly tricky and requires some experience in working with machinery. Additionally, the Prusa Mendel also has the ability to be turned into a tri-color model with three extruders. The Mendel has an 8″x8″ build platform area.
A wood frame Prusa i3
The third iteration of the RepRap Prusa is an improvement over the past two designs and is actively being developed by RepRap developer Prusajr. The major improvements over version 2 are:
- An improved frame rigidity (to prevent x axis backlash)
- Parametric files for multiple size bearings or bushings
- Easier to assemble than the i2
The i3 can use two different types of print bed (single sheet frame or a box style frame). Although they achieve the same effect, the single sheet requires specialized tools to work with, whereas the box frame is easier to work with. You can also use two or more extruders with the i3, allowing you to print single objects with different colors and materials It costs approximately $450 in parts to build a Prusa i3 although many 3D printing companies offer pre-assembled Prusa i3 kits for an additional fee.
Based on the popular Prusa Mendel design, the MendelMax adds a larger print bed and has big improvements in rigidity over the Prusa Mendel for a slightly ($80) higher price than the regular Mendel. The MendelMax has a working build area of 9″x10″x”7″ and uses a new frame design to make it stronger. It costs approximately $600 to build a working MendelMax.
The simplistic Printrbot
Designed to be the simplest and most affordable 3D printer on the market, the Printrbot comes with the option to use either 6″x6″x6″ (regular), 8″x8″x8″ (pro), or 4″x4″x4″ (Jr) build platform sizes. With its simplistic design and a 101 part count, the Printrbot can be built for as little as $400 USD.
This guide should cover most major RepRap models, and acts are a brief introduction to the world of self-replicating 3D printing. If you currently have access to a 3D printer, you can models for most RepRap parts here on Thingverse.