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projekte:reprap

RepRap Mendel Prusa

reprap is a free 3d-printer (open-source/open-hardware). this post will document the building progress and give more information about getting access to it once it's usable.

getting access and usage

it's important for us to make it accessible to builders, architects, engineers, designers,… we're not sure about the billing process (material costs) of the material and the printing times, etc. but we'll figure that out once we have a stable version of the reprap.

config-file for the slic3r settings: slic3r_config.ini.zip

firmware (as a backup): teacup

firmware update 12.12.2012: marlin

building process

we've decided to build a mendel prusa deluxe version with linear bearings instead of only plastic bushings. that should make it a lot easier to print with better quality, but we're not able to proof that right now.

mechanics: mounting the frame

we got our rods, screws, nuts in a hardware store (hornbach) and we got almost everything we needed except the smooth rods and some less important things for about 20€. very important: we decided to buy self secure nuts for the frame. that turned out to be a huge mistake. it was a hell of a work to screw the nuts and adjust it!! at least it won't unscrew that fast now… other than that, there's not much to say about the mounting. we used the prusa manual that is available on the reprap wiki. our prusa version was not exactly the same as described in the manual, but with a little imagination that was not difficult to handle. the only little thing that we misinterpreted at first were the couplings of the z axis. after adjusting the firmware we figured that the screws in those couplings we for adjusting the displacement of the z axis. it's really hard to do that, but compared to the old coupling version it's possible, at least.

electronics

after comparing lots and lots of information about existing boards we decided to make an own version based on gen7 with a few minor changes. designing a new prototype board always causes errors. more information soon

supplier list

  • cheapest stepper motors we've found, pololu-drivers: reprapworld
  • pcb production: eurocircuits
  • electronic parts: reichelt
  • rods, nuts, washers, etc.: hornbach hardware store (everything except the smooth rods that surprisingly just came from somewhere….)
  • plastic parts, extruder, bearings: reprap-fab

firmware

right now we're using the teacup firmware. for that we needed to flash the arduino bootloader. the reprap wiki has informations about how to do that. since arduino mostly addresses people who are not familiar with electronics and just grab an arduino board and start programming (correct me if i'm wrong!) that might have been the reason why most of us haven't used the arduino software before. it took us a while to figure out the little glitches that came with it. i'm mentioning the hundreds of timeouts that we had. after reading endless threads about these we figured that adding a simple reset switch does the job (it's a temporary switch that nicely fits on the pin 5 and 6 of the isp-connector that is not needed when programming with the arduino software via usb).

after flashing the teacup firmware, we were able to see moving axis already.

software

you suppose you have made a 3d model with any 3d-modelling software that you like (solidworks, pro engineer, catia, or any free tools like freecad, openscad, etc). what we need is an stl-file (stereo litography) that any of the mentioned programs are able to export. that file needs to be opened by a slicer-tool. what we currently use for that step is slic3r. the slicer-software calculates the extruder path for each layer and generates a GCODE-file. that GCODE-file needs to be opened in printrun, a GCODE-sending application that communicates with the reprap-electronics.

the configuration file for the slic3r is available on the turmlabor computer and here.

sponsoring

since it was my first try to apply for sponsoring i'd like to give a few advices of how to prepare a project and get money. it's meant student from the lab. i would have been glad to have some kind of a guide…

when i first read about reprap, i was really fascinated by the idea of printing stuff in 3 dimensions at home, for cheap and so were a few of the people i talked to in the lab. the only problem was: even if it's just about 500€ it's been very hard to convince poor students of investing a few euros. after waiting a few months for anything to move i started writing a concept paper of six pages about the project, the philosophy, the possibilies, etc. i added a 3d model, price comparisons, informations about printing material, thingiverse, and a few other things. enough to convince it's a full and working project, but not a few hundred pages that no one wants to read. any other person i asked for help had another idea of what it should be like, so it took me a time ti finish it.

that being done i contacted the student representatives of the faculties information technology, electrical engineering and mechanical engineering about the project. a attended a weekly meeting of each faculty and presented the idea. the concept paper was just a handout so the students would have a picture and a few further information to skim through. i also told them about the other possible sponsors. that way they discussed an amount of money that they could support us with and voted. (i calculated that we need 500€)

it all worked out very easily with no problems. it's important to know: they have money and usually they want to spend it.

our plan b would have been to address the student representatives of the university, professorships that might even deal with research in any of the reprap fields (material, 3d modelling, robotics,..) or different companies.

projekte/reprap.txt · Zuletzt geändert: 2014/03/15 17:50 (Externe Bearbeitung)