The TV Prusa design
Introduction
Our Thames Valley Prusa design is based on a standard RepRap, with a number of improvements based on the experience of the lead members of TVRRUG. Custom modular electronics have been developed based on an Open Source Multi-axis Controller project hosted by another member. These Thames Valley E-Modules are more functional and lower cost, they use mostly 'through-hole' and can be built from a kit with few tools and by those with little soldering experience.
Components list
The components list is being managed in a Google Docs Spreadsheet.
The Thames Valley RepRap has 4 main subsections in the Kit Sheet
Equipment: Tools needed to tackle the build Equipment
Electronics: Electronics Detail documented TVRR E-Modules
Vitamins: Misc Hardware, the nuts and bolts of the machine
Printed: Parts that can be Replicated by Printing on a RepRap
Getting the designs
We maintain an "official" git repository on github with all of the printed parts.
From March 2016 the Git;s are at this revised github address
The electronics are derivations of opensource hardware Open Motion Controller - OMC (original 1.1 version) and Dual Stepper Modules - DSM projects found at Solderpad
To checkout the very latest version of OMC git clone git://solderpad.com/folknology/open-motion-controller.git
To checkout the very latest version of DSM git clone git://solderpad.com/folknology/dual-stepper-motor-module.git
more design info available on the emodules page
Building the TV Prusa Round 1
Equipment: What you need in your tool-kit to start with
Soldering: Soldering and what you need to start
Frame: Starting to build the frame — basic triangles and Y-axis idlers
Second part of frame: Continuing the frame build — Y axis, Z axis and X axis rods
Third part of frame: Finishing the X and Y axes
Print Head: Extruder Assembly: Building the "cooler" part of the extruder
Print Head: Hot end: Building the hot part of the extruder
Electronics - v1.0: Electronics and electrical parts
Electronics check - v1.0: Modification, electrical test and check
Completing your TVRRUG: The final steps prior to wiring
Electronics wiring: The Wires
Electronics wiring: Connecting your Electronics
Firmware: Loading the Bootloader & Firmware
Changes when building the TV Prusa Round 2
Electronics check - v1.2: Electrical test and check for v1.2
Electronics wiring - v1.2: Connecting your Electronics
Frame Starting to build the frame — basic triangles and Y-axis idlers
Second part of frame: Continuing the frame build — Y axis, Z axis and X axis rods
Notes about R2 frame: Finishing the X and Y axes
Firmware for Round 2: Loading the Bootloader & Firmware
Notes for Round 3 Builders
Currently the notes for Round 3 are accumulating on the Google Group here
Build guide documents for download.
Chris is putting together a Hints & Tips page for those new to soldering.
All the printed parts should be checked for hole size and some prints may have undersize holes (better than oversize), some printers may have eased or fettled the holes for you, but others leave it to the builder to do, to get the best fit as the rods do vary by microns in size. The barclamp teardrop only allows a small amount of compression, and the bar need to be held firmly, so good sizing is important.
Regarding the barclamps: It is important to clip onto the threaded rod before inserting the rod into the teardrop.
The three-part guide to setting up by Rich Rap below is excellent, but it doesn't explain how to get the initial filament through the hobbed bolt and into the extruder head. You need the springs a lot looser (possibly 2/3 undone). Initially pull the compressor flap back against the springs, so you can feed the filament into the hole at the top of the extruder head. You can then let the compressor flap go and it will force the filament against the hobbed bolt. Then tighten the springs, although if you have the springs too tight you may find that the feed gears jump, because they can't get the filament through the gap.
Software
Firmware: Info on Marlin and perhaps Sprinter to be added Current Firmware repository.
Toolchain
3D design software: Blender, OpenSCAD, FreeCAD, Solidworks, Meshlab.
[ian commented recently in the GG, as follows: "One of the few is Meshlab, and it can be a very frustrating program to use, crashing a lot if you make a slight mistake in parameters, and there isn't even an Undo! However, in my quest for the perfect mesh, I have found these youtube tutorials (I'm sure there are plenty of others), which I think are presented by a guy who is involved with the coding of the program: http://www.youtube.com/user/MrPMeshLabTutorials?feature=watch
I have found them useful to correct a number of basic UI problems I was having, and for setting up surface reconstruction. Once you get used to it, it is a very useful and powerful program."]
As well as the OpenSCAD wiki, this tutorial is a helpful introduction
Slicing software: Slic3r is the preferred stl slicing tool at present. Use this page to guide you to better settings.
There is also a great guide to the settings by RichRap in 3 parts here:
http://richrap.blogspot.co.uk/2012/01/slic3r-is-nicer-part-1-settings-an...
http://richrap.blogspot.co.uk/2012/01/slic3r-is-nicer-part-2-filament-an...
http://richrap.blogspot.co.uk/2012/01/slic3r-is-nicer-part-3-how-low-can...
Other options are Skeinforge (lots and lots of options, can be confusing, and very slow to slice stl files) and SFACT (a re-factored Skeinforge designed for ease of use, but still complicated and slow).
Printer interface software: Pronterface aka Printrun
Repositories
The following Git repositories have useful data for use by TVRRUG, these are way you should look for the parts to re-print:
Calibration
An excellent 2-part guide (link here) to standard Prusa calibration. Some parts are not relevant to the TVRR design, but those will be clear to the reader
Alex has written an excellent guide to TVRR calibration which includes a link to the useful _40x10.stl single filament test piece that we recommend for testing Z axis setting, extrusion and retraction settings.
The first task is to set the 'Home' location. This can be done using the Pronterface aka Printrun application to drive the axes manually. 'Home' is when the extruder is at the front, left hand corner of the HotBed. The Z axis is adjusted to bring the extruder to within a paper thickness of the glass plate on the HB.. For this to be achieved the HB must be aligned to the travel of the X and Y axes. Initially you should level the surface the Printer is sitting upon, then level the Printer top bars, and then level the HB using the supporting screws that pass through the 'four bed springs'. Having got the bed level you can finely adjust the gap between the extruder and glass plate in the X movement by setting the motors to off in Prontoface and turning the left of right Z axis by hand to raise or lower each end as needed. When each axis is set then the micro-switches can be moved to trigger at this 'Home' position. You can use GCode in the Prontoface command box to drive the axes 'Home'. G28 code drives alll 3 axes together, G28 X0 for the X axis alone, G28 Z0 etc..
A definition of GCode from wikipedia (general)
Helpful reprap-specific guide to GCodes
Advanced gcodes used in Marlin firmware
- M114 it will report where it thinks it is
- G92 enables you to set position, so if you did 'G92 Z5' would set Z to 5
- you can set some or all axis at once e.g. G92 Z10 X100 Y100
- M106 S<50-255> turns extruder fan on, S is the speed, must be greater than 50 or the fan wont spin. M106 S0 turns it off again.
Printing
The minimug model for your first print: minimug
Hints and Tips from Builders experience when printing
