I've always wanted to do a huge print of a statue of some sort on my printer, and I finally decided to print the famous beautiful owl statue by cushwa.
Here's the finished project.
Preparing the model for printing
Picture from thingiverse
I used netfabb Basic to cut the model into slices. I originally wanted the owl to be closer to 50 cm tall, but since the base of the owl is approximately square I would have had to print a lot more parts (as in ~16) to get finished. I therefore scaled it up to fit my 20x20 platform and cut it in three pieces to print.
I sliced it with Slic3r it with several perimeters and very low infill, to save time and plastic. I could have gone with even more perimeters and ever lesser infill on the centre parts instead, the result was more than rigid enough.
Printing the middle part on my trusty Mendel90
sturdy.
I printed with scraps of remaining plastic, which was a bit of a bad idea.
Here is the finished print before any painting is done.
Assembly
In total it was printed in four parts due to the filament clogging up a few times, so I had to measure and cut it several times in netfabb Basic. Notice the visible seam on the very top with the ears, and how they disappear later.
Attaching a model like this together was a bit tricky at first. I tried to heat the centre of the print to make it stick to the previous part, but it was impossible to heat a area that large fast enough and attach it together before if cooled of. So I ended up attaching using a soldering iron along the edge only, and it held up very well.
First I ran the iron through both parts, leaving some ugly but strong anchor points. Then I ran the soldering iron along the edge smoothing it as best as possible.
Painting
First I tried some plastic primer, but it reacted with the PLA in some way, and made it all soft. Instead I started out with this spray filler from Jula (norway/sweden). It was not as thick as I expected so it needed several layers with sanding in between, but it is very nice to work with.
First layers of spray filler.
Notice the visible lines in the eye sockets.
The spray filler was not thick enough to remove the larger seams,
so I added some wood filler. It all bonded surprisingly well.
I also had to sand it several times between spray filler and wood filler to make it smooth.
I really liked the colours in this shot.
I do believe this was the final sanding stage.
The back is feeling real smooth now.
The top still have a few layers of sanding and smoothing left, but it looked real good with the soft shine and reflections.
I was considering painting with a gloss paint at this stage instead.
From the front, all shiny.
Granite effect
I used this granite effect spray. It was very different to work with than regular spray and had to be painted on in very short bursts to avoid running. Luckily it dries very slowly (as in days) and you have plenty of time to wipe off and redo any mistakes.
For being handling safe it needs to be painted over with some kind of clear spray.
First test with the granite effect spray resulted in horrible running.
The granite effect hid the seams and lines extremely good.
After days of very thin layers of granite effect,
I gave it several (can't recall exactly how many, but at least 5)
layers of clear glossy paint.
Painting with the object laying like this was the only way to paint under
the feathers of the body, as the granite spray really doesn't like to be applied sideways.
Final result
Here are a few shots of the final result.
All the equipment used.
Thank you for reading, I do hope this inspired you to print something huge on your own RepRap. :)
Feel free to ask any questions about the process!
Inspired by Frits I bought some static model grass off ebay and tried it out on an old print from the shelf.
First I tried to use automotive spray glue, the kind you use when applying fabric to doors and such, but it was way, way to gooey and made a mess of the model. Since I didn't have any other spray glue, I tried applying a layer of clear spray paint and poured the grass over it. It stuck surprisingly well! I applied another layer of spray on top of the grass and poured even more grass over it, thus leaving it pretty well covered.
Here are a few pictures.
For a first test I'm very satisfied. It will be interesting to see how well it holds up, but it didn't fall off when touching, and the spray made it pretty static leaving an interesting looking effect.
The problem with a model this detailed is all the fine details is gone, this could be due to me applying several layers.
I will try with some landscape model printed in green plastic, to see how well it looks then.
Edit: I just tried rubbing it a bit, and it turned out most of the grass held on by surface tension. So the details wasn't that washed out, but also it was not very well covered after all, and not handling safe in that state.
Mineways.com has been getting a lot of well deserved attention lately. In short it's an excellent Minecraft export tool, tailored towards Shapeways printing. While us DIY enthusiasts can't do full colour prints (yet), Mineways is still an excellent tool for exporting models for home 3D printing, and it's quite user friendly compared to certain other attempts.
Here's a few videos where I show my first attempt to do a large print of a landscape, and then a smaller print. If you have some experience with WorldEdit and 3D printing, it should be pretty straight forward to follow.
This post is a detailed tutorial on how to use Mineways to export printable stl files for a RepRap or derivative machines. The details are from a large-ish landscape model, but the principle is the same for all types of exports.
As some people are having problems with this, I present a small tutorial, as I believe I have found both an explanation and a solution. Inkscape is a wonderful program, and teamed up with OpenSCAD it makes a lot of cool stuff possible.
It works with Inkscape 0.47 and 0.48 without no extra plugins.
Update 2012.06.01 : Changed code on step 9 to use the preferred child import(). Update 2012.09.16 : Added information about "add nodes" on step 6. Update 2012.10.09 : Added information about "flatten beziers" on step 6. Thanks to zeptomoon for the suggestion!
If you don't want to read my ramblings, the trick is easy: Make all the curved segments lines before you export to dxf.
Now, commence indepth tutorial:
1 First off, let's make a simple object, like this ellipse.
Note the square and round handles on the object, which indicates this is an .svg style object which you can modify according to the specific rules of said object.
2 This is of course no good, as OpenSCAD / dxf can't read this format. What we need to do is convert it to a path. [Shift+Ctrl+C]
3 Select the node tool [N], and notice how the handles on the object now look like gray squares. This indicates we now have a path.
4 Drag-select, or press [Ctrl+A] to select every node. With the nodes selected, notice how the handles changed again. The lines with spheres at the end tells us the segments between the nodes are curved. (Try fiddling with the points if you like).
This, again, is no good for the standard .dxf plugin in Inkscape, which only exports straight lines. (See point 8).
5 With every node selected, press the indicated button to "Make selected segment lines".
The lines with spheres on the handles are gone, so we now have only straight lines between the nodes. This would work, but doesn't look very smooth, does it? Undo your last action and continue to next point in the tutorial, where you learn to do it the right way. (Sorry about that).
6 With every node selected, initialize some mouseclicking action on the indicated button "Insert new nodes into selected segments".
This, well, inserts new nodes into selected segments, following the curve.
Press a few times if you want a smoother object, but don't overdo it now, you hear?
You could also use "Extensions - Modify Path - Add Nodes" for dense, even distribution of nodes all over complex parts.
Even better is to use "Extensions - Modify Path - Flatten Beziers", which will only add nodes at curved areas, resulting in less useless nodes. A value of 0.3 is a good value to start with. Thanks to zeptomoon for the suggestion!
7 Feel free to once more click "Make selected segment lines".
This looks much better. The lines are straight, but due to the sheer numbers, they simulate a curve! Victory!
You can of course select only part of the nodes, if you only want part of the model smooth.
8 Now save the file as "test.dxf". You will need to select "Desktop Cutting Plotter (R13)" in the type drop down box.
Notice the help tells us we can only export certain elements. What we have done now is create only lowpolylines, which exports beautifully.
9 Start up OpenSCAD and use the following code to open up the file. (You need to put the .scad and .dxf file in the same directory).
linear_extrude(height = 10) import("test.dxf");
There you go! Enjoy your Inkscape paths in OpenSCAD.
10 This works fine with any objects, advanced or not. Just remember to union the different paths.
Also note the part "Rap" is not just white text, it's a proper hole made with difference.
You can of course export several .dxf files and combine them in OpenSCAD if you need different height on some parts.
It can sometimes be difficult work with the .dxf file in OpenSCAD, as Inkscape exports the entire page, and it can be a bit tricky to locate where the object are. I recommend you select everything, go to Document Properties [Shift+Ctrl+D] and "Fit page to selection". Edit: See below. The problem is a bit difficult to explain, but you'll understand it once you have experienced it.
Take care not to overwrite your original .svg file if you want to be able to edit things later. It's much easier to work with objects than paths.
Edit 16.09.2011: I have found it easier to align the objects to point 0x0 (the bottom left corner of the page in Inkscape) and not center the object in OpenSCAD. Then you can easily stack several .dxf files in different heights.
Now go forth and make something awesome! Remember to share your .svg files on thingiverse, to go with the .scad files!
I hope this helped, and clarified some things. If you have further questions or suggestions, feel free to comment.
