Towlie, a homemade kitchen towel holder.

This is something I was looking for some time ago and could not find one from any shops. A simple hook that will hold the kitchen towel right where I need it.

I used to keep the towel folded atop of the cupboard door, but it tends to slide of and drop to floor. With this simple hook, the towel won't fall, but it's easy to access. And when printed with clear PLA it next to invisible.

As usual, 3D design is made with Sketchup program and then converted to STL with exporter-plugin.

Apparently I entirely forgot to make post of my Towlie-design. So I will backdate this to around the time I uploaded the files to Thingiverse. I originally designed this thingy at 10th Jan 2012 but uploaded it at 14th.

Original design files available, with free CC lisense. Just download and print as many as you need. I'd like to hear your feedback of this design, does it work or not, does it need any modifications or is it good just as it is?

Hello cookie, cookie cutter tested and working.

Never had I guessed how much time it takes to design and make two part cookie cutter. But at least the first version is done and tested.

As you can see I now have some cookies cooling down. I'll think I leave the decorations for tomorrow. So, it you can't tell what the cookies are, it'll be revelated at 19th.

About the printer, I think I got it fixed for now. One can't expect home made equipment to have same uptime and reliability as fifty-hundred times more expensive office machines. At them moment it works nicely, but I need to check some technical details and its likely there will be some hardware tinkering ahead.

Addendum (19th) : Well, the printer was kind enough to make those cutters ok, but the next bigger print failed (at early stage)... Ah well.. repairs are part of the learning process here.
 

Cookie cutter, how to design in 3D

After publishing my first Finnish blog post about 3d printing a friend of mine asked, how about making some personal cookie cutters for Xmas. Especially she was looking for some Lovecraftian style cutters, that are not available on any regular stores. My drawing skills aren't really up to reach that kind art, but I'll at least will try to explain a simple way to make them in case someone is willing to provide the 2D drawing.


Open the 3d cad program you intend to use and draw/trace the intended cookie figure on X-Y plane as an continuous 2d line. While drawing, also be sure that the shape is correct size and stays strictly at the X-Y plane. Mine is kinda primitive Tree-shape..

Next. Perpendicular to that, draw the wanted profile of the cookie cutter. Usually the cutting edge of object is made quite thin, and the handling edge has some widening.





With these two shapes ready, use the Follow-me too. With the Follow-me tool, wonder around the original shape so it becomes 3d object with desired outline and profile. At this point one could consider changing the design for making it a bit more user friendly, like rounding the corners and making the holding area wider.
 
When you are happy with the shape, save the draving and export it as an STL file for further processing.






Use the printer software for slicing the 3d object and create Gcode file for the printer. Before continuing with the printing, it's usually good to preview the print at the preview window. If everything is fine, set desired options and print.

And with some 10-20 minutes later you have your own freshly printed cookie cutter, or.. as in my case happened. you'll realize that you'll need to make some adjustments to model before it's really any use in real world.

And the first version of my cookie cutter is there, I'll need to wait it to cool down before lifting it from the build bed. PLA is quite soft while warm, so one must be careful not to bend this kind of thin walled objects.

For next one I think I'd thicken the walls somewhat, also rounding the sharp corners could be good idea.



PS: As a final note. I have not done any official check concerning food-safety of these plastics used with 3d printers, so I don't assume it would be legal to start selling these cutters for people. I would really like to know if anyone has done the research. The plastic in question is PLA 4043D ...

Update: I have made normal speed recording of the printing this object. It's currently uploading to Youtube, so it should be available someday at this address: http://youtu.be/Krs07ptgkmc

Designing freestanding spool holder

Freestanding filament spool holder

Since I got this 2.2Kg spool of natural PLA, it's been clear to me that I need to have sone kind of spool holder. With small printer like Huxley there is really no point trying to bolt large filament spool at the side. And while there were many ideas at the Thingverse, none of them was what I was looking for.

So, I felt need to design and print one of my own. I knew that by keeping it simple, I'll need just some plastic parts alongside bearings + 20cm threaded rod.

First I made the A-like shape with the3d program. Extruded it to be 5 millimeters thick and made a hole for connecting rod. The length of legs is limited by printer's bed size, and thus the entire object must fit under 14*14 centimeter area.

Originally I hoped the leg-parts alone would be enough, but this spool was after all a bit too large so I had to design those raiser feet under it. Having larger printer would have done the trick, but I'm not going to build bigger one just yet. :-)

This spool makes my Huxy look so tiny

Now the spool stands nicely right next to Huxley. Time will tell, if the leg parts were made sturdy enough. I think they will hold the weight quite nicely.
 
All design files are freely available at http://www.thingiverse.com/thing:14329

Messing with Meshes (sorry a bit complex stuff)

Hello, I have been busy trying to understand terms like 2-manifold, water tightness, normals and  meshes.

More often than not, when you find or design nice looking 3d object that you'd like to print, while the object is good enough for visual viewing,  it's not for 3d-printing. Many 3d programs (including Sketchup) are not accurate on how to define the objects. And while these issues are not important on screen viewing, the manufacturing expects better qualilty and consistency.

In principle making your own 3d object is simple 3 step process:

1. You design object at right size on 3D program and save it as .STL
2. Using slicing program (Skeinforge, SFACT, Slic3r) generate the G-code file 
3. Use Pronterface to upload G-code to printer and print.

But... That happens so easily only on occasion. Usually there are some problems which need to be addressed during the process. Sometimes there are problems that don't prevent printing, but will cause uncertainty of the result, other problems can prevent printing the object entirely. Other can hinder later modification of the objects.

To put it simply(*), the Skener/slicer will need and object that is 2-manifold to create printable G-code. If the STL file has any holes or other mistakes (like duplicated faces) the slicer program has to make some kind of guesswork of the most likely object the STL file is supposed to represent. Quite often this result is similar to what was intended, but there may well be some nasty surprises.


Also, while the OpenSCAD program I used to scale objects on my earlier Blog entry does import stl-objects that aren't 100% correct, it can't render them properly nor can it repair them for saving. So the OpenSCAD scaling trick works only if the original object is valid 2-manifold.

At the moment I'm trying to learn how to use MeshLab . It's quite large and complex program intended to be able evaluate, simplily and fix these kid of issues on various file formats. At the moment I can't say that I have had much success with it, but I'd expect this take some time.






(*) For nonsimply answer.. It takes a lot of university level mathematics to go trough all the details and issues of open and closed surfaces, and I'm not going into there.

Next step, the 3d design software

As fun as slicing and printing various pre-designed object is, the real reason for having your own 3D machine is to design and make your own parts. And for that, I have started to download and install various opensource/freeware 3D cad softwares, for testing and evaluation. I have decided to test these three first.


First of them is Google Sketchup . I have met this software before, and have been occasionally using older versions. It's development began of making 3D buildings at Google Earth, since then it's been grown more versatile software and it can be used to make many kind of objects. Negative side is the lack of direct .STL exporting, but there are at least 3 different export modules available for free. Positive side is that it's well maintained, has plenty of manuals and tutorials so learning goes fast.

Secondly is OpenSCAD . It's a bit strange program for anyone expecting typical Cad-package, since all objects are made buy defining the shapes on text scripting. Good part is direct STL support and wide acceptance on RepRap community. For example source files of the Emaker Huxley printer I have are released on OpenScad format. I'm not saying it's a bad program, but just warning that at the first time it may feel a bit odd, since the approach is more like programming than3D designing.

Third on I have installed is FreeCAD   This is totally unknown program for me at the moment, so it's likely be the last of these three to test. Can't really tell much of it at the moment, but I know some people do use it for 3d object making.


Other free software I could install include Blender, but it's so big and I'm trying to find something relatively simple and nimble program.  There are also lot's of commercial 3D cad/cam packages (like Soldworks, Mastercam etc), but none of those are within reasonable budget for me. I have also found some potentially interesting free-to-use cloud based 3d tools, but so far none of them had what I wanted.

As a last note I'll add one pic, a partial collection of items I printed but have not shown before. All of these item's are either part of the Huxley or freely downloadable from Thingverse.