Wednesday 28 December 2011

New year coming, new directions to blog (Meta, Video)

Happy holidays.. It's meta-time just before new year hit's all of us. 

Now, I think that it's about to give up posting short notes of various 3d printed items. After all, I've been making them quite a while, and even though I have lost count of the trinkets been made, I do know that I have spent over two kilos Pla-printing material. So what I was saying, is that novelty of the printing just for printing's sake is gone, and from now on I'll be using it as a tool for other projects. Projects that have been on back-burner due this new printer.

But before giving up entirely I decided to write a bit intro of couple items.

This on is nice 20 mm wide and cable guide made from 12 printed pieces. I'm planing to install to my Huxley printer so that it'll protect those heated bed wires. The main idea is to stop the cables connections breaking apart from stress caused platform movement during printing.

And: What's 3D printing without some shapes that are next to impossible manufacture with other types of machinery?

This Alien Egg, an abstract design, that is hollow inside. It weights very little compared to it's size and strength.



Of 3d design.. I'll get to the point, if there ever was a point. Point reminding me that I'll need to widen the coverage of the blog. During these first couple months (7 weeks)  of blog/vlog I have made just one teardown video, no reviews, and only electronics related stuff has been about me soldering the electronics board of the Printer.

So what I have at the list.. Some talk and examples about Polymorph, yes it's plastic too, but somewhat different material. Reviews of couple nice and useful electronics tools/meters. Some ideas of electronics, using old and new chips and components. Also some work with lasers and combining various building technics. Fixing various items and hacking something new from those that can't be repaired to original use.

And.. also more videos.. I think I'll skip the numbering and credit screens from videos that ain't so essential. Like that Alien Egg printing video, that lasts about 50 minutes, and has no texts nor voice over.  It's currently uploading to Youtube, and should become available at:

http://youtu.be/fYAaWnk5hgs




Tuesday 20 December 2011

A fix, I hope

Two of these.. 

I have finally decided to start making new parts in purpose of fixing the on/off issue of this printer. With Bowden type extruder, there is always a risk of the bowden-tube been too stretchy or getting lose.

At Emaker Huxley, this 3mm PTFE tube is attached with an Pneumatic connector, which is nice and quick way, and does usually work reliably enough.

Unfortunately that didn't seems to be case with my machine. I am not sure if it's due variance at parts or have I done something wrong while building the machine.
with four nuts+bolts and two cable ties

Earlier I have tried some alternative fixings, like glue and heatshrirk tube. Unfortunately the PTFE (best known with brand name Teflon) tube is extremely slippery so making solid fix is kinda hard.

I do hope this one works,.. There is room for improvements, in case someone is interested. All the design files are available at http://www.thingiverse.com/thing:14854


Monday 19 December 2011

Time to reveal our mystery cookies..

So here they are, with sugar coating on top. I do hope they are bit easier to recognise, the pressed pattern did lose some shape while baking, but frosting should help.

For the upcoming years, I really need to think about making that frosting-extruder -module for my 3d-printer.

Hello Chulhu cutter is my own design, the DrWho relarted files are found from Thingiverse site.

Now I have to find some use for the excess frosting. what it could be used for? ... except of course making more cookies?

Note: This design is freely available at http://www.thingiverse.com/thing:14920


Sunday 18 December 2011

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.
 

Saturday 17 December 2011

Zenithink ZT-180 ePad teardown, Video #6

This time I decided to make a quick teardown video of Zenithink ZT-180 ePad I recently purchased secondhanded. It's amazingly easy to open as soon as you know the trick. I have not yet bothered taking the logic board out since all essentials are shown as is. There are some oddities in this machine, like using cheap painters masking tape to cover and fix parts, but that may well be left there by some earlier user.




Meta: I have not lately been making these 3d-printing related updates. I have been occupied with other activities, so no new cookie cutters designed/printed yet.  I also need to do some repairs for the printer, there's a known weakness on one part and it hinders the printing process. Perhaps I'll make a video of that too while I'll try to think best feasible way to fix issue.


Monday 12 December 2011

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

Thursday 8 December 2011

First fix, video #4

This video is recorded at 30th of November. Like I then mentioned at Repairs and reshoot -post, I managed to mess with the X-drive belt while printing the oversized object. I fixed belt at the same night, but have not edited the video until today. While I'm writing this the video is rendering and I'll link it here as soon as it is available at Youtube.


All in all, the fix was easy and took me about 15 minutes. I might have been able to do it a bit faster if the camera has not been in way at a time. So far the problem has not repeated itself. I didn't mention it on the video, but I also added a dash of glue to the belt end. I do hope it'll help it to keep well put.

I have also renamed posts which have video files embedded. I hope it'll make finding the clips easier.

Tuesday 6 December 2011

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




Monday 5 December 2011

Video #1, Intro

Ok, so it's out there, in public, finally. At youtube, amongs millons of other videos.


Saturday 3 December 2011

A small object to make..

As mentioned earlier I got this small replacement part to design and print. It is an fixture to hold window blinds adjustment rod neatly. This definitely ain't complex part and I know that these are sold at stores. But as an example of a home made thingy.. It's not bad at all..

My part at Sketchup
It took me some time to get the 3d shape in a form I'd like since I'm no expert on 3d cad work. Also I needed to fix the model couple times as the exported stl -file was declared to be non-printable. For printing I used clear PLA so I had to paint the part. Painting itself was not difficult, a friend of mine has nice set of miniature paints and they seem to stick nicely to this kind of plastic.

15 * 20 mm part, ready to use
During the design process I noticed that by altering the shape somewhat I could make this part much more solid, but I decided to keep changes as small as possible. If it holds, good. If it breaks, well, then it's time to make some modifications to design.

Addendum: I forgot to add the cad files.. Both Sketchup design and stl-export are freely available at:
http://www.thingiverse.com/thing:14169

Friday 2 December 2011

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.