Case for a FM-radio (Velleman MK194)

I have a MK194 radio kit from Velleman and turned it into a radio some  time ago. The radio looks pretty cool with all the electronic components visible but the wooden case was awful. I therefore decided to build a new case for it. Of course I want to use my Hephestos 2 printer from BQ to make this case.

First I designed a case in FreeCAD. I use FreeCAD for a couple of weeks now, together with OpenScad, but this is the first design with multiple parts that I create with it. After several iterations I finally decided to have a design consisting of three parts. A box, a support plate for the radio PCB and a lid. The radio fits into the support and the lid which are then screwed onto the box.

Design for the radio case made with FreeCAD consisting of three parts (the red part just represents the MK194 PCB). I made a nice radius on the lid and the MK194 fits nicely between the support and the lid.

I think the radio looks really nice now much better than the wooden case at least. I'm getting the hang of FreeCAD. The learning curve is steeper than OpenScad's but it is worth it. Creating a more complex design is just faster with FreeCAD than with OpenScad (at least for me).
Here are the .stl files:

• box
• support plate
• lid

My FM-radio on my electronics workbench.

Blogger vs WordPress

My sister asked me to create a website for her business. In all honesty, it's been some time since I last made a website so I did some research before I started. I quickly found out that WordPress is now the dominating platform or content management system (CMS) as it is called. It's also completely open source (GPL license) which is a big bonus for me. It therefore didn't took me long to decide to use WordPress for the website.

While working with WordPress I was impressed by it's the ease of use and the huge number of themes. Also the support on the internet is excellent. So I began asking myself if I should move my blog from Blogger to WordPress.

I use Blogger for over a year and, although is was a great way to start blogging, I have some doubts about the platform. The user interface is a bit of a mess, especially if you want to do more advanced stuff. Yes, you can import a theme, or even create your own but my guess is that most people don't know how to do it. These options are hidden somewhere deep in the Blogger interface.

More importantly the Blogger website is owned by Google. Even worse Google also owns the content of your website. If Google decides to stop the Blogger.com service or if Google thinks that your website is in violation with their content policy and take your blog down you're out of luck. WordPress.org doesn't suffer from this. You download the WordPress software onto your server and you (not Google) are in control of every aspect of your blog.

It appears to me that the Blogger.com doesn't get a lot of attention from Google. This last year I haven't seen a major overhaul or new themes from Blogger.com. In fact some features are being removed. The blog posts on Blogger Buzz (the blog of Blogger.com) are sparse,  which isn't a good sign.

For the time being I will use both Blogger.com and WordPress. Maybe some annoying features of WordPress will pop-up. Also it will be interesting to compare the page views on both bogs. In a couple of months I'll decide which blog platform I'll prefer but as it stands now it probably will be WordPress.

What to make for Valentine's day?

What to make for Valentine's day? A bare perfboard with a Valentine's chaser (basically a 555-chip, 4017 decade counter and a handful of leds) doesn't look too impressive. That's why I made this heart shaped wooden box with a laser cutter. Both printboard and battery fit nicely into the box. Three bolts, nuts and washers to finish the job.

The file for the laser cutter (.svg) can be found here.

And here is a 3d printer file (.stl) of a little dock for the heart.

Assembling a 3D printer kit (BQ Hephestos 2)

Introduction

While making my projects like the Darth Vader chest box 2.0 I use the local fablab a lot, especially the laser cutter and the 3D printer. It was a bit boring to wait for the 3D print to finish (laser cutting is typically much faster) with not much else to do at the fablab. I therefore decided to buy my own 3D printer. I choose for the BQ Hephestos 2, a sturdy Prusa i3 all metal printer that comes in a kit.

After a few days the BQ printer arrived in a huge box. The filament (PLA and Filaflex) that I ordered also arrived together with BuildTak, a thin plastic sheet that adheres to the printbed and should provide a better adherence of the 3D object to the bed. According to sources online it should take 2-3 hours to build the Hephestos 2. I have no experience with building 3D printers so I figured it would take me longer.

Assembly

The assembly guide that comes with the Hephestos 2 is very good and all parts in the box are clearly tagged.  Therefore building it is not very hard. I found it comparable to building a PC. The difficult part was the cable management. Like a PC there are lots of cables and they all need to have the proper length and you need to connect them properly. Again the assembly guide is a great help here. Eventually it took me six hours to build the kit. Not too bad for my first 3D printer. 

Printing

My first prints with the 3D printer were disastrous. I tried the PLA first because this is the easiest material to print. The object came loose from the glass print bed while being printed. Next I tried BuildTak on my glass print bed. Alas, same result. Somewhat frustrated I bought some Pritt and applied it on the BuildTak surface. After that all objects adhered perfectly to the printbed in fact it took me some effort to release the object. In fact when I printed a large symmetrical object one end was on the pritt covered surface and the other was not. The part that was not on the pritt had severe warping issues while the other part was great.

Conclusion

The Hephestos 2 doesn't disappoint. For someone with little experience with 3D printers assembling it is relatively easy. The instructions in the manual are excellent and all the components are first class. BQ developed their own extruder and electronics (Zum Mega 3D board). Operating the Hephestos 2 is also easy. Removing filament from the extruder, inserting new filament, calibrating and printing is all made easy with good software and navigation. Is their nothing bad to say about the Hephestos 2? Well, the kit costs 850 euro (including 21% VAT) and for this price it doesn't even have a heated bed. That's a steep price compared to the $300 Chinese Prusa i3's. On the other hand, reviews on the internet suggest that these Chinese clones come with cheap (or even broken) parts and lacking manuals.

The first stages of the assembly with the X,Y, Z axis finished. 

Printbed, display and Zum Mega 3D board installed.

Better view of the Zum Mega 3D board which looks very nice.

After finishing the assembly switching on the Hephestos 2 for the first time

First print with the Hephestos 2 was a disaster due to lack of adherence of the PLA to the glass printbed.

BuildTak sheet on the printbed and a view of the extruder.

Pritt on the printbed solved the adherence problems.