Pinball hacking and personal fabrication
I consider that building a pinball machine at home during these last 4 years or so has been a strongly symbolic act. It has started as a need to materialize a proof of concept of a clever hack I once figured out was possible based on the knowledge I had acquired after spending lots of time and effort reverse engineering an old pinball simulation game. The proof of concept was not very hard and indeed the hack is already proven through some early experiments. But a corollary of this discovery was pretty obvious: I would have to build the real version of Pinball Fantasies sooner or later.
So I felt challenged and started to build it, just for fun. I was trying to do something that I had never done before and that I hadn't even heard of other people who had done similar projects. Building a homebrew pinball machine sounded to me like a very ambitious project. Nowadays I am aware that I am not the only geek working on custom pinball development (there is perhaps half a dozen other people in the world having fun with it such as Jeri Ellsworth), but I didn't know about that at the beginning of the project and so I felt alone and obliged to come up with my own solutions to overcome each of the challenges involved in the execution of the project.
Then, gradually, I started to perceive some interesting relations between this project and my previous (software-only) ones. I had been fighting for software freedom and access to knowledge for some time and now some of my practices from the software world were being replicated in the physical construction of the pinball machine. I had decided to publish every details of the project (including lots of photos and source code) because I felt that I should encourage other people to build things also. I was also refusing to use proprietary software and based on the same principles I was avoiding fabrication processes that I did not fully understand. For instance, I was not happy about relying on professional laser cuter services to build some of the acrylic parts of the machine. I wanted to cut the parts in a homebrew CNC machine that was designed and built by a friend that I met through one of the brazilian pinball club mailing lists. I have only used the professional laser service because my friend's machine was broken and he did not seem to have enough time to fix it.
I have also decided to use the Arduino controller board and it was a good reason for me to learn more about microcontrollers. I have then bought some dot-matrix-display modules and had to help a niche community of Arduino hackers to adapt code for controlling these displays (in my specific case, I needed to control 7 of these simultaneously). I have even discovered Inkscape while I was looking for a CAD software to draw blueprints of the machine (Inkscape is not CAD, but I stumbled upon it during the search). I quickly fell in love with it. I have become an Inkscape developer and this is one of the reasons why the pinball project was neglected during some long periods of several months with practically no pinball hacking and lots of SVG renderer implementation efforts.
But what motivates me to tell this story is that recently I have become aware of this trend of personal fabrication technologies. Projects like the RepRap and the CupCake CNC are bringing the hackability of free software to physical things. And after reading the articles about it on Make magazine, I've decided to try to use it on my pinball project. I think that it is a practice totally compatible with my feeling of a need of better understanding the processes of fabrication, instead of simply achieving the desired results. It is a matter of getting more and more autonomy to create and build things and it is also about feeling more empowered by the knowledge acquired.
Some time ago I felt the need of having a 3d model of the machine in order to make some design decisions. For example, to have a better notion of the space available for some pinball parts in the playfield and to decide on placement of some screws. But I had almost no knowledge of CAD software and for some reasons that would require me to tell another long story (perhaps I can talk about it in a future blog post), I got involved in GNU LibreDWG, which consumed me another bunch of months with no pinball hacking again :-P I have then tried to make 3d models of some pinball parts and then found this guy who had done it also for some commonly used parts and had made his CAD files available online.
My conclusion to this blog post is that I think it would be awesome for the pinball hacking hobby if we could gather more interested people to make 3d models of pinball parts and share them in some place like thingiverse.com and then it would be interesting to see people building such parts using homebrew 3d printers like the RepRap. I think that my first attempt at that will be trying to replicate bumper caps to look like the ones depicted in the artwork of the original version of the Pinball Fantasies game. I have tried to improvise bumper caps using chocolate mousse cups once and it looked great, but it was slightly larger than the ideal size and those wouldn't fit well in the layout of the PARTYland playfield I am building. I did not have a good solution to this bumper cap issue until now. It seems like RepRaps will be very useful for my pinball hacking fun.
I must just take care of not spending some additional months focused on building my own RepRap printer... I know that there is a big chance of it happening, given my usual behaviour, though :-P
A yellow bumper cap from modern machines:
My "chocolate mousse cup" bumper caps: