Erik's Blog: Discussing open source innovation, personal fabrication and a ...

There are now an estimated 1000+ RepRappers! These people are actively building on their own instance of the Open Source Replicating 3D printer.

When I started working on my RepRap in May 2008 (8 months ago). At that time there were about 20 people actively involved in the project and only a handful of people had a working machine. Because I had a lot of spare time, about a month later, I was also part of this group. When I had the proof of concept build and made some 3D prints, I started changing the machine's electronics. Then, I had vowed to finish my bachelors degree first, so I had considerably less time for the RepRap, except for giving some presentations and workshops. Meanwhile, the rapid pace of growth has not stopped!


I have always given a factor two exponential growth as an example. I used to say: for each person with a RepRap that enables another person to make a RepRap by printing the plastic parts for him, you will see a doubling of the amount of RepRaps. But now it seems like a 50-fold increase in three quarters of a year. If you assume the growth is purely exponential, this would mean that it's an annual growth of 50^(4/3) = 184.2. This is an estimated 18420% increase of RepRappers in a single year! Of course, the amount of people with a working machine will lag behind that. It will range from 1 month, probably up to a year. But even if 'lead times' were an entire year on average, the amount of RepRappers will still be staggering in a couple of years!

If we take a conservative amount of growth, e.g. 1000% growth annually and one year lead time, there will be a million people with a production RepRap within 4 years! This is with the conservative estimate based on an exponential effect. With the 18420% growth (which is also unbelievable to me, I must admit), this is 1.3 years before there are 1 million RepRappers. My gut feeling says that an annual growth factor of 20 is realistic. In this case it would take less than 2 years and 4 months before there are a million RepRappers, while only 6 months later, there will be twenty million (LOG(10,000,000/1000)/LOG(20)=in 3.07 years), and 400 million within 4 years.

It is always hard to predict a trend that is in its early development. Yet the system dynamics of this particular case are a strong case for exponential growth. The drivers behind this growth are (to name a few):
1. Word of mouth, determined by amount of RepRappers
2. Evolution of the design, determined by the amount of skillful people attracted to develop and improve the RepRap
3. More people with a RepRap, more readily printable objects on the internet.
4. More RepRappers, more infrastructure (sites like thingiverse), sponsors, more buying power of RepRap stores
5. More RepRappers, more forks (mobile RepRap, large-scale RepRaps) and extensions of the concept RepRap to an entire replicating lab (RepLab). More forks also means that there will be more paths towards a RepRap (a.k.a. RepStraps). I've seen RepStrap parts cut from steel, acrylic, plywood. I've seen them built from meccano, lego and fishertechnik. There are now laser-cut acrylic RepRaps, PlyRap's, LegoRap's, RepScrap's, Fishertechnik RepStraps, and many more to come. Also, the RepRap is able to do light milling work, extrude metals, various pastes, chocolate, etc. Also, rudimentary scanning of 3D objects has been done!
6. Maturization of documentation, larger group giving support to new users.
7. Open source is extending more and more into the hardware domain. This allows for interesting things to come, since it the RepRap can provide the body of all sorts of machines, while Arduino's and other open source electronics provide the brain. This will provide a nice symbiosis.
8. Businesses around 3D products will emerge. This will create spillovers, improvements to the machine. It will also draw capital into the infrastructure besides all the individual investments done by RepRappers (totalling +200,000 dollars last year).

I argue that besides just Metcalfe's law that describes network effects, there are many more drivers behind this growth, but it is also much more complex. But most importantly, the strength of many drivers are linked to the scale of the RepRap user-base. This means that the rate of growth is determined by the scale of the user-base, which is increasing. There are of course diseconomies of scale, market saturation points, etc. Diseconomies, such as that the design becomes more complex (in order to produce better quality), fewer people can still contribute to the design. I think the core technology will become privileged to a group of specialists, but there is so much more to a project than its core technology. People can do a variety of things to help such a project prosper. And each person himself knows what he is best at (far better than any HRM department). About market saturation: I argue that as the machine evolves to become easier to assemble and still more powerful, new and wider markets will start adopting this innovation. Also, if there's more infrastructure supporting the growth of RepRap, it will become easier to acquire production-ready sub-assemblies and eventually entire machines. I really think that growth is not unlimited (there are certainly resource limitations), but that it still is exponential and that the growth rate is high. This particular machine has solved a major scalability issue by also being its own infrastructure. Perhaps one of the few competitors that could arise and become a viable substitute is also a replicating machine. Yet we will still see a democratization of manufacturing, since there will be no scarcity of these machines. If there's no scarcity of machines that can produce an ever growing amount of useful items, there will be no scarcity of useful items, given materials stay in a closed loop (cradle to cradle, which is within reach for RepRap).

Each of these effects can be seen as positive feedback loops (also know as 'snowball effect'). Besides that there are some trends that are exogenous but still are drivers growing in power:
1. Growing popularity and Open Source and Creative Commons are doing well and becoming better-known!
2. DIY trend (instructables, Make Magazine very popular)
3. Long tail: Demand for mass customized products. More and more means to reach the long tail market with your own objects.
4. A need and desire for sustainable living. RepRap provides a big opportunity there (linked article in Dutch).

I wonder where we will be next year. I'll surely make another post about it around 1 january 2010!

"Taking over the world,
one piece of plastic at a time..."