One of the first open-source, hobbyist-grade Fused Deposition Modeling (FDM) 3D printers was the RepRap.  Those originally responsible for the project decided that one of the important features of the design was that it be able to produce most of the mechanical parts used to build another copy of itself.  Since it's initial start in 2005, has done well to achieve that goal, and users are now happily creating 3D objects, along with parts to build new RepRaps.  There is even a new RepRap machine, called the v2.0 "Mendel", with improved design and capabilities.

I understand that there are many ways to measure success.  I think that the RepRap has been successful in increasing awareness of hobbyist 3D printing.  The project has also been successful in designing a machine that can indeed make most of the parts for itself.  Where I think it has not been successful is that more people don't have them, and there just doesn't seem to be an enthusiastic "buzz" for them.

I think that the novel idea of a self-replicating machine, is actually the machine's biggest downfall.  It isn't that self-replication isn't a noble cause, it's simply that it isn't a very pragmatic one, especially at this stage in the game.

My initial impression was that being able to create its own parts seemed like a great plan.  What better way to spread 3D printing than my letting the enthusiasts get their buddies hooked, right?  The inherent problem is one of momentum, a "chicken or the egg" effect.

Right now 3D printing is a small niche hobby.  The technology is only now becoming mature at a commercial level, and is in its infancy at a hobbyist level.  DIY 3D printers do not yet have the benefit of a support material, and are not yet designed to use one.  A support material is a second type of material, besides molten plastic, that the machine can extrude.  It is used to build up a support underneath a hollow, concave, or overhanging part of the model.  The support material is usually soluble in something, and can be dissolved away at the end of the process, leaving only the plastic undercut of the model.

Because DIY 3D printing is so new, and commercial 3D printing is so expensive, it's not very prevalent yet.  I compare it to laser printers 15 years ago.  Most people with an interest in technological toys probably know what 3D printers are, the public has a vague idea they exist, and most people probably know some (or know someone who knows someone) that works at a company that has one.  There are probably no more than a couple thousand DIY 3D printers in the world today.

So the paradox is, "If 3D printers are very uncommon and rare currently, why try to break into the market with a new 3D printer that requires the use of one to build?"  It didn't take long for that to strike me.  I realize that it is not impossible to get your parts made so that you can build one.  But why would you want to intentionally put an obstacle up for new users?

I would have preferred not to use such a cliche term as "barrier to entry", but I thought it was a very fitting description of what the RepRap designers established.  Think of all the basic capabilities that a weekend DIY'er has, and ask yourself if getting 3D models printed on a 3D printer is one of them.  Of course it isn't.

I will admit that I don't own a RepRap, but after looking at the pictures, it seems like these elusive "printed" parts are nothing more than simple blocks, with a couple holes and grooves cut in them, used to connect metal rods/tubes together.  So why not design the first RepRap to be made out of off-the-shelf materials like inexpensive blocks of HDPE, or MDF?  If it had been designed to use a "better" material, anyone with a saw and a power drill could have built one in their garage.

In fact, after realizing this was an issue at some point, the RepRap community coined a new term... RepStrap.  A RepStrap, being a pun on the term "bootstrap", is a machine that is cobbled together from whatever you have, so that you can actually fabricate the parts necessary to build your RepRap.  Great, build two machines so that you can have one!  There couldn't be a more appropriate use of the phrase "two steps forward, one step back".  And so the barrier to entry is raised once again.

I want to take a moment to convey that I do understand that there are reasons some people would want it this way.  I think there are a couple types of people dabbling in 3D printing:

• The "It's a journey, not a destination" type: There will be people that enjoy the 3D printing hobby strictly as an activity in itself.  The act of building the machines, improving their design, and contributing to the community are the hobby.  These people will not care as much if they have to build one machine, to build a second, and if the barrier to entry is very high.  They'll move the mountain, one shovel full of dirt at a time.
• The "Imagine what I can do with a 3D printer" type: These type of people will want a very low barrier to entry, and will be less enthusiastic about having to do lots of research and learning, expend lots of resources, or overcome lots of obstacles to own the 3D printer.  For them, the hobby is much more about what they can do with the tool.

These two types fall on a spectrum, and you're going to find those that sway to either side, or land in the middle.  I would say, though, that most people lean more toward the second type.  If the first type was most popular, we'd have an internet full of thousands of 3D printer designs, competing to be top dog.

If things had gone differently perhaps, this story could have ended with tens of thousands of DIY'ers with 3D printers today.  But that wasn't how the cards played.

Instead MakerBot, has stolen the show completely, in less that a year on the scene.  MakerBot's primary product is the CupCakeCNC.  The CupCakeCNC is a complete DIY 3D printer kit, costing less than $750, with a build area of 4"x4"x6".

By now, MakerBot has sold about 1000 kits.  That means in less than one year, MakerBot has eclipsed what RepRap couldn't do in 4+.  And how did they do it?  Simple, they removed the barriers to entry.  All you have to do is buy a kit, and you'll be printing things out after just a few hours of assembly.  From there, you can grow your knowledge, and experiment with new parts and techniques, but in a controlled fashion - one change at a time.

MakerBots were in such high demand during this past (first) year of offering, that the company couldn't keep up with production.  Under the clever disguise of the term "distributed manufacturing", MakerBot Industries will pay YOU to help them make parts to meet demand!

And there are more entrants coming.  Patrick Hood-Daniel, a prominent builder in the DIY CNC community, and author of the site BuildYourCNC, recently announced that he will be releasing a similary priced, similarly sized FDM 3D printer, that will best MakerBot.  He calls the machine WhiteAnt, and will be releasing further details soon.

These clever offerings are finally doing what is necessary to get the 3D printer movement moving.