Your right. There are 22 bearings total. However, they are all cheap inline skate bearings except for the 2 on the tool. (Note: my Printrbot has 6 rods, 10 linear bearings, 2 threaded rods, and 5 bearings.)
It would be very hard to make without a 3D printer. Luckily, I have a 3D printer. (You would have to make/get a RepStrap to be able to make this RepRap. Standard RepRap plans are usually hard to make without a RepRap. I am sure I could do a redesign with only garage tools in mind.) Also, right know there are only 9 unique parts. Everything has radial symmetry. Additionally, I could get rid of 6 of the bearings between the lower arms and the upper arms. A simple pin connection would be more than sufficient. (I am going to spend the extra $6 for less friction and symmetry.) That would bring the total to 16 bearings. That is exactly how many bearings (linear and radial) that a Printrbot has.
I may be biased but I would say the design is simpler than the other RepRaps. (I am psuedo-measuring this with part count, part complexity, plastic volume, assembly time, etc.) The firmware, however, will not be so simple but electrons are cheap.
It would be very hard to make without a 3D printer. Luckily, I have a 3D printer. (You would have to make/get a RepStrap to be able to make this RepRap. Standard RepRap plans are usually hard to make without a RepRap. I am sure I could do a redesign with only garage tools in mind.) Also, right know there are only 9 unique parts. Everything has radial symmetry. Additionally, I could get rid of 6 of the bearings between the lower arms and the upper arms. A simple pin connection would be more than sufficient. (I am going to spend the extra $6 for less friction and symmetry.) That would bring the total to 16 bearings. That is exactly how many bearings (linear and radial) that a Printrbot has.
I may be biased but I would say the design is simpler than the other RepRaps. (I am psuedo-measuring this with part count, part complexity, plastic volume, assembly time, etc.) The firmware, however, will not be so simple but electrons are cheap.