A comment on the article's video had two interesting points: > There is linear stress problems that can occur, a single "activation" line (clock signal through

A comment on the article's video had two interesting points: > There is linear stress problems that can occur, a single "activation" line (clock signal through a train of locks) can eventually reach a point that the mechanism will be unable to move at all. You can see an example of that long single activation line in this gif http://www.merkle.com/images/4_phase_shift_register_v4.gif http://www.merkle.com/images/4_phase_shift_register_v4.gif and described in more detail in this part of the video: https://youtu.be/yVX9Ob4SjGA?t=769 https://youtu.be/yVX9Ob4SjGA?t=769. I was surprised this wasn't explicitly addressed in the talk. Transistors aren't just powerful because they can be off or on (switch) but also because they can amplify signals (a lever). Edit: The paper does address this in section 4.5, saying that "The method for dealing with scaling is to isolate individual cells in a shift register (or more generally, individual clocked logic elements, such as Fredkin gates) by using the four-phase clock. That is, forces along signal lines cannot move beyond two cells before encountering a locked lock, preventing any accumulation of forces over long distances. At any point in time, a cell is either blocked from transmitting forces to adjacent cells, or can transmit forces only to one other cell (either the predecessor or the successor)" and "Force accumulation in link logic systems can be mitigated because each lock acts as a mechanical amplifier, with a small force controlling a much larger one." > I'm really loving the idea of mechanical logic gates and computers... it's far easier to produce in 3D print, which will be vital in space exploration and colonization. Question is, what additional primitives are needed to construct all the primitives (locks and balances) from a bin of links and rotors? Maybe a "lifter" that raises a hinge pin out of 2D plane so it can be placed in a rotor.