RRVS Type 2 Prototype

Sun, 23 Mar 2014

In the previous Rotating Reciprocating Vertical Shaft (RRVS) Mechanism the range of movement is limited to around ninety degrees in either direction. It worked well for the Disagreeing Dog and I’m sure it will be suitable for a whole range of other models where a simple side to side movement is needed.

In the world of mechanisms there are always other ways to create the same type of movement. I’ve been experimenting with a new design that would allow a wider range of back and forth movement. (Up to three sixty degrees and beyond, in both directions) The other property of this mechanism is that the drive is much more accurate. Back and forth movement will be within a predictable, repeatable range. Here the plan:

The yellow shaft is the driven shaft. This will be attached to the character in the model. The ends of the two red strips are glued to the yellow shaft then both are wrapped a couple of times round the shaft, one of them clockwise and the other anti-clockwise.


The ends of the red strips are then glued down to the blue drive bar at opposite ends of the bar. With the shaft fixed but free to rotate, moving the drive bar back and forth rotates the shaft back and forth.


Having fitted the shaft into a box and established that the drive works, my next step will be to create some sort of linkage that can drive the blue bar back and forth.

The whole mechanism works similarly to a rack and pinion drive but is far better suited to paper as both teeth and gears are hard to make accurately.

I’m calling this the RRVS Type 2. Short for Rotating Reciprocating Vertical Shaft. Looking good so far!

Comments (6)

  • robives March 23, 2014 at 10:11 pm

    As @craig552uk points out on
    As @craig552uk points out on twitter “Prehistoric technologies are a *gold mine* for paper crafters 🙂 en.wikipedia.org/wiki/Bow_and dr… ” Thanks for that Craig!

    • hugo leandro March 24, 2014 at 7:29 pm

      Rob, this is a nice project,
      Rob, this is a nice project, indeed…I built two models, a little similar to this one. Give a look at the videos and you’ll see that instead of passing the papers ( I didn’t use paper but thread instead) transversal to the mechanisms I used to pass them in the horizontal way. I’m not sure I’m clear with my explanation but just give a look at the videos.

      http://www.youtube.com/watch?v=fnmJ_I8fC6A

      • cool022883 March 24, 2014 at 10:18 pm

        one problem Rob dosnt like to
        one problem Rob dosnt like to use things like thread or tooth picks in his designs

        I’m a paper purist! 🙂 – RI

        • hugo leandro March 24, 2014 at 10:33 pm

          Hi, Cool!
          Thanks for your

          Hi, Cool!

          Thanks for your comment…
          When I mentioned the thread I didn’t mean Rob was supposed to use it instead of paper. I just related that the paper could pass through the right place to it: in the sense of the axle and replacing the crank. That was I tried to explain but unsuccessfully, I’m sorry. Anyway, give a look at my videos in order to have the right idea.

  • Smelter March 25, 2014 at 9:57 am

    I have had a model in stock,
    I have had a model in stock, for more years that I care to disclose, which uses a thread and wooden rod that I rediscovered after seeing Robs RRVS

    Being in the camp of paper only, Robs RRVS mechanism, just might get me to make it up!

    https://www.flickr.com/photos/[email protected]/13400532453/

  • paperfan March 25, 2014 at 7:01 pm

    It looks really nice!

    It looks really nice! Automatism with paper sounds really well. 

Comments are closed.