I've completed the working prototype of my Shark Attack model. You can see it in animated action by clicking in the picture below.

Next step is to finish the page layout of parts and add colour. I'll be releasing this as an animated paper kit, (Shark Attack) and as an Essential Mechanism project.

Inside, I've moved things around a little since the early prototypes. The large gear is now at the bottom of the box and now has twenty three teeth. Both gears are twenty per cent smaller than the original design. The blue bar across the width of the box holds the end of the small gear's axle.

Everything fits neatly into the box and with the new layout you can now see the large gear more clearly.

Looking good so far!