A Meccanograph made from only parts in the range 1 to 50.
Adapted from an Andreas Konkoly model from the November 1972 issue of Meccano Magazine. The main problems encountered in staying within the challenge criteria were that no long bolts, brassware (apart from slide piece) or pivot bolts could be used. This made construction of cams and the crank arm for the pen beam difficult. Without collars available, and spring clips giving poor resistance to axial thrust, all gearing was arranged such that pinions were used instead of collars.
In the Konkoly original the pen beam was driven by a helical gear pair. These were substituted by a 3:1 bevel pair.
This model utilises the 6" pulley which is rarely seen in models. It has been covered by a thin plastic film drawn tight like a drum-skin, though this method was not as successful as hoped - the paper tending to creep slightly during use.