Archive for April, 2009

Model Mechanic

April 24, 2009

Model Mechanic is a construction system simialr to Meccano. The manufacture’s description is ‘Nostalgic construction kit complete with miniature screwdriver and spanner. Different kits allow a helicopter, motorbike or racing car to be constructed from the metal shapes, bolts and nuts following the enclosed instructions. All pieces are interchangeable, so if more than one kit is purchased they can be combined to create even more impressive models.’. The hole spacing is 1 cm so Model Mechanic is not compatible with Meccano. The thread is M4. The available sets are all simple. A jeep is described in the Vehicles sub page.


Serious fun with flexagons. A companion and guide

April 18, 2009

My book ‘Serious fun with flexagons. A companion and guide.’ is duer to be published by Springer in July 2009.

A flexagon is a motion structure that has the appearance of a ring of hinged polygons. It can be flexed to display different pairs of faces, usually in cyclic order. Flexagons can be appreciated as toys or puzzles, as a recreational mathematics topic, and as the subject of serious mathematical study. Workable paper models of flexagons are easy to make and entertaining to manipulate. The mathematics of flexagons is complex, and how a flexagon works is not immediately obvious on examination of a paper model. Recent geometric analysis, included in the book, has improved theoretical understanding of flexagons, especially relationships between different types.

This profusely illustrated book is arranged in a logical order appropriate for a textbook on the geometry of flexagons. It is written so that it can be enjoyed at both the recreational mathematics level, and at the serious mathematics level. The only prerequisite is some knowledge of elementary geometry, including properties of polygons. A feature of the book is a compendium of over 700 nets for making paper models of some of the more interesting flexagons, chosen to complement the text. These are accurately drawn and reproduced at half full size. Many of the nets have not previously been published. Instructions for assembling and manipulating the flexagons are included.

Hello world!

April 2, 2009

I do not know how far it is possible to convey to any one who has not experienced it, the peculiar interest, the peculiar satisfaction that lies in a sustained research when one is not hampered by want of money.

H G Wells, Tono-Bungay.


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