2009 Exhibition Sign
Built by Tim Surtell in October 2009
This sign came about because I needed an exhibition logo for the SELMEC website and exhibition video.
The ‘09’ of ‘SELMEC Meccano Exhibition 09’ was an obvious candidate for being built using Meccano gears, so I attempted this first. This became the Meccano component of the animated logo used on our website and elsewhere (bottom right).
The rest of the text was easily constructed using Meccano strips, though the letter ‘B’ caused a few problems initially.
The word ‘SELMEC’ happens to be the exact width of a braced girder, which is the club’s symbol, so my original plan was to fix a braced girder below the word. This idea was abandoned due to a lack of space on the eventual framework.
The words get progressively longer, so this gave me the idea to use a triangular framework to support them. To keep the cost of new parts and paint down I based the framework on triangles made using 5½ strips as I have a great many of these in stainless steel.
In thinking about how to drive the ‘09’, I realised that if a worm drive were used, a long rod could run from left to right under the word ‘Exhibition’. Placing three cams on this rod would give the sign extra activity by raising and lowering the ‘I’s.
The long rod is driven by a further worm gear engaging with a pinion, the input rod emerging from the rear of the sign where a pulley is fixed to it. A band drives this pulley from the spindle of a small electric motor.
Unfortunately the worm gears have the effect of slowing the sign down somewhat especially the ‘09’ gears. A fellow member of the club suggested replacing the ‘0’ worm gear with a driving band directly between the long rod and the boss of the ‘0’ gear, but I couldn’t get this to work without slippage.
To complete the sign I built a spotlight on an arm. A standard 12V 20W dichroic lamp sits snugly inside a boiler and is secured by its connecting pins to a terminal block mounted on a piece of stripboard.
All parts are either stainless steel or are refurbished parts repainted using red, yellow and black spray paint.