Assembled
Wire tails soldered on, arm and Tortiose fulcrum attached ready for mounting. The original Tortoise arm is used with a bend in the end to engage the new arm. The new arm is a Meccano nut soldered to a piece of piano wire one size up from the Tortoise arms. I'm slightly concerned that the spring force on the new arm could weaken the solder joint, but so far all is OK. A more robust solution would be to solder on piece of brass tube and run the wire through this - or perhaps make a gusset plate to reinforce the joint. The idea of using the nut + bolt as a limited-angle pivot is from an article in Railway Modeller.
Taken: Wednesday 5th August 2009