Making a spring for an American R&E Co Rim Lock

Well another day and another interesting job. Making a spring for an American Rim Lock made from cast iron by Russell & Erwin Company with patent from the 1860s. How did an American lock make its way to Australia? More questions for my client I suppose.

Post and Bar method of twisting wire into a spring.

Opening the case of the lock I found a broken spring that needed to be remade. I used a post around the same diameter as the pivot point and a bar with a hole the same gauge as the wire to make a new spring. I clamped the wire and post in the vice, threaded the wire through the bar and twisted the wire around the post.

Couple of sample springs

Just need to work out the turns and the 'arm' positions. Turned out that the spring operated the latch but also put pressure on a deadlocking bar that hold the bolt in the locked or open position.

New spring in place 

Bolt in place fitting over the new spring.

Interesting feature of a privacy snib which locks the latch in place to lock out the handle to prevent someone outside from opening the lock with a key. More soon when the keys come in from Tasmania.