Loop-End Clock Mainspring Description
Loop-End clock mainspring description would be a long flat spring with a loop on one end. The loop gets wrapped around a movement's outer plate pillar. In other words this is the type of mainspring you can see when you look at the movement. It is not contained in a barrel style container. If the spring is in a barrel and you cant see the actual spring, please see the hole end mainspring page instead.
If the mainspring is broken it will seem like its winding up when you turn the key, only to snap back again. So you end up just winding it forever with nothing happening. When the mainspring is broken they sometimes stick way outside the side of the movement. In extreme, the mainspring will break and cause the clock case get damaged. This is not as common and usually the clock case is fine.
How they come
These mainsprings come wound up with a tie wire around it. Usually they can be installed in the movement just as it comes, wound up. Once the movement is reassembled perfect, you can wind up the mainspring and cut that wire off of it. As mentioned in other sections, treat these things with respect and caution. Wear safety glasses when working with mainsprings and also gloves. Seriously, these things can punch you, wack you, cut you, and snap at you. Just use caution because they do pack a punch.
clockworks.com offers a repair service if you just want us to take care of it for you instead. It would be a movement restoration job and not just a mainspring swap. If you choose to go this route please email a picture of the movement. We will see the picture and quote for the work. Please email to [email protected]