The VV-XIV I’m working on has 4 mainsprings, one (at least) of which I knew was broken. So, fingers crossed that the break would be an outside/middle break, I dug into it today. I’ll explain what an “outside/middle break” is in a minute.
Got the main shaft out, and started checking the springs right to left, as they were oriented on my bench. Number three had the break, and thankfully it was an outside break. Here’s a look:
The mainsprings are coiled in the spring barrels, two in each of the two barrels (one sits on top of the other with a spacer between them). This was the top spring in the second barrel I checked.
Each spring is engaged in two places: at the end on the outside (in this case, a pear-shaped hole slips over a short “pin” in the spring barrel) and on the inside (in this case, the spring is shaped into a configuration so that part of it fits in to a groove in the center arbor).
I’ve done inside and middle/outside repairs many times, and I HATE having to repair inside breaks. In fact, for as many times as I’ve fixed them, I’ve just thrown in the towel and ordered a new spring just as many times.
When the spring is broken somewhere in the middle (which is not common, at least in my experience) it is fixable, but I will usually just get a new one to put in. My thinking is that if it weakened in the middle enough to break, there’s a possibility that something is wrong with it, and it’s just easier to replace it.
Outside break fixes are quite easy. Cut the broken end off, re-shape, punch two holes and file to a pear shape, bend the end inwards a bit (to get it to catch the pin easier), torch it, cool it, install.
The REAL issue with any of this work is how INCREDIBLY MESSY it is. I forgot just how disgustingly gross this is, with hardened/semi-hardened 100-year-old grease. See that black mass below the end of the spring in the photograph. That just a small amount of the grease I had to remove just to be able to get it all apart and see what I was doing. I’ve had to use a chisel in the past, for grease that had “petrified”. This time a large screwdriver did the trick.
In the past I kept a dedicated tank in my shop for this work. Now, I’m doing this in my woodshop, in a Home Depot bucket in my utility sink, trying like hell not to let any of the grease, oil, and mineral spirits get on anything. It’s a dance. I’ll be glad to get this out back together and back in the machine.
Since I had three of the four mainsprings out already, I figured it I sense to just remove them all, clean them (and the rest of the motor) re-install and adjust, so it’ll hopefully have another 100 years of functionality.
I don’t like greasy messes like this. I think a tank in my garage might be warranted. Because ew.
Have a great day!