replacing mainsprings - sessions

[crsides]

I have a sessions 8 day mantle clock I am replacing the mainsprings on. They are not enclosed in a barrel. I have let the springs down and, just before removing the bolts running through the end of the springs, thought it might be a good time to ask a question. What's likely to happen when I do this.

The repair book I am using as a guide shows replacements for mainsprings in barrels. What do I need to know before proceeding.

Thanks, Charlie

[crsides]

I have a sessions 8 day mantle clock I am replacing the mainsprings on. They are not enclosed in a barrel. I have let the springs down and, just before removing the bolts running through the end of the springs, thought it might be a good time to ask a question. What's likely to happen when I do this.

The repair book I am using as a guide shows replacements for mainsprings in barrels. What do I need to know before proceeding.

Thanks, Charlie

[Doug Campbell]

Charlie;

You need to rewind the springs fully, then find a method of securing them in their wound state. The major supply houses sell mainspring clamps, I prefer to use a heavy guage wire which I form around the spring, twisting the ends tight. Then you let the springs down until they are tight inside the clamp or wire. Separate the plates of the movement and remove the spring/arbor assemblys. In this fashion, it is much easier to disassemble. The new springs should come already clamped.

Doug

[bil2054]

I have been using heavy duty wire ties. Caution: HEAVY DUTY! Then I use a shop towel to put over it, in case it takes flight.

Bill Miller
NAWCC Member #157710
Bill's web page (http://bil2054.freeservers.com)

[tymekeypur]

Charlie ~ another point...when you're ready to remove the secured springs note how they are arranged on the pillars...which spring on which pillar...also which way they are wound on those
pillars...not a difficult thing to get them mixed up...

jc #157194

[crsides]

Thanks for the information guys. I have worked on some pocket watches, but this is my first clock. I could just imagine a giant THWANG in my future, so glad I asked.

If it doesn't feel "right", I may take it to the repair shop.

Charlie

[Tom Chaudoir]

These clamps usually come in sets, with pairs of different sizes. You may need to select the next larger clamp. Sometimes finding a way to get it around the spring can be a puzzle. Don't try to get it around the spring right away. Instead shoot for getting it around the winding arbor, away from the spring. Once it's between the plates it will be easier to place it on the spring.

Obstructions can be a problem, such as the arbor on the second wheel of your Gilbert. There's always a way. If you use the larger clamp, you won't be starting with a tightly wound spring. That means it won't be a rigid object anymore. You can move it away from the obstruction a bit.

As others have said, safety is your first concern. When the clock is finished, you will enjoy it more if you still have the correct count of fingers and eyes.

I tried heavy cable ties once. To be certain, I used 2 ties on each spring. The result was very exciting. I'll stick to clamps from now on.

Regards,

Tom Chaudoir
Milwaukee, WI
America
150429

[David B Pendley]

One other mainspring clamp that I use in tight quarters is radiator hose clamp. I used to use nylon ties but a 31 day mainspring cured me of that! Safety first.

David B Pendley, NAWCC 134028, AWI 30285, CLOCKSMITHS

[Mike Phelan]

The gap in the correct size clamp will probably never go over the wound diameter of the spring. Usually you can feed it around the part of the plate carrying the great wheel pivot and wangle it on to the spring

Keep ticking
Mike