View Full Version : Cirkut camera mainspring repair

11-05-2007, 10:10 AM
Here's an anecdote to add to the Cirkut knowledgebase, along with a request for information:

The mainspring on my No 10 Cirkut broke at the end of the Summer, and I looked around for someone to repair it. After some telephone conversations, I sent it to Bill's Clock Shop (http://billsclockshop.com/)in Fairborn, OH. In addition to clocks, they also repair antique Victrolas, so I figured they had a bit more capability than an ordinary clock shop. They had some different sizes of springs in stock, so in the best of all possible worlds, I'd have the mainspring repaired in two weeks.

This isn't the best of all worlds. They had to special order the spring. When it arrived, they rejected it (I guess this is a good thing), and ordered another. Bottom line: the repair took nearly two months. When the spring did finally arrive, I was happy with the workmanship.

I had always read the warnings against opening the mainspring case, as there were supposed to be 25 feet of razor sharp spring wire eager to leap out at astonishing speed and hell-bent on lacerating any available flesh. The folks at Bills' told me a slightly different story - that the mainspring was not one continuous spring, but was three springs wound together.

This latter fact lead to a little sticker shock at invoice time. They had quoted me a price of $60 to clean, inspect, polish and lube a spring. To repair a spring, they estimated less than $100. The bill came to $190 - $60 apiece for the two good springs, and $70 for the replacement spring.

I had also shipped them an unbroken mainspring from a No 8 Cirkut. They told me this was one continuous spring, and they cleaned, inspected, polished and lubed it for $60.

The common belief amongst Cirkut users is that the lubrication in a mainspring is provided by graphite. This was universally derided by all clock repair people I talked with, all of whom use some proprietary lubricant. My local guy uses Slik 50. One opinionated 85-yr-old stated that no informed manufacturer used graphite after the 1890's.

Now, here's my quandary and questions: the mainspring in my backup No 10 is also broken. Where shall I send it for repair? Back to Bill's, for another $190? Has anyone else gotten their mainspring repaired? Was yours also three springs wound together, or do I have a Franken-spring? If everybody else's springs are really just one spring, I'd be happy to send the broken one to Bill's, since they've now got experience.

Waddya think?


jamie young
11-05-2007, 12:28 PM
Hi Charlie
On all the springs I've opened the housing on, they were one piece. I've taken a few out. I wouldn't call them razor sharp. they just aren't very blunt. The big issue is if they let go they are hard to control and one coulld get hurt, but if one is careful it can be done. I've taken out my #16 spring to clean and got it back just fine. I've replaced a #10 spring as wel as cleaning a few others.
If I were you I would contact Ron Klein and see if he would replace it for you. No one would do a better job. Technically, He knows cirkuts better than anyone I can think of. He's also a great photographer. The cirkut is not a clock, and oil is very bad. Use graphite and ignore the clock people. A clock spring unwinds slowly, whereas the cirkut spring unwinds quickly and the oil gets sticky and is more likely to cause banding.

11-05-2007, 12:44 PM

I'm sorry I don't have time to write a shorter letter.

I hate to tell you, but the clock guys are feeding you a line of BS about springs. I have taken dozens of them apart from different #10 cameras and can assure you they are one spring. I even have five or six brand new from the factory #10 springs and they look exactly the same.

I have had great success repairing broken main springs. It has been my experience that all the springs seem to break at one end or the other so shortening the spring is the most logical solution. It is not difficult to remove a mainspring even without the proper tools. A good pair of leather gloves and common sense as to restraining the spring when you uncoil it and it will easily come out. The most important thing is to not let go of everything in the middle of unwinding it.

Anyhow, the spring ends can be heated red hot for a couple of inches and then cooled slowly. This softens the metal and then you can easily reshape it, drill a new hole etc. You do not need to re-temper the spring as it is only a few inches in length and has no great overall effect on the amount of power on the spring. The inner part of the spring needs to be curled tighter so it can start to wind on the shaft so it must remain soft anyhow. If you look at an original spring you can see the color change where the tempering was altered on the ends.

If you decide to drill a hole in a spring that still remains tempered, it can be done with this simple trick - Use a drill press and a piece of blank steel the same size as the hole but totally flat on the end. When you try drilling the hole, it makes the spot red hot but can't drill through. This is perfect as it is now annealed and you can replace the blank steel with a drill and easily make the hole you need.

With your old spring out, you can dress it smooth with very fine sand paper and files. Make sure there are no nicks or breaks in the metal as it will break again in a heartbeat if left. Then wash and wipe it really good before installing. USE GRAPHITE. That worked for 80 years without problems and you can still buy it in any good auto parts store. Using grease, even Slick 50 poses serious problems when shooting in low temperature conditions and it sucks power out of the spring. I can't remember how many cameras I have fixed by simply washing grease or oil out of the spring and putting graphite back in. Unless you are going to Baghdad to photograph troops in August, use graphite.

Clock guys are OK people, but they think clocks and not motors. Motors are used in Cirkut cameras. Clocks must run with very little friction to maintain accuracy. Even the gears in clocks are different from Cirkut cameras as they are designed to have low friction but are not always in contact with their mate. The Cirkut gears are designed to run smoothly without interruption. They do not mix. Also a clock guy will repair a worn bushing by reducing the thickness of the metal with a special punch. Less surface area is again good for clocks but bad for fast running motors.

You would think the people you dealt with that repair victrolas would have an understanding of all of this but I guess not. Also, new spring material is readily available, the last time I looked is was around $75 for 500 feet. That's a lot of Cirkut cameras.

And yes, you have a Frankenspring, but that's not a bad idea to use three springs coiled together if you can figure out the amount of power it puts out. They would have to be three times thinner and that might be a problem. I suspect the spring would run nicer and longer, but not have much power. A good spring with a 64- 66 tooth gear will run the Cirkut camera for 2 and 1/2 full circles. Originally you could order a stronger spring but it was shorter too because it was thicker. I've seem them and wasn't impressed because they were also harder to wind.

You should be clever enough and brave enough to work on your own springs without getting one stuck in your forehead. I've been doing it for 27 years and still have all my fingers etc. The only time a Cirkut ever drew blood was my fault removing a broken ground glass. I might even hold a record by having removed springs from six #16 Cirkuts without killing myself and they are 40 feet long.

Hope this helps,

Ron in Alaska

11-05-2007, 10:13 PM
Thanks, Jamie and Ron, for your replies. It good to hear the voices of experience, particularly without the 'don't try this at home, kids' warnings.

How thick is the spring material? The spring from the backup camera seems to be 0.020". McMaster shows item 9036K217 - 1095 spring steel, 0.020" thick, 1" by 100' for $97.05. Does this sound like the right stuff? My Frankenspring, as I recall, was 0.010".

I guess I'll try pulling the spring out of the backup camera's case and anneal the end (both springs broke at the arbor). My real fear isn't getting hurt extracting it, but that it'll be difficult to get back in the case. It's always easier to make something into parts than make something out of parts.

If that works out, I'll see about replacing the Frankenspring.

Thanks, again.

11-06-2007, 07:30 AM
.020 seems too thick. That might be the heavy duty spring that I don't like.

It's been a while since I've measured one, but I believe .013 was the correct original thickness. I suspect .012 or .014 would work.

I guess I'm just lazy because I can get to my spare springs easily. I'll try to measure one today for you.


11-06-2007, 09:11 AM
It's been a while since I've measured one, but I believe .013 was the correct original thickness. I suspect .012 or .014 would work.


Thanks, Ron.

I could only measure the edge of the broken section, still attached to the arbor and wound tight in the case. It's a little rough looking, and, of course, not a flat surface, so my measurement is prone to being over.


11-06-2007, 10:18 AM
Long ago in my youth I once repaired a main spring on an Edison Phonograph. Not even having the knowledge already given here, I feared ruining the "temper" so I made my new holes with a chain saw grinder. Just started at an angle and worried a hole right through. It worked perfectly and I was quite proud of myself.

11-08-2007, 08:25 AM
Just a quick update: extracting the spring was quite easy. Using leather gloves (and eye protection, of course) and starting at the broken arbor end, I pulled it out half-a-turn at a time, holding the unwound part into the case with a finger.

The spring is 20 feet long, 0.015 inches thick.

For the curious, I've attached pictures of the spring and case, the case with arbor and side attachment points, and the tempered end of the spring.

I won't be able to do anymore on this project until next week (or maybe next month), but I'll let everyone know how it progresses.