Home Forums General Discussion Forum How can I make a tiny compression spring?

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  • #49173
    cazclocker
    Participant

      Some of you may have seen my thread concerning my English-made Watson-Keeless gravity clock. I finished the restoration and it’s in the testing phase now. But in the process, I managed to lose a very tiny spring that was placed on one end of a wheel’s arbor – see the picture below:

      The spring’s function is to keep a small pinion with sawtooth-shaped teeth engaged with cut-to-match teeth on the bottom of the wheel you can see in the picture. When the gravity clock needs to be rewound, the case is lifted upward and the teeth disengage just enough to allow vertical movement. Then, the teeth re-engage allowing gravity to once again drive the movement. It was frustrating to lose a tiny part like that indeed – my question is how can I best make a replacement? I did the best I could with a piece of #32 galvanized steel wire wrapped around a machinist’s pin gauge (sized a few thousandths larger than the arbor) and then clipping to size. The problem is that it’s not spring steel, so while it “sort of” compresses, it doesn’t do the job as well as a purpose-made spring would do. The spring was/is made from extremely fine spring wire – it reminded me of the wire used for coil windings in small transformers or electric guitar pickups.

      Suggestions, anyone? If I can fabricate a good replacement I’ll disassemble & reassemble one last time.

      …Doug

      #59012
      tmac1956
      Participant

        Doug:

        You could probably apply these techniques, only on a smaller scale.

        https://www.youtube.com/watch?v=i1x5_S0Pq4k

        I hope this helps!
        Tom

        #59013
        arutha
        Participant

          You could try the spring from a retractable ball point pen and if that dont work try here? https://www.cousinsuk.com/catalog/clock-parts/clock-coil-spiral-springs-hair-springs/spiral-coil-springs
          Paul.

          #59014
          cazclocker
          Participant

            Thanks guys.

            Paul, the spring from a ballpoint pen is the first thing I thought of – but the inside diameter is much too big to work with this application. The spring assortment you pointed me to sounds handy, but there’s no indication of the included sizes.

            Tom, that video is exactly what I’m looking for – if I had the appropriate wire, I could just wind my own spring on my lathe. In the video, the narrator mentions a website about springs that he couldn’t recall offhand, but that he’d include in the comments section below the video. I couldn’t find any such reference. But, one thing he mentioned that might be useful is the idea of making a compression spring by stretching a expansion spring. If I recall, I think I **MAY** have an expansion spring sitting in one of my parts bins – the one I’m thinking of is one of several I salvaged from an old printer laser ink cartridge – if I recall correctly, it’s so tiny it might just work!

            …Doug

            #59015
            david pierce
            Participant

              Doug,
              General hardware stores and industrial supply houses such as MSC sell springs. You may also find springs for sale at a home improvement store in the hardware section.
              david

              #59016
              cazclocker
              Participant

                @david pierce wrote:

                Doug,
                General hardware stores and industrial supply houses such as MSC sell springs. You may also find springs for sale at a home improvement store in the hardware section.
                david

                David, thank you! Yes, you’re right – I checked at my local hardware store. The problem is that I need the spring to have an internal diameter of only 0.055″ or so – just enough to clear the arbor of the wheel shown in the picture above. Also, the wire used in commercial springs are MUCH too thick to be useable for this little clock. I’ve set my sights on .006″ music wire, and wrapping my own compression spring. If ONLY I hadn’t lost the original spring! Sigh…I guess that what part-catcher drawers are for at my bench.
                …Doug

                #59017
                david pierce
                Participant

                  Doug,
                  I bought a watchmaker bench a while ago and it has a part catcher tray. I had to conclude that in my case the tray is useless. Today I took a wrist watch apart and pulled out the mainspring barrel. When I tapped the arbor with a hammer to remove the cap the spring flew out of the barrel and twisted into a rats nest. Then I heard PING THUNK which was the arbor ricoching off of two walls. I found the arbor on another bench next to my watch bench. My next trick was removing a staff out of a balance wheel. I heard the staff launch into orbit but it landed on my watch bench so I didn’t lose either part. I think I need to cover this stuff with a sheet of clear plastic next time to prevent the parts from sailing across the room. i should know better but it seems like I never learn. 💡
                  david

                  #59018
                  cazclocker
                  Participant

                    @david pierce wrote:

                    Doug,
                    I bought a watchmaker bench a while ago and it has a part catcher tray. I had to conclude that in my case the tray is useless. Today I took a wrist watch apart and pulled out the mainspring barrel. When I tapped the arbor with a hammer to remove the cap the spring flew out of the barrel and twisted into a rats nest. Then I heard PING THUNK which was the arbor ricoching off of two walls. I found the arbor on another bench next to my watch bench. My next trick was removing a staff out of a balance wheel. I heard the staff launch into orbit but it landed on my watch bench so I didn’t lose either part. I think I need to cover this stuff with a sheet of clear plastic next time to prevent the parts from sailing across the room. i should know better but it seems like I never learn. 💡
                    david

                    Hmmm……….David, you might be on to something. Reading your post made an idea occur to me – it wouldn’t be all that difficult to construct something similar to a sandblasting cabinet. If you built a simple cube out of, say, wood sticks or something, you could stretch clear plastic over it. In the front you could cut circles and insert thin rubber gloves. Then you could see your clock or watch, stick your hands in the gloves, and take apart your project to your heart’s content without fear of anything flying off into the distance. Just a thought!
                    …Doug

                    #59019
                    willofiam
                    Moderator

                      Doug, maybe you have already thought of this, guitar strings, cannot remember the sizes they come in but would be a good candidate for material. William

                      #59020
                      cazclocker
                      Participant

                        @willofiam wrote:

                        Doug, maybe you have already thought of this, guitar strings, cannot remember the sizes they come in but would be a good candidate for material. William

                        William, great minds think alike…LOL :D Actually, I thought of that yesterday. The smallest gauge guitar string that I know of is .009″, which may work out just fine. I’m going by a music store later today – I’ll pick one up and give it a whirl.
                        By the way, I love your website! You not only have all the equipment to make us drool, but I love where your heart is, brother!
                        …Doug

                        #59021
                        tmac1956
                        Participant

                          Doug:

                          You can find them at 0.007.

                          Just FYI…
                          Tom

                          #59022
                          cazclocker
                          Participant

                            @tmac1956 wrote:

                            Doug:

                            You can find them at 0.007.

                            Just FYI…
                            Tom

                            .007″? Really? Boy, that’s some thin string! Thanks for the heads-up! I’ll be headed to the music store later today.
                            …Doug

                            #59023
                            willofiam
                            Moderator

                              Thanks Doug for the kind words about the site, my son has created that for me and it is still a work in progress (like me 🙄 ), wanting to add more to it when I can, as far as the shop it has recently changed, soon I hope, I will post it. In all things I have needed the guidance and blessings which I believe has gotten me this far. William

                              #59024
                              namonllor1953
                              Participant

                                Sorry for the late reply.
                                Model Engine Builder had an article on making a spring winding mechanism a while back.

                                Here’s a link to the magazine:
                                https://www.modelenginebuilder.com/

                                Here’s a phot of the winder. The small spring on the bottom is about the radius of a nickle.

                                #59025
                                cazclocker
                                Participant

                                  Thanks for the link, namonllor. That looks like a wonderful project to have around the shop!

                                  But more to the point, I finally made a viable little spring to replace the one I lost (I can’t believe it, but it’s still in the shop somewhere!). I made it last week, and it works absolutely perfectly. How I made it couldn’t be simpler – I went to a local music store and bought a couple of single guitar strings – music stores will typically have a box laying around somewhere with leftover single strings. I bought a .007″ and a .008″ (couldn’t find a .006″) for a dollar each. Then I took my set of machinist’s plug gauges and experimented with different sizes to wrap the string around – the thing is that after wrapping by hand, it will relax a little bit so it will have an inside diameter a bit larger than the gauge you wrapped it around. Turned out that a .056″ plug gauge worked perfectly – I just held the end of the string tightly with my thumb & fingers, and wrapped with my other hand – once I got the coil about 1/4″ long I took a pair of duckbill pliers to pull gently on the end to try to “set” the coil dimensions. Even so, it did relax a bit but it still fit perfectly over the .0625″ wheel arbor that the spring needed to fit over.

                                  So I made a nice one-off spring, but boy my thumb hurt…
                                  …Doug

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