Can I take this apart?

I love taking things apart, figuring out how they work, and then fixing them. Paper towel dispensers, pens, toys, zippers, Ihop chairs, anything. Today I got to dissect a tape measure.

Josh (who is playing the piano quite wonderfully as I type) and I were taking measurements out in the yard so I can plan the garden, but the tape measure wasn't cooperating. It wouldn't coil back into itself like it should. So I decided I would take it apart to figure out what was wrong. Given my track record with "fixing" things, I decided to wait until my parents got home to ask for permission to disassemble it. On more than one occasion, I have managed to completely destroy something in my efforts to fix it, so I figured I should give them a heads-up before tackling the only tape measure I could find in the house. My mom had no problem with me taking it apart, so I equipped myself with a screwdriver and set about dismantling it.

To explain what I did and why to fix it (yes, I did fix it without breaking it), I will attempt to explain in words how a tape measure works. The tape part of the tape measure is wound around a plastic spool. Inside this plastic spool is coiled a long, thin ribbon of metal that acts as a spring. One end of this ribbon is attached to the plastic spool, and the other end is fed through and wound around a slitted metal pin. When the tape is pulled out, the metal ribbon is coiled tightly around this metal pin. When the tape is released, the ribbon uncoils and the tape is pulled back in. Hopefully that makes sense. If I had thought of it, I would have taken pictures as I went to simplify explanation.

There were, I believe, two problems with the tape measure. First, the loop of metal ribbon that was supposed to hold onto the central pin was broken. This was fixed by removing the broken bit and then feeding the new end through the slot. I'm not positive about this second problem, but I'll give it a try. Just now I've come up with an alternative explanation, but I think my original hypothesis is a still a more robust explanation, so I'll stick with it. As I rewound the metal ribbon, the outer coils (which I couldn't see while I was winding it, for there was a plastic part that covered most of it and kept it from springing out and causing me harm) would periodically slip. I think the outer end of the ribbon isn't properly attached to the plastic spool. It was hard to tell, even when I took the spool apart. It is possible that the tape measure will function even if this is the case.

Once I had fixed the problem of the broken end and the central pin, I began to tightly wind the ribbon again. Then I realized that if I accidentally let go of it, my hand could be shredded by the little bit of ribbon that came through the spool to attach to the tape. I did let go of it accidentally for a split second, but fortunately I caught the plastic part and stopped its spinning. I decided to put on gloves and trade my shorts for pants to protect myself. Precautionary measures typically don't occur to me, so I'm pretty proud of myself for thinking of that.

After this adjustment, I continued to wind the spring. Eventually I reattached the tape the to bit of ribbon coming out of the spool. I let it wind itself up to be more efficient and to test how well I had fixed it. For whatever reason, the coil seems to be losing tension far more quickly than it should, so I kept on having to stop and rewind it. This tape measure may be unfixable, but we will see. Once I had fully wrapped the tape back around the spool, I reassembled the plastic outer shell. I've tested it a bit, and it is now fully capable of retracting the tape if I pull it out a foot or so, but we'll have to wait and see if it still functions properly when the tape is pulled out to its full extent.