broken mainspring

[luiazazrambo]

Hi *,

I have another issue with my travel watch, the end of the mainspring is broken. Can this be fixed or do I need to resource a new mainspring? Where can I read about mainsprings as how to identify their size to be able to buy a new one?

I am sorry I am completely new and I do not seem to able to find the info what I am looking for.

Best regards,

Lui

[yankeedog]

Busted is busted. Can't be repaired and can't be trusted. Time to spring for a new spring.

[yankeedog]

you can usually look them up according to the manufacturer and type of movement.

[luiazazrambo]

7 minutes ago, yankeedog said:

you can usually look them up according to the manufacturer and type of movement.

Can't, its a vintage travel watch. It says 8 days swiss made and there is some more writing on the dial I cant read, not even with magnifier, because the dial is discolored and old. Wanted to post another topic with the picture of it but it seems my sd card just died too. Movement only says swiss made. First watch causing me headache. Spent about ~2 hours just to put the pallet back. I was close to a nervous breakdown. Went to bed after 5 am daughter woke us up at 8. This is a difficult business to do.

[luiazazrambo]

25 minutes ago, yankeedog said:

Busted is busted. Can't be repaired and can't be trusted. Time to spring for a new spring.

Thought it would be easier to fix as it seems that the extra metal plate was added to the main spring originally. The main spring itself is ok, but the metal plate snapped in two.

[luiazazrambo]

I did not reach so far with watching Mark's videos: 

 

[Tmuir]

You could in theory fix it, but I would measure the mainspring and see if you can buy a replacement.

They used to rivet the extra bit on, but now its usually spot welded, but in some older watches they just have a loose end mainspring hook, which you might be able to do for this spring if you can't find a replacement, but it would be tricky.

W.J. Gazeley's book Watch and clock making and repairing explains how to do this. (1950s book). I will take a photo and post it from the book shortly.

[Tmuir]

Pages from the book that explain how to make a loose hook end for a mainspring

[yankeedog]

well it was made by somebody... post pics front and back. 

[watchweasol]

Hi is this a travel clock as the spring looks a bit coarse for a watch If so as Tmuir says they an be repaired, I personaly have used both the rivit and the loose end fittings and done right are quite sucessful but it means softening the spring end  either to bend it in the case of the loose end fitting  and also the rivit method  for drilling  but care must be taken not to crack or craze the spring

[luiazazrambo]

Very interesting Timur, thank you for this. Why does it say that if you bend the mainspring back to form the loose piece solid that it is soft? Is it because it gets soft from the heating?

[luiazazrambo]

2 hours ago, watchweasol said:

Hi is this a travel clock as the spring looks a bit coarse for a watch If so as Tmuir says they an be repaired, I personaly have used both the rivit and the loose end fittings and done right are quite sucessful but it means softening the spring end  either to bend it in the case of the loose end fitting  and also the rivit method  for drilling  but care must be taken not to crack or craze the spring

Umm... I just started to deal with timepieces. I guess its a travel clock. I personally had the impression they used a pocket watch.

[luiazazrambo]

4 hours ago, yankeedog said:

well it was made by somebody... post pics front and back. 

Its dark here and this is what I could do with my phone. Cannot use my camera atm as the SD card died in it.

[Tmuir]

On 2/16/2019 at 6:42 AM, luiazazrambo said:

Very interesting Timur, thank you for this. Why does it say that if you bend the mainspring back to form the loose piece solid that it is soft? Is it because it gets soft from the heating?

You must remove the section of the spring the will become the loose bit before you heat the mainspring as heating the mainspring to red will anneal the spring steal so it can bend, not break. If you do not remove the bit of the spring that will become the loose bit first it would also be heated and annealed and then under tension in the barrel when the watch is would up it could buckle and let the mainspring go which would most likely damage the watch

[vinn3]

On ‎2‎/‎15‎/‎2019 at 6:17 AM, yankeedog said:

Busted is busted. Can't be repaired and can't be trusted. Time to spring for a new spring.

  not true.  I have received both watches and clocks with a "shortened  a main spring",   I have shortened them.  vin

[vinn3]

On ‎2‎/‎15‎/‎2019 at 12:22 PM, watchweasol said:

Hi is this a travel clock as the spring looks a bit coarse for a watch If so as Tmuir says they an be repaired, I personaly have used both the rivit and the loose end fittings and done right are quite sucessful but it means softening the spring end  either to bend it in the case of the loose end fitting  and also the rivit method  for drilling  but care must be taken not to crack or craze the spring

   with your staking set.  you can "broach"   a hole,  in spring or annealed spring. vin

[MrRoundel]

I had seen that mainsprings can be repaired when the end snaps off like that.  I have never done it. However, that mainspring looks pretty well "set", and may not be applying optimal power to the train. However, if there is still good resistance power to the MS, and you did repair the end, it may just become a 7 7/8 day watch. A new spring would be best, but the lesson learned in repairing such a spring would not go to waste. 

With a mainspring gauge or digital calipers you should be able to get the dimensions of the size you need, i.e, thickness and width. You can stretch the spring out along the edge of a table or desk with a tape measures, or(?) to get the length. When you do this, wear eye protection, and be sure nothing is around that can be damaged if the spring takes flight on you. Good luck.

[vinn3]

    there is an aftermarket, pocket watch main spring that can not be repaired.   a "lifetime  main spring" very heavy duty!  i have one,  few have seen one.    vin 

[luiazazrambo]

On 2/17/2019 at 7:11 PM, MrRoundel said:

I had seen that mainsprings can be repaired when the end snaps off like that.  I have never done it. However, that mainspring looks pretty well "set", and may not be applying optimal power to the train. However, if there is still good resistance power to the MS, and you did repair the end, it may just become a 7 7/8 day watch. A new spring would be best, but the lesson learned in repairing such a spring would not go to waste. 

With a mainspring gauge or digital calipers you should be able to get the dimensions of the size you need, i.e, thickness and width. You can stretch the spring out along the edge of a table or desk with a tape measures, or(?) to get the length. When you do this, wear eye protection, and be sure nothing is around that can be damaged if the spring takes flight on you. Good luck.

For me it is important to learn how to repair the main spring or even measure the mean spring as i am a beginner, it would be nice to fix the clock/watch on top of that as a reward of my efforts. (as far as I can see i am going to be in trouble with the hairspring too)

[luiazazrambo]

I see i still need to file some edges and probably not the best mainspring repair ever, but as my first ever try I am more or less satisfied. Hopefully it is going to work in the clock.

[luiazazrambo]

Another mistake.. bent the spring the wrong side... i had to cut it off and bend it again however it seems that I fixed the mainspring and the clock started to work. Yes it is shorter now by 10-15 mm but it works. I am really happy.

[AndyHull]

Nice work.

10 to 15 mm over the length of that spring probably isn't going to have a huge impact. It will be interesting to find out how long it runs on a full wind. I expect it to be less than when it was manufactured, but in part that is going to be down to the aging of the spring as much as to the fact that it is now slightly shorter.