Can I sub T end for unavailable DB? (Vostok 2809)

[mikepilk]

Sorry I didn't realise you were trying to measure the depth of the barrel. You could measure the total depth of the barrel, then subtract the depth of the base by measuring where the teeth are.

[tomh207]

Pretty much anything on this page would be the proper tool to measure the depth of a barrel 

 

https://www.rdgtools.co.uk/acatalog/Depth-Micrometers---Gauges.html

 

Tom

[NigelTufnel]

@AndyGSi That's what got me good this time.  The depth rod just kind of is floating around, not held in place or in alignment.  I seem to remember int he past having one with a metal strap across the back at the end to keep this from happening.  When you have a 6" long caliper that thing really can move.

Also, a 6mm anvil is actually too large here.  I need it to be smaller becauseof the ridge at the hole.  << sigh>> I've ordered a new micrometer anyway, perhaps I will buy a tip for it too.

BTW, I have the 0.2mm mainsprings on order, and going to pray maybe they are a little undersized!

[NigelTufnel]

Thanks @tomh207 ! I ended up using a micrometer with the help of an M3 lock nut.    I placed the lock nut inside, but around the center ring and did a lot of math.

Here's what I've measured:

Barrel inner wall:  2.24mm.

Lid thickness:  0.3mm but 0.1 mm protrudes above the top of the barrel, so only 0.2 mm count.  By my math:

2.24 - 0.2 = 2.04 mm

Is that tall enough for a 2mm spring? A reminder that the original mainspring measures 1.89mm. 

Edited September 14, 2024 by NigelTufnel

[NigelTufnel]

Kind of on a related note, while inspecting the third wheel for dirt and movement I discovered the outer wall of the barrel has a little grease line halfway up.  I'm going to have to get to the bottom of that!! I did clean the barrel before, but I may have focused much more on the inside than the external wall.

[NigelTufnel]

As promised, I ran the free oscillation test.  It did go back and fort 100 times (just barely) but the last few were of very low amplitude.   Also, the whole movement feels insanely easy to move.  I mean, the lightest touch on the winding wheel and every thing spins.

[NigelTufnel]

Well my friends, the donor barrel has a new 1.98mm wide mainspring.  The one thing I'm having trouble with right now is the arbor feels loose.  Suggestions on tightening the mainspring end before I close up the barrel?

[mikepilk]

3 minutes ago, NigelTufnel said:

Well my friends, the donor barrel has a new 1.98mm wide mainspring.  The one thing I'm having trouble with right now is the arbor feels loose.  Suggestions on tightening the mainspring end before I close up the barrel?

The crucial thing is that you have a smaller cylinder inside the inner coil before pressing it smaller. Or it will kink and break. Hands up all who have done that - yep, everyone. 

 

[AndyGSi]

46 minutes ago, NigelTufnel said:

Well my friends, the donor barrel has a new 1.98mm wide mainspring.  The one thing I'm having trouble with right now is the arbor feels loose.  Suggestions on tightening the mainspring end before I close up the barrel?

Can you post a photo.

[NigelTufnel]

3 hours ago, AndyGSi said:

Can you post a photo.

Here you go.  The original/donor mainspring in the background.  I can put the arbor in the new one, and it LOOKS right but there's almost no tension in the coil to hold the arbor in.

[AndyGSi]

Can you show it with the arbor in.

[NigelTufnel]

8 minutes ago, AndyGSi said:

Can you show it with the arbor in.

 

[AndyGSi]

Doesn't look a great deal different to this from the watchguy.

As long as the arbor is OK then I'd give it a go.

[NigelTufnel]

Thanks, @AndyGSi - The arbor looks decent enough.  I have two of these new mainsprings... both of which are probably too wide, but I happen to have all the right tools.   Just have to clear off enough space to avoid fire starting. 

After all the work of polishing the main barrel holes and the arbor, and heat treating the mainspring I'm probably going to be left wiht an inoperable watch.  I took this thing apart so long I don't even know if I can locate the case screws.  (puts water gun to head)

[NigelTufnel]

Minor update:  Waiting on tools.  After removing the new mainspring I see how bent it is, and that I will need to use a real mainspring winder to attempt this again.  My expensive temp controlled soldering iron was broken.  Temp reading was off (thank goodness I have a no-contact thermometer) by a lot.  Turns out ceramic heating element was broken in two.  Also waiting on bench block.  By the time this refurbishing is done I feel like I should be able to manufacture my own parts...

[AndyGSi]

3 hours ago, NigelTufnel said:

After removing the new mainspring I see how bent it is

Where did you get it from as I presume it must have been bent before you installed it?

[HectorLooi]

So, from what I understand, you haven't fitted  T end mainspring before. Is that right?

It can be a little tricky. It has been discussed before on this forum. 

Do let us know if you run into any problems when your mainspring winders arrive.

[NigelTufnel]

Hi @AndyGSi - The mainspring came from Cousins UK.  The ring was 0.5mm too big for the barrel I'm afraid so I couldn't just drop it in.  I hand wound it in, and that's when I discovered the arbor was too small.  When I took the new spring out and rested it on the bench I could see it's not resting flat, most likely due to being manually wound in.

@HectorLooi - Actually this is my 3rd attempt. I cleaned and lubricated the original barrel/mainspring and yes, I wrestled with the T part.  I bought 2 new ones, so I'm going to use the first one as a practice unit to fix the inside curl (I forgot the name for that part of the mainspring) and then attempt the same with the Never Removed From Box other one I have.  As I mention above, the mainspring ring is too big so no matter what I'd end up having to either manually insert or rewind it.  Since I'm attempting a spring that is 0.1mm wider and have almost no clearance left in the barrel I'm going to want to do the best possible job of inserting a new mainspring. 

Thank you for offering to help.  I have never ordered before so I am not even sure I got the right parts.  I'm sure I'll need assistance despite how easy the videos look.  This was going to be such an easy project.  Buy a new spring, pop it in, boom.... Hahahahah.

Edited September 22, 2024 by NigelTufnel

[HectorLooi]

I'm not sure if a new spring can even be pushed in from a correct size ring. The T end has a tendency to jump out of the slot at the bottom of the barrel. I used to hand wind T springs but that usually ends up scratching up the floor of the barrel.

I learnt how to use a mainspring winder to fit T end springs from @JohnR725. His method is to leave a short "tail" sticking out of the winder, fitting the T into the slot and holding it in the slot by pressing down on it with the back end of a brass tweezer while pushing the spring out of the winder. Takes a bit of practice but it works like a charm.

[JohnR725]

2 hours ago, NigelTufnel said:

I hand wound it in, and that's when I discovered the arbor was too small.  When I took the new spring out and rested it on the bench I could see it's not resting flat, most likely due to being manually wound in

The problem with generic mainsprings are they were not designed for the watcher putting them into. So things like the center part of the spring that curvature is not actually specified as a size. So depending upon the generic spring they are brutally to be too small or too big. Or on some occasions the whole inside might not even be the right size. I sometimes run and that with American pocket watch springs where it just isn't quite right.

Then it is generally frowned upon sometimes to hand wind mainsprings in because you put a lot of pressure at weird angles and as you've discovered your mainspring is no longer flat. The problem with not being flash is when you wind it up in the barrel wall sealed up in between fully wound up and fully unwound you get a very interesting condition where the spring now is kinda free-floating and the curvature will now put pressure on the lid the bottom and you'll lose power that way. You can actually win you disassemble a barrel you can see where the pressure pushing outward where's the barrel lid and/or bottom which is why we try not to hand wind springs in. A lot of how bad is going to look is dependent also upon the actual temper of the mainspring some of them are better than others

1 hour ago, HectorLooi said:

I'm not sure if a new spring can even be pushed in from a correct size ring. The T end has a tendency to jump out of the slot at the bottom of the barrel. I used to hand wind T springs but that usually ends up scratching up the floor of the barrel.

Not sure if I learned this in school or where I learned it but yes attempting to push mainsprings out of rings that have ends such as T or T brace or anything weren't protrudes out the sides attempting to just push it out of the ring and have it magically stay in place is extremely unlikely.

1 hour ago, HectorLooi said:

His method is to leave a short "tail" sticking out of the winder, fitting the T into the slot and holding it in the slot by pressing down on it with the back end of a brass tweezer while pushing the spring out of the winder. Takes a bit of practice but it works like a charm.

Then if anyone needs pictures I have pictures. This by far as the best way you do want to make sure that the protruding part will actually go through the hole in the barrel. Often times aftermarket springs the T part can be bigger than the hole for instance.

[NigelTufnel]

4 hours ago, HectorLooi said:

His method is to leave a short "tail" sticking out of the winder, fitting the T into the slot and holding it in the slot by pressing down on it with the back end of a brass tweezer while pushing the spring out of the winder. Takes a bit of practice but it works like a charm.

Thanks guys, definitely going to practice this.  Thanks for the details, @JohnR725 - It's all kind of how I imagined it.  I'm a week away from being able to attempt this again, so future status reports may be delayed as time permits and tools arrive.

[nevenbekriev]

Hi Nigel,

Several things to say here...

First one:

in situations like this

On 9/19/2024 at 11:40 PM, NigelTufnel said:

 

(where You were worried that the internal coil is loose and no pressure to the arbor), You need just to try to wind and see if the hook of the arbor will catch the spring end. It is obvious from the picture (to me) that it will catch.  If so, then You need just to close the barrel and be happy.

Then, I will open a secret for You: It is not possible to heat treat the spring with electric soldering iron. No mater what You see in the videos, this is not possible. I assure You that if one can do something with the help of the soldering iron, then He will be able to do the same thing with the soldering iron not plugged in the wall socket. The difference will be only that there will be no danger to burn His fingers on the hot iron...

Winding the spring in the barrel with hands can be done without damage to the spring, but one must feel the spring and not to bend it more than needed. Practice helps much.  One thing is for sure: using mainspring winder is not less dangerous for the spring if one has no practice too.  The winder must be correct for both the spring and the barrel and one must know the habits of the winder in order to prevent the spring from damage.

And one more secret: if the spring is not completely flat when put on the table, this not always mean that it will not perform well and there will be loss in amplitude. Now You have opportunity to try the first new spring that You consider as damaged, and to compare the amplitudes with the old spring and with the new one, that is still in the box when the time for it to get in the barrel comes.

Edited September 22, 2024 by nevenbekriev

[NigelTufnel]

54 minutes ago, nevenbekriev said:

. It is obvious from the picture (to me) that it will catch.  If so, then You need just to close the barrel and be happy.

It will not.  It looks like it should, but when you feel it, it's totally not going to.

I understand what you mean about the spring not needing to be perfect, however this is a case where the clearance for the spring has been reduced and I'd like to improve my chances.

[rjenkinsgb]

I serviced a Soviet movement with a "T" looking spring (broken) a few weeks ago. I'd never seen one like that before.

I had a box of assorted springs & one type in it looked perfect except it had a standard end. I cut the end off the original spring, leaving it double thickness, and used that in the barrel to act as  the "step" for the outer end of the conventional spring. That works fine!

[NigelTufnel]

Hi Everyone, 

Sorry for the delay. I've spent some money on some Bergeon winders only to find myself in a bit of a pickle.  As you may recall, the new mainspring's inner coil was about 1-2 mm too large for the arbor I had, so I've been practicing tightening that coil on a spare new mainspring. 

OK, so managed to tighten it ont he arbor, I'm confident now I can take a new, off the shelf mainspring and it will wind. 

So, next step was to use a "real" mainspring winder from Bergeon so I minimize  the chance of twisting it.  Thew new mainspring is cutting the clearance in half, so want a very tidy result. 

Here's my problem, and my unnecessary expenses.  The barrel for the BERG-2729-ETA-08 is exactly 12mm wide (0.5mm too wide) , but has the right diameter winding stem.  The next step down, the 7 has a stem about 1mm smaller than my arbor and just won't catch.  So I thought, let me replace the stem on the 7 with the stem from the 8! Sadly, the 8 winding stem will not fit into the 7 winder.  This is maddening!!

What do I do? Is there another brand/line of winder I should use?  Do I just try manually winding the mainspring and go for it?

Edited October 7, 2024 by NigelTufnel