Mainspring slipping in barrel violently

[Pete1991]

So I am servicing an ETA 2783. I have put a dot of moebius 8212 before the cutouts on the barrel wall, then put in a new mainspring. When I wind the watch with the crown it becomes stiffer and stiffer then eventually slips making a loud noise. Amp dosent seem to drop below 250. I have attached a video incase it helps.

[LittleWatchShop]

I just worked through this issue with a waltham 6/0.  My issue was that the mainspring end was a double bridle with hole (T style).  It was not installed correctly.  When installing the spring, I had to line everything up before releasing the spring into the barrel.  Only then will the T posts line up with the slot in the bottom of the barrel.  Finally, the slot in the cover lines up as well.  Once getting that right, it stopped slipping.

There is another thread on the Ega 2783 mainspring.  It may well use a double bridle spring and thus it could be your problem

 

[Pete1991]

2 minutes ago, LittleWatchShop said:

I just worked through this issue with a waltham 6/0.  My issue was that the mainspring end was a double bridle with hole (T style).  It was not installed correctly.  When installing the spring, I had to line everything up before releasing the spring into the barrel.  Only then will the T posts line up with the slot in the bottom of the barrel.  Finally, the slot in the cover lines up as well.  Once getting that right, it stopped slipping.

There is another thread on the Ega 2783 mainspring.  It may well use a double bridle spring and thus it could be your problem

 

Sorry, I should have mentioned it's an auto so it's supposed to slip somewhat.

[Nucejoe]

22 minutes ago, Pete1991 said:

Sorry, I should have mentioned it's an auto so it's supposed to slip somewhat.

ETA2873 is auto. 

How many turns of the crown or ratchet wheel would you say it holds power? 

When it slips and is presumably fully dispowered; Wind and count number of turns at which it discharges. You would have a number.

Rewind and stop just short of discharge( the number you have).

Bench test how long it runs, thats how much your actual power reserve is.

Compare with the nominal power reserve( 47 hrs). you then know where you stand.

Regs

Joe

[Nucejoe]

Sorry I meant ETA2783 is auto. 

Mainspring it to wrap around the barrel arbour tight, if it loose, the arbour catch can disengage.

[Pete1991]

2 hours ago, Nucejoe said:

ETA2873 is auto. 

How many turns of the crown or ratchet wheel would you say it holds power? 

When it slips and is presumably fully dispowered; Wind and count number of turns at which it discharges. You would have a number.

Rewind and stop just short of discharge( the number you have).

Bench test how long it runs, thats how much your actual power reserve is.

Compare with the nominal power reserve( 47 hrs). you then know where you stand.

Regs

Joe

Hi Joe, I can turn it a good few times then it makes tha loud clicking noise. It looses amplitude but about 50 degrees then a few seconds later climbs back to a normal level.

[Nucejoe]

23 minutes ago, Pete1991 said:

Hi Joe, I can turn it a good few times then it makes tha loud clicking noise. It looses amplitude but about 50 degrees then a few seconds later climbs back to a normal level.

Partial power discharge is either due to faulty click or inadequate friction between springs spindle and barrel wall or barrel arbour catch and mainspring eye disengage.

If mainspring is too strong it can kick back the click spring, keep in mind the click is suppose to release excessive torque/wind in this design.,,,, Ink mark winding wheel and ratchet wheel where they come in contact across each other, wind to force a power discharge, then check the two dots, if both dots are still across from each other, discharge happens inside the barrel.

I hope you can understand my broken english.

[Pete1991]

8 minutes ago, Nucejoe said:

Partial power discharge is either due to faulty click or inadequate friction between springs spindle and barrel wall or barrel arbour catch and mainspring eye disengage.

If mainspring is too strong it can kick back the click spring, keep in mind the click is suppose to release excessive torque/wind in this design.,,,, Ink mark winding wheel and ratchet wheel where they come in contact across each other, wind to force a power discharge, then check the two dots, if both dots are still across from each other, discharge happens inside the barrel.

I hope you can understand my broken english.

Hi Joe, no your English is great, no need to apologise. I have ordered a new mainspring just to be sure. The discharge appears to be happening inside the barrel. I experimented with a little bit more grease and it lessened the slipping somewhat. I have ordered a stronger breaking grease and I hope this will solve the issue 

[JohnR725]

5 hours ago, Pete1991 said:

I have put a dot of moebius 8212 before the cutouts

the problem here is you need to figure out where it's slipping on the arbor or the barrel wall.

then there is the other problem each of the types of breaking grease have slightly different characteristics and quantities of application. for instance I've seen an online YouTube video using the Rolex grease and to me it seems like a super excessive quantity is applied to the barrel wall.for that particular grease that is the recommended quantity. On the other hand the way you applied it sounds like you should have been using the lubrication found below. It is placed as small blobs exactly as you describe. This stuff is really really sticky sounds like yours is not a sticky so it's slipping prematurely and not holding when it does slip.

 

https://www.cousinsuk.com/product/kluber-chronogrease-p125