Balance wheel tilting

[Khan]

Hi

The balance wheel stops because when it's running, it's not horizontal from side view and touches the pallet fork bridge by tilting. It's a EB 8021 movement. There seem to be enough end-shake. I replaced the staff by the way, but it should be aligned when pitted back together. The wheel is flat when trying to twist it, so the balance jewels are not damaged. 

[JohnR725]

2 hours ago, Khan said:

The balance wheel stops because when it's running, it's not horizontal from side view and touches the pallet fork bridge by tilting. It's a EB 8021 movement. There seem to be enough end-shake. I replaced the staff by the way, but it should be aligned when pitted back together. The wheel is flat when trying to twist it, so the balance jewels are not damaged. 

your paragraph is confusing? If it's not parallel and touches the plates there is a definite problem. But if it's also flat when you twist it that indicates that it's parallel which conflicts with the first statement you had that it's not parallel?

So when restaffing a watch before you put the hairspring on it before you put the roller on you put the balance wheel with its new staff in to make sure it spins nice and that it is running parallel and not wobbling was that something that you did? Then once you verify that it looks right then you can put the rest of the stuff on like the roller table next to verify that it engages with the fork then finally the hairspring.

also watches like this specifically pin lever watches are made the price. So even though they have screws and can be disassembled there really really cheap and they're going to have issues.

also in your photograph I can see the lower pivot of the balance staff but I can't see the upper because they hairspring is blocking it. So perhaps put the balance wheel back in the watch the bridge back down and a sideways pictures so we can see what that looks like.

 

 

https://17jewels.info/movements/e/eb/eb-8021-68/

[clockboy]

Agree with John, I suggest you go back to the basics, remove the mainspring and roller table & check it spins freely without any wobbles. 

[Khan]

Hi

Thanks for informative replies. I see I need to acquire a truing caliper to check the wobbling. This was my first attempt to  re-staffing, so appreciate the feedback. Here are some pictures as required. Yes, these movements are cheap and containing brass here and there and can be damaged and scratched easily. 

Edited May 6, 2020 by Khan

[JohnR725]

the good news is I can see the pivots and they look straight and they're still there.

Something that I can't see is what does the balance staff originally look like? then did you physically compare the original staff with the replacement staff? 

then there's something is bothering me but looking at the close-up I'm not quite sure? Normally the roller assembly would be tight against the hub and you have a gap? But having not seen the original staff it may be tight against something it may be exactly where it's supposed to be.

So the next picture would be put the balance wheel in the watch without they hairspring and see if the balance wheel turns and of it that some weird angle get a picture for us

[Khan]

Hi John

Thanks again for taking time - great feedback. The replacement was an original - Yes, it has an extra shoulder making a gap between hub and roller. Attached picture is another attempt of staffing, as I somehow broke a pivot on previous one, it seemed weak though...I had various staffs and chose one closest to the size. The pivots were thicker, so I "filed" them thinner with a fine stone. The wheel is more balanced and not touching anything anymore, but the wheel doesn't turn, I think the pivots are tightening against the jewels. Anyways, a complete balance replacement might be easiest. I considered this as a fun project to practice on. But cheap movements are fragile and clumsy to repair!

Edited May 7, 2020 by Khan

[JohnR725]

3 hours ago, Khan said:

"filed" them thinner with a fine stone.

when you modified them with the fine stone did you do this by hand? Or did you have access to a watchmakers lave?

then staffing a watch is usually not a beginner's task. That's because you need to understand a whole bunch of stuff  basically have a really good understanding of how the balance wheel works in the watch so if it's not quite right it makes it a lot easier to grasp what's going on. Then depending upon the watch the replacement staff will have issues. For instance American pocket watches lots of variations for the same staff number. Or pivots they came in a whole variety of sizes. Or replacement staffs that are made larger on the grounds of the watchmaker will shrink things to fit. This would include things like the length of the pivots being too long. So you have to bill understand how to shorten the pivots properly.

so unfortunately it means changing a balance staff is not a plug-and-play operation and is going to work perfect in every single incidents there will be times that does happen and other times you're going to have to fit the staff. This is where a watchmaker's lathe comes in very handy.

 

[Khan]

Thanks again for sharing great knowledge! 

I filed the pivots by hand. Quite paranoid situation, as I was always afraid to file too much.

I did another experiment on another watch cal. Urofa 58 but the ordered staff had exactly same size hub as the whole in the balance wheel. The old staff had bigger hub. In such case, I guess the staff is useless? 

By the way, I did both the dismantling and assembling of the staff by a staking set and not a platax tool. Is it no go? I noticed the wheel can bend if punching too hard. 

 

[JohnR725]

15 hours ago, Khan said:

I filed the pivots by hand. Quite paranoid situation, as I was always afraid to file too much.

I did another experiment on another watch cal. Urofa 58 but the ordered staff had exactly same size hub as the whole in the balance wheel. The old staff had bigger hub. In such case, I guess the staff is useless? 

By the way, I did both the dismantling and assembling of the staff by a staking set and not a platax tool. Is it no go? I noticed the wheel can bend if punching too hard. 

the normal procedure when changing a balance staff is to attempt to figure out and secure a replacement staff. We will note I'm giving you the ultra short version because some watches will have a lot of very options for staff even with the same part number. This is typical on American pocket watches. Then once you have the replacement staff it's important to measure not just visually look at it but measure the old versus the new. This will avoid any unpleasant surprises.

If the new staff needs to be modified like the pivots are too big it's always best to do that before you put it in the balance. Often times replacement staffs will be bigger than they need to be so the watchmaker can reduce things to fit. usually the pivots are too big and need to be reduced in diameter sometimes shortened. Occasionally the entire staff is physically too big but that is usually an aftermarket staff.

staking set works fine it's the classic tool to take out and put in a balance staff but you do have to understand what you're doing and how to do it otherwise problems will occur.

at the link below you want to scroll down to the section titled "Joseph School of Watch Making" it would actually be better to have a physical book or the complete PDF but in the absence of that the website version can be used some stuff isn't quite complete though.

so for instance section 4  explaining how to refinished pivots with a variety of techniques. But if you're putting in a balance staff the same methods will work for reducing the diameter the staff and shortening the staff.

so whole bunch of chapters on balance staff replacement you might find it helpful to read some of this

https://www.mybulova.com/vintage-bulova-catalogs

 

 

 

 

 

[Klassiker]

Is it me, or is the entire balance cock in that last photo crooked?

[nickelsilver]

6 hours ago, Klassiker said:

Is it me, or is the entire balance cock in that last photo crooked?

Looks that way to me too, and looks like a couple of screws coming in from the dial side a bit too far and possibly interfering with the cock?

[Nucejoe]

You can take the fork out and test the balance wheel inside the watch for wobble.

[Khan]

Thanks to all for replies. The balance wheel sits quite high on this movement, so the screws from dial side doesn't touch. The balance cock looks crooked because I might not have pressed it down correctly. 

[Nucejoe]

Begining to wonder if pivot is inside the jewel hole.

[Nucejoe]

You may have inserted a wrong staff in.

[JohnR725]

5 hours ago, Nucejoe said:

You may have inserted a wrong staff in.

 

5 hours ago, Nucejoe said:

Begining to wonder if pivot is inside the jewel hole.

 

On 5/7/2020 at 10:35 PM, Khan said:

I filed the pivots by hand

maybe be best to go back to the beginning like where did the staff come from? Did you compare the new staff to the old staff preferably with a measuring device not just your eyes?

then what was the perceived problem that required filing the pivots by hand?

I looked up the staff cross references back to the base model of 1553. I have a complete list of all the watches that use this staff. Also website below they sell balance staffs but more important they give dimensions. Also the bestfit book has dimensions I snipped out that image the numbers all agree so that should be the size of your staff.

 

100/1659     
Factory Number:STAFF/BET 1553

BET 1553
BET 1554
BET 1579
BET 1605
BET 8020
BET 8020N
BET 8021
BET 8021-68
BET 8022
BET 8022N
BET 8023
BET 8024
BET 8025
BET 8027
BET 802IN

https://www.balancestaffs.com/eb.php

[Khan]

I filed the staff by hand because the pivots were too thick for the jewel holes. I only measured by eye. The staff came from an unsorted group of staffs I have in stock. The hub diameter and height matches pretty much. But the pivots dimensions were different. I think there is much more theory into it that I should discover. I appreciate all the help provided in this forum. Thanks again!