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Posted

I know it's far from perfect, but nevertheless.. for a first attempt at making something resembling a balance staff..it could have gone worse..

So I'm happy and I wanted to share this and say thanks for everyone on this friendly forum for sharing their knowledge. Much appreciated!!

It's small. I used 1.2mm blued steel. The cheap hand gravers @nevenbekrievĀ mentioned (Thnx Nev!) performed like advertised.

Having your lathe under a microscope makes it easier as well.

20240915_220057.jpg

20240915_213942.jpg

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Posted

I am so glad to see someone doing so well. Actually, it looks almost perfect.

I feel I need to explain the purpose of some things in the balance staff so when somebody knows this things, then they will be made better.

The first thing here is the shape of this part, pointed with red arrow.

Untitled.png.9a40b63fd23ca8db5a2d26ac23061a8c.png

Ā 

The figure shows the order of actions when staff turned between still centers in old fashion swiss turns. But no matter, this is the same in all other ways of turning staff. You see the part pointed with red in previous image 'Š·' is cylindrical, and then it is conical in 'Šø'. And the cone hereĀ  is reverse oriented against the pivot. It is done with one only purpose - to prevent the oil from climbing down (or up) the staff and keep it where it should stay - on the thin cylindrical part of the pivot. But to be such function possible, most important is at the end, the edge, pointed with green at the last image, to be sharp as knife. This sharp edge is formed by two surfaces - they both must be conical and prefectly polished. In the good quality old movements, the staffs have such part on both sides, not on upper side only.Ā  But in simple staffs, again, the edge has to be sharp as knife, no matter there is no reverse oriented cone.

In modern watches with antishock devices, this reverse cone has disappeared due to the design of antishock system, and, may be it is found that it's presence is not that important as old watchmakers believed, but the sharp edge and polished surfaces is still something obligatory.Ā 

The pivots of You staff need some more attention - the common rule is that the cylindrical part must be long 3X it's diameter. But, have in mind that sometimes in old (130+ years) movements, the pivots have to be longer. The pivots of You staff are much longer than needed, but this is something that will come in place with the practice.

And, the internal angles must be sharp too, now the roller will may be not go to the end as the angle there is not sharp. Again, some practice will make things perfect. As for first attempt, the staff shown here is more than ideal. Believe me, I have seen a lot first attempts and know what I am talking.

Ā 

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Posted
14 hours ago, caseback said:

I know it's far from perfect, but nevertheless.. for a first attempt at making something resembling a balance staff..it could have gone worse..

So I'm happy and I wanted to share this and say thanks for everyone on this friendly forum for sharing their knowledge. Much appreciated!!

It's small. I used 1.2mm blued steel. The cheap hand gravers @nevenbekrievĀ mentioned (Thnx Nev!) performed like advertised.

Having your lathe under a microscope makes it easier as well.

20240915_220057.jpg

20240915_213942.jpg

Well done caseback, I'm looking forward to my first, not quite ready.......to embarrass myself šŸ˜…

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