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Posted

Hi everyone. I've decided to have a go at poising since i bought a couple of different tools for the job a while back. The first one an old brass one with steel pivot rests and then a trupoise that i picked up on ebay a week later. The brass is not good at all and could do with the jaws dressing and polishing but I'm inclined not to use this at all considering the trupoise will both poise and indicate a bent balance wheel at the same time. A fantasic little gadget, the pivots rest inside set jewels so gives a very smooth run of the wheel. Just wondered if anyone else had one of these and would give their thoughts on its use. Thanks.

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Posted

all the poising tools are supposed to do something similar. They have to hold the balance wheel by the pivots and allow it to rotate with zero friction. the balance wheel is given a Porsche that's the balance wheel with roller table no hairspring and if it's perfectly poised ill role in just come to stop. Depending upon how badly out of poise it is ill role and then it will come backwards and rock back and forth until it finally comes to a stop.

at the link below to download anything that looks interesting for which is quite a bit scroll until you find Joseph School of Watch Making download the entire book but look at section 5 that has the answers you seek.

https://www.mybulova.com/vintage-bulova-catalogs#main-content

then always nice to visually see first video this is a balance wheel that desperately needs poising. You'll notice how to rocking back and forth back and forth very very bad

https://youtu.be/qstRci53nII

here's a video worries talking about poising

https://youtu.be/YifxtGqeb_s

here's an example of perfect basically. Very hard to do and for the most case is not necessary. You can still have your balance wheel slowly rocking back and forth and you still do have a Delta within 15 seconds which is fine for most stuff

https://youtu.be/mj4FymCGKHM

 

 

 

 

  • Thanks 1
Posted

With all those static poising tools you can get better results by slightly vibrating the tool. This removes the last remaining resistance. You can often find homemade serrations by filing - moving a screwdriver over it will vibrate the tool.

That is what I used for static poising, before I eventually turned to dynamic poising (static poising is good for coarse poise errors, but will still leave a small positions error).

UW1.thumb.jpg.640df4c6f49041e1f63de49575f8aa89.jpgUW2.thumb.jpg.81da25d21443c455b94157ba6f7ccc74.jpg

Frank

  • Like 1
Posted
1 hour ago, praezis said:

With all those static poising tools you can get better results by slightly vibrating the tool. This removes the last remaining resistance. You can often find homemade serrations by filing - moving a screwdriver over it will vibrate the tool.

That is what I used for static poising, before I eventually turned to dynamic poising (static poising is good for coarse poise errors, but will still leave a small positions error).

UW1.thumb.jpg.640df4c6f49041e1f63de49575f8aa89.jpgUW2.thumb.jpg.81da25d21443c455b94157ba6f7ccc74.jpg

Frank

Thanks Frank. I maybe have some more learning to do about poising and how much more beneficial dynamic is compared to static over any extra time that is involved. Your vibrating rig reminds me of a similar principle to my petrol vibrating poker i use for levelling concrete. Maybe not a good idea to use that 😕 

Posted
3 hours ago, praezis said:

before I eventually turned to dynamic poising (static poising is good for coarse poise errors, but will still leave a small positions error).

personally I find when you're dealing with American pocket watches that of 100 years of interesting things have occurred to them. I find that static poising I can easily get a Delta within 15 seconds and that's good enough. I often find if I try a dynamic poise I end up chasing my tail and things don't usually get better. In other words when you're grossly out of poise static it to really close and then if you want to be a perfectionist you can dynamic poise.

  • Like 3
Posted
10 hours ago, JohnR725 said:

all the poising tools are supposed to do something similar. They have to hold the balance wheel by the pivots and allow it to rotate with zero friction. the balance wheel is given a Porsche that's the balance wheel with roller table no hairspring and if it's perfectly poised ill role in just come to stop. Depending upon how badly out of poise it is ill role and then it will come backwards and rock back and forth until it finally comes to a stop.

at the link below to download anything that looks interesting for which is quite a bit scroll until you find Joseph School of Watch Making download the entire book but look at section 5 that has the answers you seek.

https://www.mybulova.com/vintage-bulova-catalogs#main-content

then always nice to visually see first video this is a balance wheel that desperately needs poising. You'll notice how to rocking back and forth back and forth very very bad

https://youtu.be/qstRci53nII

here's a video worries talking about poising

https://youtu.be/YifxtGqeb_s

here's an example of perfect basically. Very hard to do and for the most case is not necessary. You can still have your balance wheel slowly rocking back and forth and you still do have a Delta within 15 seconds which is fine for most stuff

https://youtu.be/mj4FymCGKHM

 

 

 

 

Two really good video examples of extremes, and Kalle of chronoglide who I've been watching since i started. The Bulova watch school catalogs also very informative and saved to my favourites. Thank you John 👍

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