Aneroid Barometer Question

[Schaferhunde]

I wondered if anyone knows how the square pin comes out to release the bellows spring, I want to remove the bellows spring to treat the spider rust. The Barometer dates 1850.
All help would be greatly appreciated.
Maybe this square pin is threaded hence the square?

 

[leeinv66]

It's been a while since I worked on one of these, but I thought it was the spring tention that held that pin in place. Can you not depress the spring and pull the pin out?

 

[Schaferhunde]

It's been a while since I worked on one of these, but I thought it was the spring tention that held that pin in place. Can you not depress the spring and pull the pin out?

You could be right, I will try again but why use a square pin?

 

[Schaferhunde]

You could be right, I will try again but why use a square pin?

The square pin is not threaded and by compressing the leaf spring I have moved it into the centre post off the right top of the spring.
Its really hard to pull out, I had to use a tiny drift and matching hammer to move it that far. Why use a square pin, I think its to push the pin in with a flat side down, then rotate it onto its edge to apply more pressure, and hold it in place.
I missed the boat here initially and will make a tiny spanner to fit across the flats and hopefully rotate it? The hole is round.
IS THERE A COMPRESSION TOOL FOR THESE SPRINGS?

 

[Schaferhunde]

The square pin is not threaded and by compressing the leaf spring I have moved it into the centre post off the right top of the spring.
Its really hard to pull out, I had to use a tiny drift and matching hammer to move it that far. Why use a square pin, I think its to push the pin in with a flat side down, then rotate it onto its edge to apply more pressure, and hold it in place.
I missed the boat here initially and will make a tiny spanner to fit across the flats and hopefully rotate it? The hole is round.
IS THERE A COMPRESSION TOOL FOR THESE SPRINGS?

 

[Willie X]

Is it working? If so, it would be a good idea to leave it as is. Willie X

 

[Schaferhunde]

Is it working? If so, it would be a good idea to leave it as is. Willie X

The bellows are sealed and move the needle on compression but the chain links have some rust spots as the spring does. It needs to be stripped cleaned and oiled, then regulated. It was never working accurately.
I'll set up a spring compression device to finishing pulling out the square pin, I think the pin was inserted on its edge which is how I'll remove it..

 

[Schaferhunde]

Pin removed spring released without damage. Interesting the hole for the pin is diamond shaped to take the pin shape.

 

[Schaferhunde]

Is there anything on calibrating an old Aneroid, not the screw at the back, but on my Naudet its quite complicated with a no. of adjusting screws. I have re assembled it after cleaning, polishing oiling etc.
Pic to follow.