What do the jewels do in a watch?

[Nurburgsingh]

Slow day in the office has had me gazing hypnotically at the cogs and springs ticking away in my skeleton watch and I thought I have no idea what the jewels do..?

So... What do they do? Do all watches have them? Just automatics? Or what?

[Podie]

They act as bearings in automatic movements.

[crazy about cars]

Bling bling

[marcgti6]

Wikipedia can explain this far better than I can - http://en.wikipedia.org/wiki/Jewel_bearing

[Nurburgsingh]

Awesome... I have learned something new today.

[AndrewWF]

The jewels are all synthetic (corundum, same materials as the synthetic sapphire crystals, just a different colour) and are shaped into small dishes to hold a drop of oil which acts as the lubricant. They grow the corundum in rods and cut and polish it with lasers and heat.

[AlexWF]

AndrewWF said:

The jewels are all synthetic (corundum, same materials as the synthetic sapphire crystals, just a different colour) and are shaped into small dishes to hold a drop of oil which acts as the lubricant. They grow the corundum in rods and cut and polish it with lasers and heat.

I knew we could rely on you for some facts like this :-)

[Hoofy]

AndrewWF said:

The jewels are all synthetic (corundum, same materials as the synthetic sapphire crystals, just a different colour) and are shaped into small dishes to hold a drop of oil which acts as the lubricant. They grow the corundum in rods and cut and polish it with lasers and heat.

Kindly remove the link from your profile before I end up swapping more money for watches.

[bobbybee]

Some manufacturers use rubies, industrial grade ones and not really worth a great deal. Used as bearings as they produce far less friction than steel bearings and do not wear out as quickly.

[AndrewWF]

Hoofy said:

Kindly remove the link from your profile before I end up swapping more money for watches.

[AndrewWF]

bobbybee said:

Some manufacturers use rubies, industrial grade ones and not really worth a great deal. Used as bearings as they produce far less friction than steel bearings and do not wear out as quickly.

That's correct - like silicone, which is also being used in movements quite recently, corundum is a naturally self-lubricating substance (although a drop of oil is added for good measure).

[Miguel Alvarez]

Glad someone has asked this. My mate asked this same question assuming my geekiness would shine through and I had no idea.

[Ash 996 GT2]

AndrewWF said:

I agree, please remove the link!

[AndrewWF]

Ash 996 GT2 said:

I agree, please remove the link!

Never!

[Beachbum]

AndrewWF said:

Ash 996 GT2 said:

I agree, please remove the link!

Never!

I just spent 15mins quickly scanning that link. If I had the money, I'd be a very poor man by now. Ironically I dont have the money, so wont be spending any either

[Hoofy]

Beachbum said:

AndrewWF said:

Ash 996 GT2 said:

I agree, please remove the link!

Never!

I just spent 15mins quickly scanning that link. If I had the money, I'd be a very poor man by now. Ironically I dont have the money, so wont be spending any either

It's like arriving at the same destination but without enjoying the journey. A horological hoon.