**** Have you cracked under the pressure ****

[Strela167]

Would have thought a crack not crazed. The '67 earlier models had a similar problem, split the plastic not crazed all over though. Could it be a chemical reaction perhaps. Perspex is not used in the food industry due to the cleaners used afaik..

[is that my watch]

There could be a temperature difference, if the top of the wardrobe is only a few inches and a sheet of plaster-board from the roof space.

bout a foot and half from the floor of the loft.. pre second world war house they are if honest fridges in winter and saunas in the summer

[is that my watch]

Would have thought a crack not crazed. The '67 earlier models had a similar problem, split the plastic not crazed all over though. Could it be a chemical reaction perhaps. Perspex is not used in the food industry due to the cleaners used afaik..

well polywatch was used so that should not have cause it my thought was that if existing fault when I polished it it cause more pressure on it then even a small amount of cold difference might have been enough to do the deed

[Strela167]

well polywatch was used so that should not have cause it my thought was that if existing fault when I polished it it cause more pressure on it then even a small amount of cold difference might have been enough to do the deed

http://www.clearlyacrylic.com/plasticcare.html

been in the dishwasher

[skywatch]

I"ve had this happen, but not in 2-3 months. I put a watch into the vault at the bank for a year or so, and when I retrieved it, it had the same stress cracks. Watchmaker explained that plastic crystals dry over time and lose their elasticity. They even shrink a little. So depending on which mounting system design the crystal is, stress causes the cracks to appear as the crystal becomes more brittle over time. No idea why yours happened in such a short period, though.
Had the opposite problem recently. The crystal on my vintage Omega just fell out one day. It had dried and shrunk over the years until it was just too small to stay in place.

well polywatch was used so that should not have cause it my thought was that if existing fault when I polished it it cause more pressure on it then even a small amount of cold difference might have been enough to do the deed

I think Sherry's comment mirrors my own experience best. In my various attempts to refurbish old watches, I find that acrylic crystals get more brittle with age - I believe mostly because oxidation and ionizing radiation (i.e. sunlight) can break the longer more structural polymer chains into smaller chains, making the plastic less pliable. Certain crystals are under more pressure in the case due to design - tight fit = better water seal, etc. That pressure can simply result in crazing over time as the brittleness increases. In other words, it might have had nothing to do with being in your drawer, it may have just been due time.

[is that my watch]

I think Sherry's comment mirrors my own experience best. In my various attempts to refurbish old watches, I find that acrylic crystals get more brittle with age - I believe mostly because oxidation and ionizing radiation (i.e. sunlight) can break the longer more structural polymer chains into smaller chains, making the plastic less pliable. Certain crystals are under more pressure in the case due to design - tight fit = better water seal, etc. That pressure can simply result in crazing over time as the brittleness increases. In other words, it might have had nothing to do with being in your drawer, it may have just been due time.

hmmm yes and hmmm no yes alot of what you say of age and the like yes but got some really old one with great condition crystal but depending how much use they had I suppose as contact with heat / light /uv rays could differ

but this was a pocket watch conversion so could not have been old enough for this process to have taken place maybe here it is again

[is that my watch]

http://www.clearlyacrylic.com/plasticcare.html

been in the dishwasher

funny thing is the more I think of it at the time of noticing the scratch I think I said at the time I did not know how it happen so the weakness may have always been there or the flight from russia to the uk when bought did it in with the cold of a luggage bay ?

[Strela167]

funny thing is the more I think of it at the time of noticing the scratch I think I said at the time I did not know how it happen so the weakness may have always been there or the flight from russia to the uk when bought did it in with the cold of a luggage bay ?

There was a thread elsewhere about an ebay seller loophole saying the same flight getout

Would put this down to a badun getting through

[is that my watch]

There was a thread elsewhere about an ebay seller loophole saying the same flight getout

Would put this down to a badun getting through

well had them say once about a watch seizing up because of the cold had frozen the oil but this was a new one on me but had the sbs appear with a scratch one time that I never saw before or how it got there either maybe one of the family are wearing them on the sly might have to booby trap my watch draw

[skywatch]

....but this was a pocket watch conversion so could not have been old enough for this process to have taken place maybe here it is again

... or as they say in the car adverts, "your mileage may vary."

If it's a PW conversion then perhaps the builder installed the crystal under too much pressure?