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Author Topic: Reflecting surface falling off from mirror - Bad mirror? Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 11-29-2006 04:02 PM                     I installed new mirror in lamp house with Meopta 380mm diameter mirror and XBO2500 i vertical position. After 15-20 min of working I notticed that about of couple of centimeters silver reflecting surface was gone from mirror, it was fall of easily and after next 20 minutes of working about 30% of mirror was damaged.....lamp house has small mirror as well and cooling fans! I spoked with dealer who sold me this and he told that may bee i miss aligned small mirror (so the light is striking the big mirror - but If I miss aligned the I think less light will strike big mirror than was aligned?) but everything is properly aligned because on another projector is same XBO, with same mirror, lamp house, fans.....and everything is OK! And in all places i worked with this mirrors I newer had problems. This mirror isn't produced anymore and I think this one is made in 1986....so maybe after long storing time this could happen? Opinions, ideas.....????  |  IP: Logged Cameron Glendinning Jedi Master Film Handler Posts: 845 From: West Ryde, Sydney, NSW Australia Registered: Dec 2005 posted 11-29-2006 04:56 PM                     I think its time to get it resurfaced, If its not a kinoton style of mirror which is very different, a regular mirror shop might be a good place to ask where to get it done, only if you have a spare, otherwise a new one is needed. Personally I am confused by your suppliers comments as I personally have never seen misalignment do this. mirrors do wear out over time due to heat ect.  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 11-29-2006 06:13 PM                     quote: Cameron Glendinning Personally I am confused by your suppliers comments as I personally have never seen misalignment do this. mirrors do wear out over time due to heat ect. Not only You are confused with it.....  |  IP: Logged Jonathan Bodge Film Handler Posts: 83 From: East Dorset, VT Registered: Nov 2006 posted 11-29-2006 06:43 PM                     Hi there Marin, Question, how come the original mirror was replaced? Also, if the mirror (which isn't cheap) has a manufacturing (coating) defect do you really think the dealer would admit it? I have collectors (mirrors) in the field, same brand, some flake (over 5 years) and some don't. Your situation seems unusual.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 11-29-2006 08:14 PM                        Jonathan; it really isn't up to the dealer. With single digit markups, the dealer can't afford to "eat" anything that expensive and the factories usually don't cover that problem after a certain time....30,60,90 days. This problem is made worse if your dealer actually stocks parts; they may have been on the shelf for months or a year. Louis  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 11-30-2006 07:00 PM                     A bi mirror system lamp focus is very critical The small auxilary front mirror must produce a inverted image f the arc inside the electrode gap in the same exact plane (the small aux mirror is a spherical curve compared to the main reflector being elipical) If it is focused so the image is on the electrodes they will be burned off faster than one blinks If focused onto the main reflector it will scale  |  IP: Logged

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