On 27 January 2015 at 06:20, wrote: > > > the auditor reckoned we were > > > only about half the lumens he reckons we should have. He wants us to > > > > > > have 1000 lumens for working at the assembly and inspection > benches. > > > > > How > > > many lux at work surface? > > > > I think he is looking for 1000 lux at the work surface, but I wasn't > > > involved in the discussion. > > > > I'd hazard that that was 'unnecessarily bright" > > > I have found that illumination levels far below what are traditionally > claimed > > are needed *seem* [tm] to be adequate in many cases. > > Yeah, but this is for assembly of electronics modules for space > instrumentation, where everything gets 100% inspected - except the PCB > while that is itself being manufactured! > With surface mount components getting smaller, and x-ray inspection > looking for voids in a solder joint, and ... and ... you name it, some > other guy is going to say it's not up to scratch. > It seems ESA has had some scares with surface mount component assembly, > and have a solder verification process document that > .... > , but some of it is so way over the top ... > > I spent some time on several visits to China with a Canadian who has extensive manufacturing experience and who now rides shotgun on contract manufacturing for his various clients. He is highly focussed on soldering quality and carries a large and heavy inspection microscope in his luggage. (Probably larger and heavier than my cameras :-) ). I generally find that if I use a "really bright light" and something like 10 dioptre of lenses + a typical 'bench magnifier' (ie over over kill) that even highly acceptable soldering looks "really ugly at best" and anything liable to be problematic looks something like a high speed car crash. eg I've seen smd legs/pads that looked entirely OK to my eye with normal close-viewing-correction lensing (say 2-4 dioptre range) that look more like a hoverboard floating above a surface with enough light & magnification. So I can appreciate what your inspector is trying to achieve. Maybe properly managed 1000 lux would be nice :-). R --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .