Archived posting to the Leica Users Group, 2006/01/22
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]So, somebody was rich enough to biopsy one and set fire to the bit that came out - a good way for testing magnesium - take a big piece out if you forgot your flash ;-) I wonder if the airlines know that your R9s are a fire risk? Take an R9 top plate, grind thoroughly, add potassium permanganate - light the blue touchpaper and retire immediately. The French resistance used a similar mixture for sabotaging railway lines, and I'm sure nearly every schoolboy used to shave bits off his pencil sharpener too. Douglas Seth Rosner wrote: > Here 'tis friends, from the mouth - or pen - or computer of him who > knows: > > Hello Seth, > > here comes the world shaking answer: > > The top cover of the LEICA R9 is made out of magnesium alloy. It was > made out of zinc die cast on the R8. Obviously you have found a > mistake in the spec! You're the first since 2002! > > All the best and hope to see you soon! > > Stefan > > > > ----- Original Message ----- From: "Frank Dernie" > <Frank.Dernie@btinternet.com> > To: "Leica Users Group" <lug@leica-users.org> > Sent: Sunday, January 22, 2006 4:09 AM > Subject: Re: Was RE: [Leica] DSLR choice - now Zeiss-Ikon > > >> Hi Bill, >> I think the situation boils down to the difference between "good >> enough" and "the best material possible". Clearly either the >> manufacturers are lying, which I do not believe, or are convincing >> people that the materials are good enough by writing things such as >> you quote. The shell of a camera is hardly a high tech structural >> element. It is a cosmetic cover which keeps dirt out. The precision >> stuff is inside. The worst load case a camera will experience it to >> be dropped, I expect. Then who is to say what is good enough? With >> respect to Leica (almost on topic), dropped onto the top plate a >> brass plate will probably dent, a zinc (probably mazak) will dent or >> crack and so will magnesium. What actually happens depends at least >> as much on what angle it lands, what it lands on and from what >> height than the material of the shell. >> >> What I take issue with, and it irritates me a great deal, is that the >> marketing propaganda presents magnesium as new and superior. It may >> indeed meet all the criteria somebody has set for a camera - hardly >> any sort of high tech duty cycle. The fact that magnesium is >> "rugged, robust and durable" in a camera context only questionable >> in the durability sense. There is probably a hard cheese being made >> somewhere in the world which is rugged and durable enough for a >> camera shell - he joked - but I am sure you get my drift. I won't >> repeat what I have already written about magnesium but the butt of >> my concern is the durability issue. I have many Leicas. The lovely >> old black ones have "brassing". Had they been made from magnesium >> rather than brass there would be holes in them where it had >> corroded through. I have seen a magnesium helicopter gearbox casing >> from an aircraft that had been inadvisably used by its owner to land >> on his boat. At its first inspection from new the casing was scrap, >> less than 12 months old. Marinized helicopters have aluminium >> casings I believe. >> Chrome plated brass lenses I have are like new, regardless of age. >> Aluminium and brass are OK if used all the time, the wear rubs of >> oxide spots. Some of the wartime IIIc cameras have blistering chrome >> plate where the aluminium is corroding underneath. If they had been >> magnesium they would be corroded through. >> >> I have looked at a few pro photographers C*non long lenses which are >> painted magnesium too. Where they have chipped the paint off one can >> see the surface plating. As long as the bangs don't break through >> this coating they may be OK. They obviously don't care about >> longevity anyway because they change things frequently. Maybe >> magnesium can be made adequate anywhere weight is the dominant >> factor and long life is irrelevant (digicam?). Magnesium can not be >> made good, even its best alloys make it useable rather than good. >> >> If any of my engineers proposed a finishing process which -required- >> moving through 3 countries I would ask what he had been drinking. >> That would be of questionable acceptability for a high tech >> application never mind a dust cover. In the Leica case I would bet >> that is because the castings are done in France, the cameras made in >> Portugal and the QC, packaging and attachment of the "made in" >> sticker in Germany. >> >> Well Bill you and I have gone on a bit here, I ask the indulgence of >> any Lugger who has got this far. I do not doubt that magnesium can >> be made "good enough" structurally for a camera shell. I do not >> believe it can be made "as good as" any of the alternatives >> historically used - including fibre reinforced plastic. An unused >> component with perfectly applied, undamaged, surface coating MAY be >> "durable" but a used one with a surface scratched to bare metal, >> like a typical pro used camera, will not be as durable as any of the >> traditionally used alternatives. >> Frank >> >> On 21 Jan, 2006, at 18:00, Bill Marshall wrote: >> >>> Frank, >>> >>> I truly appreciate all of the information that you have presented & >>> the fact that you have lent your expertise to this discussion. >>> Thank you for your patience with me who knows next to nothing about >>> this subject other than what I can learn from reading. I'm just a >>> guy who likes cameras & who is trying to understand the marketplace. >>> >>> I certainly understand that Marketing Departments are paid to hype >>> their products & that these departments can be prone to >>> exaggeration. So, I'm not surprised when they claim that something >>> is "rugged," "durable," or "robust" & it is so only to a very >>> limited degree. However, it's certainly confusing to read about the >>> testing that Nikon & Zeiss say that they have done & to read their >>> claim that magnesium meets the highest standards of professional >>> use (Nikon's claim) in terms of resistance to corrosion & of shock >>> resistance and for this not to be true. This would be more than >>> marketing hype & exaggeration. It would be misrepresentation, a >>> blatant lie. While I certainly don't put it past the corporate >>> community to engage in such deceipt, it would be surprising coming >>> from companies like Nikon & Zeiss. I assume that Canon & Leica have >>> done similar testing although it is not explicitly stated in their >>> materials, so it only adds to my confusion when companies of their >>> stature also represent this material as strong & as fit for its >>> intended purpose. >>> >>> Some time ago, I corresponded with Hasselblad about the Zeiss Ikon, >>> specifically in regard to the magnesium body plating as well as >>> other matters. Since they couldn't answer my questions, they >>> referred me to one of the engineers at Carl Zeiss AG. In an >>> exchange of several lengthy e-mails, he assured me that they had >>> subjected the camera to intensive testing in their environmental >>> test lab for extremes of temperature, humidity, shock, and >>> vibration, that they had insisted on improvements & modifications >>> where they felt necessary, & that the camera met all of their >>> standards in this regard. The tone of his letters bore no >>> resemblance to someone from a marketing department. >>> >>> I don't know if the following sheds any light on the discussion, >>> but here is what Leica has to say on the subject in a press release >>> about the R9: >>> >>> "Magnesium is particularly difficult to manage with respect to >>> corrosion resistance and scuffing. Leica for the first time employs >>> a plasma-chemical process for coating the light metal. This >>> transforms the surface of the magnesium into a thick ceramic layer. >>> In the process, special demands are placed on the magnesium alloy >>> and on the preparation of the surface. Special lacquers are then >>> applied to achieve an extraordinarily long-lasting finish. A >>> greater fabrication effort is also required for casting the >>> magnesium in the molds because this takes place at temperatures of >>> 700 degrees C (1292 degrees F) as compared to 400 degrees C (752 >>> degrees F) in the die-casting process." >>> >>> More from Erwin Puts on the matter: >>> >>> "Magnesium is the lightest of all commercially available metals >>> with a specific gravity of 1.75. It is in itself not a strong >>> metal, nor has it good elasticity. You need to create an alloy and >>> use a considerable thickness or utilize deep sections to obtain >>> good stiffness. It is a very high cost material and does not >>> possess good corrosion characteristics. The painting and casting >>> and shaping of the topcover is a process that takes place in three >>> countries (Germany, France, and Portugal) before it ends up on the >>> R9." >>> >>> Again thanks for sharing your knowledge & for your patience with me. >>> >>> Best regards, >>> bill >>> >>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >> >> >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information >> > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > >