Archived posting to the Leica Users Group, 2007/05/24

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Subject: [Leica] Report of M8 Base Failure
From: shino at panix.com (Rei Shinozuka)
Date: Thu May 24 08:44:56 2007
References: <052420070456.21359.46551B13000EF11D0000536F219791336303010CD2079C080C03BF970A9D9F9A0B9D09@mchsi.com>

of course you are correct; and IANASE (I am not a structural engineer).  
at first glance the m8 failure reminds me of some of the failures described
in the entertaining book "why buildings fall down: how structures fail"

http://www.amazon.com/Why-Buildings-Fall-Down-Structures/dp/039331152X

there are descriptions of how a structure may be soundly designed, but 
then some seemingly innocuous change (such as substituting a single 
load-bearing rod with two rods) makes the structure unsound.

professor salvadori, the primary author, was an eminent civil engineering
scholar and my father's phd advisor at columbia.

-rei

On May24 04:56, grduprey@mchsi.com wrote:
> Rei,
> 
> I'm not sure that one or even two failures constitutes a design flaw.  I 
> would lean toward a bad casting at this point.
> 
> Gene
> 
> -------------- Original message from Rei Shinozuka <shino@panix.com>: 
> -------------- 
> 
> 
> > that's kind of horrifying to see the metal housing of the m8 
> > fail so catastrophically. i guess the design is faulty; 
> > the front-back split effectively means that the baseplate 
> > sort of hooks into a lower corner of the front piece. a 
> > one-peice design would not fail in this manner. 
> > 
> > it's hard to imagine there was much stress on a tripod--the 
> > lens it was mounting was only a 50 lux, rather than 
> > a heavy noctilux or 75 lux. 
> > 
> > at least the lens didn't look like it was damaged in the fall 
> > 
> > -rei 
> > 
> > On May23 19:00, Robert D. Baron wrote: 
> > > This report on the LUF regarding failure of the base of an M8 is 
> > > perhaps 
> > > of some concern: 
> > > 
> > > 
> > http://www.l-camera-forum.com/leica-forum/leica-m8-forum/25121-base-plate-failur
> >  
> > e.html 
> > > 
> > > or 
> > > 
> > > http://tinyurl.com/2m9kdx 
> > > 
> > > I am not a metallurgist nor do I play one on tv. I have no idea if 
> > > this 
> > > is a rare event or something to fret over. 
> > > 
> > > I looked at my own base and it looks fine (solid, it appears) but what 
> > > do I know? 
> > > 
> > > 
> > > 
> > > --Bob 
> > > 
> > > _______________________________________________ 
> > > Leica Users Group. 
> > > See http://leica-users.org/mailman/listinfo/lug for more information 
> > 
> > -- 
> > Rei Shinozuka shino@panix.com 
> > Ridgewood, New Jersey 
> > 
> > 
> > _______________________________________________ 
> > 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

-- 
Rei Shinozuka shino@panix.com
Ridgewood, New Jersey


In reply to: Message from grduprey at mchsi.com (grduprey@mchsi.com) ([Leica] Report of M8 Base Failure)