Archived posting to the Leica Users Group, 2002/04/27
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Let me ammend myself Thermal cycking from freezing to room temp may eventually cause some settling on the shims but the castings are unaffected. Javier - --- Javier Perez <summarex@yahoo.com> wrote: > Wow! > It finally makes sense. That's why my IIIa is > smaller > than my IIIc. It's older! > > The vulcanite shrinkage has no effect on register > distance. Iron and aluminum blocks do "move around" > but that's a result of thermal cycling, chamber > pressure and cranking induced stresses, none of > which > happen in a camera. Outside of dropping, it > sometimes > happens that the camera doesn't come together > exactly > as it went apart after a CLA. That's why you are > supposed to re-mike and if necessary re-shim the > flange after every dissassembly. This was > poarticularly common with the built up chassis A's. > It's the same thing that happens when you pull the > cam > carriers on a 907! The aluminum shrinks.... > Javier > > --- John Collier <jbcollier@shaw.ca> wrote: > > I finding this all a bit much to believe. Iron and > > aluminium castings > > contract significantly over time?! Seasoned engine > > blocks are not any > > smaller than brand new ones. Certainly engines do > > not seize up over time > > due to the cylinder diameter shrinking; even over > a > > hundred years! > > Seasoned engine blocks have been vibrated by > > operation of the engine and > > this stress relieves the material of the block. > That > > is it and not > > something you want to do to your camera. > > > > Can LTM Leicas have film register problems > overtime? > > Yes but it is due > > shrinkage of the cover material on the first > bodies. > > The lens mount is > > screwed onto the body sandwiching the cover > > material. Owners notice that > > their lens flange has "loosened" and tighten the > > screws which puts the > > mount out of proper register. This happened very > > quickly with the > > special order leather finishes but very slowly > with > > the vulcanite > > material. > > > > The most common cause of the mount being out of > > register is from an > > impact. > > > > John Collier > > > > On Saturday, April 27, 2002, at 09:47 AM, > > dante@umich.edu wrote: > > > > > Leica late LTM (IIIc and > > > on) and M bodies contract over time, enough to > > cause the body focus to > > > change. > > > > -- > > To unsubscribe, see > http://mejac.palo-alto.ca.us/leica-users/unsub.html > > > __________________________________________________ > Do You Yahoo!? > Yahoo! Health - your guide to health and wellness > http://health.yahoo.com > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html __________________________________________________ Do You Yahoo!? Yahoo! Health - your guide to health and wellness http://health.yahoo.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html