Re: [Leica] M6 scratching film (retro?)

[DonjR43198@aol.com]

In a message dated 7/17/99 2:46:17 AM Central Daylight Time, 
garethjolly@bigpond.com writes:

<< 
Rick Casey wrote:

>The scratching happens randomly from what I can tell.  Cleaning the
>backplate religiously between reloads doesn't seem to reduce the likelihood
>of the next film being scratched.  I have always thought the backplate
>looked rather roughly machined.  So, could I please ask for a refresher on
>the best solution and if known, the batch of serial numbers that were
>causing the problem.


It is probably the pressure plate. As a number of others have done, I
recommend getting the camera repaired - which will probably mean replacing
the pressure plate.  You can't really fix it yourself as far as I can tell.
I would strongly recommend against trying to polish your pressure plate if
you were thinking about it.  Cleaning won't help.

The film scratching problem is clearly more widespread than generally
acknowledged on the LUG.

I had the pressure plate of my M6 replaced only to find that the film
scratching continued, although not as badly.

Consequently, my M6 is being replaced by Adeal. But, given it is an M6HTM, I
suspect a straight replacement may be a little difficult.

You may find that the scratches only show up on scans - not darkroom prints.
You might try that (if you haven't already) before you turf any negatives.

This question will probably bore the hell out of everybody, but of those who
had the film scratching problem, how many actually managed to get it fixed?

I know of at least one other person who had his pressure plate replaced only
to find the problem continued.

There are some suggestions that serial numbers affected are around the
2433xx mark.  Not sure how accurate that theory is, though.

Regards
Gareth Jolly



You are certainly correct that there has been a major problem with the 
pressure plates and some owners will not become aware of the problem until 
they attempt to considerably enlarge some negatives.  The fact that these 
pressure plate scratches are showing up on scanned images probably indicates 
very, very few who have these cameras are enlarging their negatives in the 
darkroom enough to notice the scratches.

You are also correct in your note that some of the Leica "acolytes" have done 
their best, including personal attacks on those who report the problem, to 
discourage the reporting of the problem.  They are doing a disservice to 
Leica users since the problem will be hidden until the truly important 
negative comes along and is enlarged.

It was reported that the quality control employee who checked the pressure 
plates became ill and the replacement worker did not catch the defective 
plates.  Probably a nonsense excuse but it shows Leica has very little if any 
quality control in place if it sells this type of merchandise and the LUG 
posts show pressure plates are not the only problem that Leica is creating 
for its customers.  Leica customers will just have to live with this type of 
very poor quality control if they want to be able to use the Leica lenses.  
Maybe the new "bean counter" at Solms will reinstall quality control as part 
of the Leica tradition.  If a $30 flat part cannot be properly manufactured 
and inspected, you can imagine the problems with the truly difficult to 
manufacture parts.  Historically, "bean counters" have had no understanding 
of precision manufacture, close tolerances and quality control, and quality 
control is the first to go down the "improved profits drain."  We shall see 
if history repeats itself at Solms.

The pressure plates from the early M series to the present M cameras appear 
to be of the same configuration so if you can find an old one it should work. 
 Sherry can buff the pressure plates to remove the offending roughness if you 
wish to go that route.  Leica MAY be able to provide properly made 
replacements.  

The major problem area appears to be the junction at which the radius joins 
the supposedly flat section of the pressure plate.  The film is gouged at 
that point and debris begins to build up there creating even deeper 
scratches.  In the poorly finished pressure plates, you may discern the 
terrible finish by dragging the junction of the pressure plate between your 
front teeth and feel the roughness.  Kind of like dragging your finger nails 
across a black board.

If no other alternative is available, a lapping operation may have to be set 
up here in the US by an independent to rectify the factory created problem.  
This would include the removal of the factory finish, lapping to a couple of 
light bands in flatness, and low microinch finish across the flat and radius 
section, and re-anodizing and coloring the pressure plate.

It is a shame there has not been a recall campaign to fix the problem.  
However, Leica quality control records may be so poor the company does not 
know when the problem started; therefore, it cannot identify the problem 
cameras.

Thank you for bringing this problem to the attention of Leica camera users so 
they may check for scratches before serious damage is done to an important 
negative.