Archived posting to the Leica Users Group, 1999/01/07

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: Re: [Leica] LEICA - M DRIVE
From: TTAbrahams@aol.com
Date: Thu, 7 Jan 1999 20:19:04 EST

On 1/7/99 wooddar@MLE.CO.UK (Wood, Darrell (London) wrote:
>To all,
>There is a rumour that Leica plan to bring out a redesigned M Drive to
>compliment the TTL is this true?. I had thought of going for the existing
one.
>P.S.
>It must be possible for them to make a smaller one and quieter.  
>It has also even been suggested that they might buy back the patent I
>believe they sold to Tom Abrahamsson, and produce a resigned Leicavit.
>Many Thanks 
>Darrell


 I don't think that Leica is coming out with a new power winder for the M6TTL,
at least not in the foreseeable future. The current version of the power
winder is still available and, according to Leica Solms, it is not a very good
seller. I have tried all of the variations of this winder and it is too big,
too noisy and too expensive (for what you get!). If they designed a smaller,
lighter version, about the size of my Rapidwinder with a 3-4 frame/sec
capability and at a competitive price, it would be nice. A long time ago I was
toying with the idea of making a power winder that would fit inside the
housing of the Rapidwinder and be powered by 2 AA batteries. The modern
miniature electric motors are quite amazing, just look at the power plants for
small radio controlled cars, some of the electric motors available for Lego
kits, etc. The main reason for not pursuing this venture was a/ I don't really
like power winders and b/ a bit of concern was registered on the faces of the
people from Leica when I proposed it!
 I don't think that Leica ever had a patent on the Leicavit - the name was
trade mark registered, but the design of the winder was not unique - only
germanically complex - they used 51 different parts in the Leicavit - I use 7
parts and 3 springs for the drive train. The housing of the Leicavit was made
from the same 0,8mm thick brass as the top plates were made from. The entire
drivetrain was attached to the inside cover plate with screws and the housing
had an alarming tendency to dent and flex. The clutch on the original Leicavit
and Leicavit MP was a single action clutch - if you pulled the lever halfway
across the base and wanted to "double stroke" the camera (handy when you are
shooting verticals) you had to advance the lever back to the position were you
stopped on the preceding stroke. For many years I used M2's and MP's with the
Leicavit and when I set out to make my own version of it, I knew what I did
not want and what it should be. The Rapidwinder is not perfect. I am
continuously upgrading and revising the design within its housing. One of my
benchmarks for the design was simplicity - the user should be able to adjust
or repair it if something went wrong. I also had to keep the design criteria
such that I could make it myself in the beginning and as time went by, I could
farm out certain parts for CNC machining. It is still a handmade winder,
almost everything in the drivetrain is made by me and of course the assembly,
adjusting and checking it out is also my job. 
 One day I am sure, Leica will make a good winder for the M - but until then I
will continue providing my "niche" market Rapidwinder for those of us who like
to advance the film with our left hand, focus with our left eye and never have
to worry about batteries or Y2K.
Tom A
Tom Abrahamsson
www.rapidwinder.com