Graphlex Rapax shutter exercise?

"Pete" wrote in message
...
I have a nice Crown Graphic that I'm thinking of selling
due to the high
cost of Polaroid, which is really what I had bought it
for.

The only problem I have with it is this:
The Rapax shutter works fine, except that the 1 and 1/2
second speeds become
sticky and hesitant if not exercised regularly. Once a
week seems enough...
and, when they do hesitate, just tripping the shutter
several times before
using it cures it. I'm just wondering how severe one
should consider this
problem, and what can be done about it?

Pete

I answered this via Google groups last night but don't
see my answer in the thread so will repeat it. The Graphex
shutter is the same as the Wollensak Rapax shutter. These
are good shutters. The slow speeds are off because the
lubricant on the retarder escapment has become gummy. While
a good cleaning is the ideal way to deal with this a couple
of drops of Naptha on the gears of the retarder will
probably bring it back to life. Ronsonol ligher fluid is
pretty pure naphtha and easily available. To get at the
clockwork you must remove the front cover of the shutter.
This is done by unscrewing the front lens cell (I would also
take out the back cell). Under the cell is a chrome ring
which holds the front cover in place. Unscrew this. A grip
made of a latex rubber glove will help. The mechanism is
pretty obvious once the cover is off. Use a small brush to
apply the naptha so it goes where you want.
There are several shutter repair people who work on
Wollensak shutters. All of them use hair springs so its not
too difficult for a skilled person to make new springs when
necesasry. When the main drive spring becomes fatigued it
affects the higher speeds, not so much the low speeds, that
is almost always due to congealed lubricant. Excercizing it
will not cure it. Eventually it will stick. It really needs
to be cleaned. Modern lubricants are synthetics which don't
oxidize and gum, or at least not for many years.
If you _really_ want to get into this shutter you can get
a factory repair manual from John S. Craig at
http://www.craigcamera.com
The Rapax/Graphex was designed partially because the
Kodak Supermatic did not work well with flash synchronizing
solenoids. The Rapax/Graphex has a lighter "trigger pull" or
push, to trip it plus the force is constant with the shutter
speed. Also, the built-in sychronizer does not require
separate cocking as it does on the Supermatic. When tuned up
properly these are quite accurate and reliable shutters.
Unfortunately, some of the Wollensak lenses that come in
them are not wonderful.
Welcome to the Graphic club. They are hard to put down
once you get used to the thing.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Pete" wrote in message
...
I have a nice Crown Graphic that I'm thinking of selling
due to the high
cost of Polaroid, which is really what I had bought it
for.

The only problem I have with it is this:
The Rapax shutter works fine, except that the 1 and 1/2
second speeds become
sticky and hesitant if not exercised regularly. Once a
week seems enough...
and, when they do hesitate, just tripping the shutter
several times before
using it cures it. I'm just wondering how severe one
should consider this
problem, and what can be done about it?

Pete

I answered this via Google groups last night but don't
see my answer in the thread so will repeat it. The Graphex
shutter is the same as the Wollensak Rapax shutter. These
are good shutters. The slow speeds are off because the
lubricant on the retarder escapment has become gummy. While
a good cleaning is the ideal way to deal with this a couple
of drops of Naptha on the gears of the retarder will
probably bring it back to life. Ronsonol ligher fluid is
pretty pure naphtha and easily available. To get at the
clockwork you must remove the front cover of the shutter.
This is done by unscrewing the front lens cell (I would also
take out the back cell). Under the cell is a chrome ring
which holds the front cover in place. Unscrew this. A grip
made of a latex rubber glove will help. The mechanism is
pretty obvious once the cover is off. Use a small brush to
apply the naptha so it goes where you want.
There are several shutter repair people who work on
Wollensak shutters. All of them use hair springs so its not
too difficult for a skilled person to make new springs when
necesasry. When the main drive spring becomes fatigued it
affects the higher speeds, not so much the low speeds, that
is almost always due to congealed lubricant. Excercizing it
will not cure it. Eventually it will stick. It really needs
to be cleaned. Modern lubricants are synthetics which don't
oxidize and gum, or at least not for many years.
If you _really_ want to get into this shutter you can get
a factory repair manual from John S. Craig at
http://www.craigcamera.com
The Rapax/Graphex was designed partially because the
Kodak Supermatic did not work well with flash synchronizing
solenoids. The Rapax/Graphex has a lighter "trigger pull" or
push, to trip it plus the force is constant with the shutter
speed. Also, the built-in sychronizer does not require
separate cocking as it does on the Supermatic. When tuned up
properly these are quite accurate and reliable shutters.
Unfortunately, some of the Wollensak lenses that come in
them are not wonderful.
Welcome to the Graphic club. They are hard to put down
once you get used to the thing.


--
---
Richard Knoppow
Los Angeles, CA, USA

In article ,
Richard Knoppow wrote:

I answered this via Google groups last night but don't
see my answer in the thread so will repeat it. The Graphex
shutter is the same as the Wollensak Rapax shutter. These
are good shutters. The slow speeds are off because the

Let me just reemphasize this -- these are *great* shutters. I have
owned two; both have proven more accurate *and* more consistent than any
other shutter I own, including modern Compur and Copal models.

They do stick if not used often, in my experience occasionally even when
kept reasonably clean. Firing the shutter 5 or 10 times in quick
succession after removing it from the bag at the beginning of a shoot is
a good precaution with these.

--
Thor Lancelot Simon
But as he knew no bad language, he had called him all the names of common
objects that he could think of, and had screamed: "You lamp! You towel! You
plate!" and so on. --Sigmund Freud

"Thor Lancelot Simon" wrote in message
...
In article ,
Richard Knoppow wrote:

I answered this via Google groups last night but don't
see my answer in the thread so will repeat it. The Graphex
shutter is the same as the Wollensak Rapax shutter. These
are good shutters. The slow speeds are off because the

Let me just reemphasize this -- these are *great* shutters. I have
owned two; both have proven more accurate *and* more consistent than any
other shutter I own, including modern Compur and Copal models.

They do stick if not used often, in my experience occasionally even when
kept reasonably clean. Firing the shutter 5 or 10 times in quick
succession after removing it from the bag at the beginning of a shoot is
a good precaution with these.

--
Thor Lancelot Simon


Echo the above, and you can repair them with "normal" tools. Try that on
your digital camera....

Truly, dr bob.