[rollei_list] Re: OT: Question re shutter CLA and Ronsonol
- From: Jerry Lehrer <jerryleh@xxxxxxxxxxx>
- To: rollei_list@xxxxxxxxxxxxx
- Date: Wed, 12 Jan 2005 23:43:20 -0800
John,
The Castrol man was part right. Sperm whale oil WAS
used as a component in early automatic transmission fluids.
Better synthetic additives replaced it.
Jerry
John Jensen wrote:
> Many years agao (about 1963) I talked with a friend, a
> non-engineer, who took a job with Castrol in the San
> Francisco area. He was very enthusiatic about his
> job, his new company, etc. He jabbered about the high
> quality of Castrol, that it contained "whale sperm
> oil". After I picked myself off the floor, I
> explained to him that, if anything (I still had my
> doubts), it might contain 'sperm whale oil'. I left
> it at that.
>
> John
>
> --- Jerry Lehrer <jerryleh@xxxxxxxxxxx> wrote:
>
> > Richard,
> >
> > Very goooood!
> >
> > BTW, I still have a few cc's of sperm whale oil,
> > which
> > was supposed to be a non-oxidising oil to be used in
> > fine shutter mechanisms. Most oils will oxidise and
> > turn
> > into "varnish", which is the perpetrator of most
> > shutter
> > stoppages or slowdowns.
> >
> > There is an oil called Nyoil, made in the great
> > whaling
> > port of New Bedford, that used to be sperm whale
> > oil, then was JOJOBA oil, but I don't know what it
> > is
> > now. Non-oxidising oils can probably be synthesized
> > these days.
> >
> > Jerry
> >
> > Richard Knoppow wrote:
> >
> > > ----- Original Message -----
> > > From: "Ardeshir Mehta" <ardeshir@xxxxxxxxxxxx>
> > > To: <rollei_list@xxxxxxxxxxxxx>
> > > Sent: Wednesday, January 12, 2005 10:20 AM
> > > Subject: [rollei_list] Re: OT: Question re shutter
> > CLA and
> > > Ronsonol
> > >
> > > >
> > > > Still, at one time I did try to unscrew the
> > front elements
> > > > of the
> > > > Tessar lens to try and get to the shutter in
> > order to
> > > > clean it. I did
> > > > manage to unscrew the front element using a
> > rubber stopper
> > > > (I don't
> > > > have a lens wrench) but the shutter is
> > apparently behind
> > > > TWO lens
> > > > elements, and I couldn't unscrew the second
> > element. So I
> > > > just put the
> > > > front element back.
> > > >
> > > > I am wondering about the slot in the left bottom
> > side of
> > > > the lens, and
> > > > why this camera has it. Maybe you can enlighten
> > me. A
> > > > little lever
> > > > protrudes therefrom, which can also trip the
> > shutter. The
> > > > camera is an
> > > > early model Automat. Through this slot some bits
> > of the
> > > > shutter
> > > > mechanism are actually visible. I can squirt
> > vast amounts
> > > > of Ronsonol
> > > > into the shutter though this slot. I can also
> > drain
> > > > dissolved stuff
> > > > out, and at one time quite a bit of sludge came
> > out though
> > > > it after the
> > > > Ronsonol had loosened it up. Bits of black
> > solids also
> > > > came out -
> > > > specks of stuff like maybe tiny paint chips? I
> > thought I
> > > > was succeeding
> > > > in cleaning the shutter off completely, in fact
> > - so much
> > > > stuff came
> > > > out. But apparently I was wrong, for after the
> > Ronsonol
> > > > evaporates the
> > > > shutter still sticks, though not nearly as much
> > as it used
> > > > to.
> > > >
> > > > But the question remains in the back of my mind:
> > what
> > > > happens after the
> > > > CLA? Won't dust and dirt get into the shutter
> > again,
> > > > through this slot?
> > > > My 2.8D doesn't have such a slot, and its
> > shutter seems to
> > > > be totally
> > > > sealed against the elements. Why, then, does
> > this one have
> > > > such a slot,
> > > > though which dirt can get it? I am mystified.
> > > >
> > > > Cheers.
> > >
> > > You managed to get the front element off the
> > lens without
> > > removing the front cell. Its useful to be able to
> > do this
> > > because it allows cleaning the surfaces inside the
> > cell but
> > > it is not something that needs to be done more
> > than once in
> > > twenty years.
> > > Compur shutters are constructed so that the
> > mechanism is
> > > not exposed when the lens cells are removed. In
> > order to get
> > > to the works one must remove the front cell and
> > take off the
> > > front cover of the shutter. That allows removal of
> > the speed
> > > ring. Once that is off its possible to remove the
> > retarder
> > > mechanism. That is the worst offender in a shutter
> > which is
> > > behaving irregularly. The regulator is a
> > clock-work
> > > mechanism. Its cleaned by soaking it in Naptha
> > followed by
> > > pure alcohol. Once cleaned its lubricated by
> > putting the
> > > tiniest amount of fine oil on the trunions of the
> > gears and,
> > > perhaps, a touch on the pallet. Suitable oil is
> > available as
> > > Nyoil and the finest grade of Lebell silicon oil,
> > available
> > > at hobby shops. The retarder is replaced and its
> > position
> > > shifted until 1/10th second is exactly correct.
> > The other
> > > speeds should then be accurate.
> > > Further cleaning really requires removal of the
> > entire
> > > shutter from the camera and its disassembly. Its
> > important
> > > to have a drawing of the thing so you can see how
> > to get it
> > > back together. The shutter and diaphragm blades
> > are cleaned
> > > in solvent and the shutter blades polished to
> > remove any
> > > trace of residue. The shutter is then
> > re-assembled. Some
> > > Compur instructions indicate that a trace of light
> > grease
> > > should be used in a couple of places but I was
> > told by a
> > > fellow at Compur several years ago to just leave
> > it dry.
> > > The top speed of Compur and most other shutters
> > is the
> > > _effective_ speed for the full shutter aperture.
> > Since the
> > > shutter has a finite opening and closing time this
> > is rather
> > > faster than the total open time as measured for a
> > small stop
> > > or by a small sensor at the center of the
> > aperture. For
> > > Compur-Rapid and Synchro-Compur shutters the
> > marked top
> > > speed is about 80% of the total opentime. i.e.,
> > for a
> > > shutter marked 1/500th second the measured top
> > speed is only
> > > about 1/400th. I think Compur specifies somthing
> > like
> > > 1/380th as the limit. Compurs should be within
> > about +/- 5%
> > > for speeds to the top speed but that one can vary
> > as much as
> > > 20% from the nominal speed.
> > > The use of effective speed markings is also
> > found in
> > > focal plane shutters, particularly Speed Graphic
> > and Graflex
> > > cameras because the shutters in them are not very
> > efficient.
> > > It is possible to measure the _effective_ speed
> > of either
> > > a leaf or FP shutter using the little Calumet
> > tester but it
> > > requires careful set up so that the light
> > intensity at the
> > > half open and half closed points fall at the
> > threashold of
> > > the sensor.
> > >
> > > ---
> > > Richard Knoppow
> >
> === message truncated ===
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