Vincent's Film Slitters
Pictures presented in stereo are
parallel eye viewing.
This slitter allows the slitting of 35mm film into two rows of
9.3mm wide film for minox cameras.
(actually, the two rows produce four to six rolls of film)
This design is similar to the many designs on the web that use
razor and like blades.
However, by slitting in a light tight box, the film can be slit
in daylight. The film is then rewound into the
the 35mm cassette for latter loading into Minox
I used a plastic camera
I pick-up at a garage sale for $5 as the base for the
This provides a cheap
light tight box as well as the film transport mechanism.
Front view of the camera. Notice the beefy film wind
I added. (aluminum
with African Rosewood knob) Slitting film requires alot
Side view of the slitter. I built a wooden box to enclose
the knife blades from
light leaks into the film chamber. (oak actually, sealed
to the camera
with lots of RTV silicone) The knob at the back allows
knives to move back and
forth into (or out) of the film plane.
Here's an assembly view. The blades are mounted on a pair
of UHMW plastic blocks,
which can slide back and forth on pins.
Four brass pins are screwed into two aluminum blocks glued onto
the back of
the camera. These four pins fit into four holes in the
Three craft (or safety) blades are used to cut the film.
These blades are much
stiffer than standard razor blades, and thus can permit closer
Two UHMW polyethelyne blocks provide the proper spacing and
sliding of the blocks on the pins.
Here's the rear door of the knife box with the draw bolt
The draw bolt
is used to move the blades back and forth into the film.
felt along the lip to light seal the box.
There are a few modifications to the camera. A large
hole was cut into the
rear door of the camera to allow the blades to pass
A stronger crank
and shaft (shiny brass) can be seen passing through the film
reel. As well,
a piece of matte board has been placed in the lens
The tips of the
blades press into the board, keeping them from wavering.
It also prevents the
film from being pushed into the lens cavity.
Here's the original film pressure plate. Because its
I easily machined
three slots for the blades to pass through. The pressure
plate ensure that the
film is flat while being slit.
My first design actually had the blade block bolted directly
the back of the camera.
However, as the film is drawn backwards into the 35mm film
after slitting, the back of
the blades would still cut, leaving shavings in the
Thus I devised the draw bolt to move
the blades in and out of the film plane.
Punching the "Keyhole"
Some people have asked how I punch the "keyhole" shape onto the
end of a minox film roll so that it may be attached to a minox
reel. I use two different punches, in a wood base to stamp a
shape onto the film. Slots in the wood make sure that I punch the
holes in the correct location.
Here's a close up of the resulting film.
The figure 8 allows the film to be "locked" onto the peg at the
bottom of a minox film tank.
Here's a "contact" sheet of a strip of negs. (I acutally
project the negs.)
Notice how close the image comes to the edge of the film.
A stereo picture using the minox with the cha-cha method.
127 Film Slitter
This slitter cuts down a roll of 120 film for use in cameras
the old 127 film size.
I can actually get 12 shots instead of the usual 10, if the
has enough space to fit
the resulting fatter roll.
I used an old Kodak Bownie camera. It's really designed
620 film, but with a few
modifications, you can fit a 120 film roll into it. (I
still use it as a camera
if I take out the blades.)
Here's a rear view. Notice the matte board pads that the
knives press into. These
pads are light sealed onto the camera with big gobs of RTV
Two razor blades are bolted to an aluminum block, machined to
width. The block itself is the bolted onto a cross
which is bolted
to the side of the camera. (the two shiny bolt heads
Two square holes cut into the back, for pads which are used to
hold the knives
steady. (I used regular razor blades, which can wiggle
to side while cutting
if not held)
Notice the brass pins that I installed in place of the small
ones. Due to the
larger hole in the middle of a 120 roll, the smaller 620 pins
The 127 film width is actually narrower than the paper
However, as the film must
eventually fit into my developing tank reel, I cut both the
and paper, at the same time, to
the film width (about 1.8"). This results in the film
being shorther than the film reel,
allowing fogging along the edges. A little care in
and keeping the film in the dark until use
helps to minimise the amount of fogging.
Here is the resulting 127 negative, taken with a Coronet Stereo
(f11, meniscus lenses)
Close-up of the light leak along the edges.
As the film is cut along both sides, the numbers still appear
of the paper backing. Thus the little red window can
be used to
help advance the film.
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