Home 9.5 16 Multi-gauge 17.5 28 Pix Miscellany
PATHÉ REX/RURAL 17.5
Pathé brought 17.5mm to the market in 1926 or even 1927, a full three years or more after Kodak introduced 16mm. It was almost certainly this delay that meant 17.5, a gauge obviously technically superior to 16, eventually lost out. Their first machine was the Rural, glimpsed occasionally in adverts in the UK as the Rex. They are very rare, I suspect because most of them were converted to sound - see Rural Sonore. I found one at the Argenteuil film fair near Paris in 2008.
I have just spent a lot of time fettling the Rex up for use, as
I do have some silent film and have recently acquired some more. The problems I
encountered are typical of those that beset the restorer of machines that are
ever older; it is perfectly possible that this machine has run little or no film
since before WWII. This has not stopped it fighting me every inch of the way.
This is the machine from the angle usually shown in publicity.
The first problem was that it had no lamp transformer, having
obviously been cannibalised at some point. However, I had already established
that the Rex and the later sound version used a lamp with the same fitting as
the Vox and, I am guessing, actually used the same or similar lamp and tranny. I
had a loose Vox tranny which I decided to fit. As ever, the problem is
trying
to fit something without altering the projector, which you will know is anathema
to me in most instances. There were only two mounting holes available,
positioned centrally; the Vox tranny had one per corner, all therefore in the
wrong place. I took a 1cm square iron bar and drilled a central hole for a bolt
to fit one of the available holes in the projector. Threaded holes at the ends
of this bar provided mounting
holes for one side of the Vox tranny. Obviously, with just a single point
fixing, the tranny wobbled, so I made up a long rod to provide support from the
other original mounting hole. A flat plate covers the gap from this rod to the
two remaining holes in the Vox tranny. This plate also gives a convenient mount
for a terminal strip. It's probably all a lot clearer from the pic; you can just
see one end of the 1cm square bar at the side of the tranny above the green
earth wire (I try not to operate without an earth having a strange desire to go
on living.).
This
leads me on to the next point. The machine as designed has a single switch to
operate both motor and lamp, which I don't like. To fit a separate lamp switch
without altering the machine was a simple matter of extending the two bolts at
the bottom of the switch panel to provide fixings for a plate on which I could
mount a switch (and earth connection), with just enough clearance to fit below
the projector base. This is the view from the outside; you can see the rest in
the pic above. You can clearly see the bolts and nuts and the spacers to give
clearance for the switch in the top pic. (I have since covered all the switch
terminals with heat-shrink insulation to obviate any risk of shock). All
terribly simple. Except....... The two bolts screw into threaded holes in the
projector base, but I could not find any bolts in my stock to fit. This, I
discovered, was because although the bolts were a standard M3 size, they were
not the standard 0.5 pitch, but instead 0.6. So I had to send off for a die, and
a tap (because I would need to make the nuts as well). Even then, the first die
for some reason gave off-size results and I had to ask for a new one.
Anyway,
in the end it got done. here is a close up of the switch panel, with resistances
for both motor and lamp. The ammeter (the two terminals at the very top of the
first pic above) is scaled to show a red line at 2 amps for the lamp. 200 watts
at 110v - sounds about right, if a bit low. The problem is, with no tranny I had
little idea of what the wiring should be. It looked a bit as if both the
transformer and the lamp were wired as one circuit. Anyway, I had to
change things for the separate lamp switch. I originally planned to eliminate
the lamp resistance, but in the end kept it. I tested the motor direct from
110v, and it was fine. Wire it into the circuit and zilch. In the end I found
the motor resistance mat had a tiny spot where there was rust, and the wires had
simply ceased to be for a few thousandths of an inch. Fortunately, this was very
near one end, and I only had to remove about 2 turns to get a new end.
The lamp
shows well under two amps on the meter even with the resistance turned up as
high as it will go (Mind you, the ammeter may not be very accurate - it had a
small pool of dried-up oil in the bottom of the dial). The tranny reads about
14.7 volts with no load. Have not yet measured under load. There are two
inputs to the tranny, for 110v and 130v; the second gives about 18v. I have
tested with a Vox lamp and (because Vox lamps are hard to come by) a 15v 150w
halogen. More on this later. These two pix, incidentally, show the machine sans
lamphouse.
The machine came with spool arms which take only 500' spools.
Fortunately, I had some ready-made "Super Arms" i
n
the shape of the arms from one of my sound Rurals. Yet another snag here - the
brake mechanism for the feed spool was busted - Mazac had distorted and enlarged
and was solid. I had to mill it out in the end. Then, of course, I had to
make a new part to replace the Mazac one. The bright aluminium is the new part.
The two black sectors are brake shoes, pushed against the rim by springs running
thru the alu bit. The centre screw is the end of the spool spindle, and takes a
dished spring washer and nut to complete the assembly.
Having cleaned and oiled and generally checked all was well, I
finally felt in a position to run some film, so got out the first two reels (of
8!) of my tinted copy of Christus - yes, the one that's on 9.5, but even longer.
I got about two thirds of the way thru. I noted along the way that the framing
was off - and there's no adjustment on these machines. Nor is there
enough
slack in the screws that secure the gate to make any significant difference. At
this point we may as well look at the lamphouse and gate. I had been concerned
at the small size of the lamphouse given the amount of heat an incandescent lamp
would generate. However, there seems to be a pretty good draught thru to the
lamphouse and, when running, the machine makes quite a howl. An interesting feature is that some of the stream of air is diverted
to the gate, which even has little "wings" to channel the air. You can see in
the first pic, at the bottom, where the air goes to the main lamphouse. Do you
by any chance recognise the lamphouse locking mechanism in pic 2? The machine
was built by the same concern as the Pathé Baby and also has a cam which is just
a scaled-up version of the one in the Baby.
To try to get just a little bit of adjustment for the gate plate to deal with the framing problem, I have made replacement securing screws with the head and the shank reduced from the original. However, I can't yet see if this works, as I shall explain.
I
said I got about two thirds of the way thru my reel of Christus. Then I lost the bottom loop, the
cause being the claw failing to go back in after the downstroke, and simply
moving the film back up again. Here are some shots of the claw mechanism pre
failure; you
can see the giant Baby cam behind the up/down cam. You can also see the two claw
pins and, at the back of the brass claw carrier, a little sticky-out bit which
actually goes over the giant Baby cam. There is another bit you can't see which
sits on the near side of the same cam, and these two together provide the in and out claw
movement. Here is the actual claw bit removed from the carrier; you may be able
to see that one of the two sticky-out bits has fallen off. To me, it also looks
like it's
failed
before, as there are signs of a brazed repair. This is not something I think I
can fix myself so, for the time being, I'm stalled. I have made a drawing of the
claw shuttle, with a view to trying to get one made - I think it is some special
or toughened steel.
In fact, I ended up making one myself. It's not quite right, but I know what is needed now and when I can summon up the energy I can hopefully make a really good one. The main problem is that in trying to get it to run freely, I took a bit too much off the sides, so it has too much lateral movement and enters the film at an angle. My new one is finally OK, and I have made an attempt at case-hardening it to help limit wear.
A peculiarity of this machine that I have not previously
encountered on 17.5 is that there is a moving plate inside the
lamphouse,
which either cuts off the light altogether or acts a a heat shield for a still
picture - I think. The lever on the front has two clear indented "stops" which
as far as I can tell correspond to the two possible positions of the plate noted
above. It links to the spring-loaded plate in the lamphouse by a wire in a cable
like for bicycle brakes. The lamphouse end was adrift and I had to find a
good way to re-attach it. It all looks a fairly professional job, so may be
original. There is no
provision for stopping the projector mech, tho', so I assume the function was to
enable the machine to be started with the light blanked until the leader was
thru and the film proper began. I overcame this same problem by adding a
separate lamp switch.
I have f
or
a long time wanted to make a tungsten halogen lamp converter for the Vox that
does not involve changing the projector in any way. Past conversions I have done
or seen mount the lamp in the side of the inner lamphouse, burning sideways. I
reckon if a halogen lamp can burn sideways, it might just as well burn upside
down. This is bound to shorten its life, but the lamps are a bit more readily
available than Vox lamps. I have tried in the past to make up a ring with pins
like the Vox lamp pins, but have always found this too tricky for my
capabilities. I have therefore adopted a slightly modified approach as shown in
the pic. An aluminium disc about 41mm diameter and 2 or 3mm thick sits neatly
just above where the Vox lamp would sit, where there is a convenient (insulated)
"step" in the lamphouse. The lamp is suspended from this by two
support bolts. These in
turn attach to a separate little unit made up from a washer drilled for the
lampholder and the support bolts, with spacers to get the lamp down as far as is
needed. There is fine adjustment of the lamp position heightwise by moving the
nuts on the support bolts (either side of the washer) up or down. Electrical
connection is made first by a bit of bent brass strip screwed to the alu disc
and bent down thru a slot in the side of the disc. This sits into one of the
holes the Vox lamp pins use and tits fixing bolt also secures the first lamp lead. The second
connection is thru the insulated rod, which is threaded at one end and so bolted
to the alu disc. The other end is drilled for a short brass rod, with a threaded
hole part way down matching a hole on the side of the insulated rod. A screw
connection can then be made to the second lamp lead. The brass rod protrudes
thru the top of the insulated rod to connect to the contact in the lamp cap.
It all sounds OK, but this job nearly drove me crazy. The main reason is that whatever idiots designed the lamp base set the lamp pin sockets at a weird angle to the holes I use for screw mounting - you can see this in the separate lamp base I have put in the picture above. My first approach was to use brass rods with a screw thread at each end, directly bolted to the lamp base. This ought to work, but..... The filament in the Vox lamp is suspended from two rods which are bent to move the filament closer to the condenser lens. I found I couldn't get away with straight rods moved further across as they then fouled the bore of the top section of the lamphouse and also the heat shutter mechanism. So I tried using bent rods. However, because the fixing holes and the lamp pin sockets are at that weird angle, one rod has to behind the other where they attach to the disc in order to get the filament square to the condenser. This seems to mean that the rods cannot be identical, 'cos I tried and failed. I could not figure out how to make the second rod the right size. In the end, I came up with the design I have described, which seems to overcome most of the problems, but it took me a lot of trial and far more error to find exactly where the holes for the support rods needed to be in the alu disc. I was homicidal by the time I finished, but at least I now have something I can simply copy.
It took hours and innumerable dismantlings and re-assemblings of the claw and gate to get it right. The in-out movement of the claw is very short, so the pins have to be exactly the right length to pull the film down but retract out of the way on the upstroke. This was all complicated by the gate binding and failing to provide enough pressure to hold the film. I was trying all sorts of things, including putting a shim behind the front, fixed gate, which in turn affected the length the claw pins needed to be. The gate binding was a real nightmare. The gate is pretty much completely enclosed in a channel, so you can't see exactly where it is binding. I filed a bit here, polished a bit there, experimented with various thicknesses of spacing washers on the lamphouse pivot; each time I tried anything, it was take apart then put back together over and over again. What I had thought would be a reasonable job took many hours of work over several weeks.
It will run film now; the framing problem is almost fixed but is still just visible on titles and some shots, so sooner or later (probably later!) I shall have to try something else, even if only to appease my own perfectionism. There is also occasional framing problem on the left of the screen - I think the silent aperture plate was cut a bit too big. I am currently trying a secondary mask behind the fixed aperture plate
Another little problem was that the top sprocket retaining roller was not quite right and led to the top loop shortening. The locating pin did not quite fit in its hole and there was no spring to help hold the roller in place. I enlarged the hole a bit and fitted a spring. Finally, I spotted a small hole in the bottom of the lamphouse, for which I could see no use. However, on projection you get a shaft of light onto the ammeter!
Here it is from a more normal angle.
These are the original 500' capacity arms.
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