Heurtier Silent


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(Heurtier Sound)


Heurtier Supertri Silent


Heurtier also produced a silent triple gauge machine. For some reason, one finish they used (as did Bolex) was sort of drab, olive-green and slightly wrinkled. I think it's nasty and it's a bugger to keep anything like clean. I much prefer the hammered finish shown here.

One of the first things I do with any new projector acquisition is to ensure that it's earthed. This machine, however, posed a problem. Fitting an earth lead seemed to short out the motor resistance, so that the motor raced away at full speed. This implies the case is live. However, the resistance itself was breaking up, so I fitted an electronic thingy instead, which solved the problem. I have, of course, kept the resistance, so that the machine can still be restored to original specification. I cannot emphasise enough the importance of this; don't make permanent changes, and always keep the bits you take off.

I acquired another silent (olive green) one cheap, as it kept losing the loop and this offered the opportunity for much tinkering. The natural inclination was to blame it on the claw, which had lost one of its three pins. This was corrected by a friend of a friend by brazing a new pin in place - once I had actually got the claw out. I have rarely had a tougher battle to get inside a projector and strip it down. The mech is the almost circular construction in the picture, with the gate, claw, lens housing, gauge-change knob and two triple sprockets as a unit that can be removed as one piece.

At the back, on the same shaft as the sprockets, are two pulleys. These have to be removed, but there are no visible screws - they are hidden behind blanking plates held into a recess in the face of the pulley by a large spring clip, in the form of a nearly complete circle. One of the underlying screws has a left hand thread, to catch the unwary. They were of course seized solid, and I got them out only after a prolonged fight. Only then can the back cover be removed. There was an interesting ratchet , with a three-cornered cam, rather like a Wankel engine rotor, held in place by the screw. Small steel balls in each of the three "pockets" round the cam lock against the sides of the recess in the pulley in one direction, and freewheel in the other, and are held in place by the blanking plates.


Here the mech has been removed. In the back view of the mech, the vacant hole in the bearing is where the main claw shaft was, after being bashed out with some force.




These are front and back views of the lens/claw assembly. The shaft carrying the cams for the claw and cam change mechanism has been removed, but the claw itself can be clearly be seen. This assembly is fixed to the main mech by two screws hidden deep in the compartment with the springs. The wheel at the bottom is for framing. On the far left of the left-hand picture is a small brass bush. It holds a small steel ball, behind which fits a spring. The ball fits the grooves on the lens, providing for focussing. There should be a second one just below it - I had to make a new one. When I finally re-assembled the machine, I left these out and had to largely dismantle all over again.


heurtier-silent Left is a view down into the mech. The shutter assembly, right, had to be removed before the mech would come out of the main body of the projector.


I felt pretty pleased with myself for managing such a complicated job, but I was quite surprised that the projector still ran. But it also continued to lose the bottom loop - the claw was not the problem. To cut a long story short, I ended up gluing two thin strips of brass to the edges of the gate so as to move it towards the claw. This seems to work fine, but it is galling that I cannot see how the problem arose in the first place The relationship between the claw and the gate is integral and it simply should not be possible for it to change. (Look at the heurtier-silentclaw/lens assembly above, front view). The spring top left holds the gate shut; the back of the gate slides into a slot running vertically behind where the spring is. See new hastily-taken pic left. I have left the gate half out and open. One of the brass strips is visible; it has the effect of pushing the gate to the right, towards the claw.




I had another Heurtier Super-Tri silent projector in pieces (mid 2011). It had been been awaiting attention

for several years, having more or less completely seized up. It's a bugger to take apart - it seems to have been

made deliberately difficult - and at the moment I'm not at all sure I can manage to get it back together. I got

around to it because of some questions from another collector, who had bought a Heurtier Universal that, despite

good packaging, had been damaged. Part of the damage was to a double gear that drives the tripe sprockets, and it

was not at all clear how the thing was supposed to be. In fact, what we have is two thin gears (about 1/16th thick

each), possibly cut together as a single piece. These are at the end of a shaft, with no obvious indication as to

how they are held in place. My contact's gears were loose on the shaft, I had to do some dismantling to be quite

sure they were supposed to be fixed, so I thought I might as well sort the Super-Tri out and kill two birds with

one stone. It looks to me a poor piece of engineering - the gears seem to be fixed by a combination of heat-shrinking

and peening, by which I mean in this case that a pointy thing seems to have been bashed into the join between shaft

and gears to force them into each other a bit. I don't like it - seems too fragile for such a vital part. It's no doubt

due to the size restrictions imposed by the design of the triple-sprocket assembly. Again, I shall do you some pix.


Closer examination suggests the fixing of the gears is less flimsy than I first thought. There

may be a "keyway", ie a slot in both gear and shaft into which a small piece of metal fits, providing positive

engagement. It must be pretty tiny, mind. Having got it the rest of the way apart, it seems obvious what the

principal cause of seizing up must have been.


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Pic 3 shows there are two big fat felt discs around the claw/cam area. They were bone dry and absorbed a lot of oil,

without starting to leak it out again. This seems to be an increasingly common syndrome. An old projector, maybe

unused for years, is pressed back into service and one hesitates to put too much oil in, remembering all those

injunctions in instruction books not to over-oil. So it never gets enuff oil to re-charge felt reservoirs or penetrate

fully to all the surfaces needing oil, which are anyway covered with a layer of old, dried-up gunk which has become

sticky and is certainly not doing the lubricating job it was originally applied to do. It may well be that a major

overhaul every 40 to 50 years is sensible. Another thing I found with this particular machine was that the mech as seen

in pic 4 was stiff. I wondered whether maybe fibre gears tend to grow very slightly over time, eg due to absorbing oil.

You can see in pic 4 two big screws on the side of the black plastic mount for the shutter shaft. These enable

adjustment of the meshing of the shutter shaft gear with the mech, which helped a bit. There is a further screw

on the top of the same mount, which seems to have a spring under it. Easing this a little helped even more, tho'

to be honest I'm not exactly sure what it does.


I have had to go further into the Heurtier; here are the pix.


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My problem was that the claw seemed to be bent out of its correct flat shape and it had to come out for

straightening. You can see the framing mech in the first two pix; it's a ring that goes round the main claw shaft and

cam. It seems to be connected to the body only by that spring; you can see in pic two the long pivot on which

the back of the claw travels horizontally to change gauge and is moved vertically for framing by that thin serrated-

edged wheel on the outside. Note in pic 3 the different thicknesses of the claw pins; I gather it is fairly normal for

only one pin on any claw to do most of the work, with others as back-up.


Pix 4 & 5 show how the claw rides in its carrier. The exploded view in the final pic should help show how it all fits

together. Note in pic 4 the three pins on the circumference of the narrower part of the carrier. These engage with

a set of spiral grooves inside the black plastic gauge-change knob. The spring is placed between the narrower part of the

carrier and the knob. You have to push the carrier against the spring until the pins and grooves engage in order to

re-assemble. Needless to say, there are two wrong positions at which these can engage and only one right. The felt

pads, suitably soaked in oil, surround the claw and cam. You can see how it all slots together in some of the earlier pix.


The cam is made of some sort of fibre/composition material, not metal. But now look closely at the claw shuttle in

pic 3; the internal shape seems weird in the extreme and, if the cam was not fibre, you would swear it was wear.

But how could a fibre cam do that? Note that the exact position of the cam on the shaft is obviously critical, so

that when you pass the cam on its shaft thru the claw shuttle, into the bearing that is in the gauge-change knob,

it ends up in exactly the correct position for each gauge. I have had to do it by trial and error; presumably they

had a better way. There seems, incidentally, to be no way at all to remove the pulleys from the shaft, which

would have made the whole business a lot easier.


The last piece on the right of the exploded pic is a sort of inching knob, which also is part of the mech that locks

the knob in place for any particular gauge.



I am coming to the conclusion that the claw gets bent out of shape either in the

initial re-installing of the total assembly or, more likely, when trying to change gauge with the cam and claw not in

the correct alignment. The claw appears to be spring-loaded; it needs moving about before it will slide over the cam

when re-mounting the assembly. Although it can't really be seen in the pic (6 below), the triple cam has one area

where all 3 cams segments for the three gauges are at the same level, ie there is a common "flat" (in fact, rounded)

area. I am theorising that if everything is correctly aligned, when changing gauge the claw slides across the "flat"

area and so does not get bent.



Let me try to explain with this pic. The gauge change knob - the serrated black plastic thingy - has

slots or grooves for each gauge. Above the black knob is a spring-loaded silver knob, with a rod that

fits into these grooves, so providing positive engagement. There are also "stops" at each end of the

black knob's travel to prevent it being turned too far and causing damage. The silver knob can only

be pulled out to allow the knob to be turned to change gauge when a slot in the inching knob - in

the centre of the gauge-change knob - is next to the spring-loaded rod to enable the rod to be pulled

out. Otherwise, the inching knob fits tight up against the rod to prevent it being moved. The inching knob is held

onto the main drive shaft carrying the cam by a grub screw which tightens against a flat on the shaft, so it can only

go on in one place/position. The cam has no pre-fixed position and is simply held in place (when you find the place)

by a pair of grub screws. So my guess is that one must position the cam so that, when the inching knob is aligned to

allow the spring-loaded knob to be pulled out, the "flat" is correctly positioned. Since the claw is spring-loaded, but

not necessarily in a straight up, down, in or out position (because there are 2 springs) I now have to figure out

what the correct cam position is.


I think I have already got the in and out location of the cam, ie 32.25mm from the end of the shaft to the bush. I

have had problems with getting the gate to go in; this seems to be because the claw gets easily bent out of shape

and is then angled slightly out of line and so fouls the security device which ensures you can only insert the correct

gate for the gauge that has been selected (you have to remove any gate before you can change gear).

Much of this will of course be clear already to anyone who has operated a Heurtier, but I hoe that info on the way

the cam and claw inter-relate may be useful if you ever have to dismantle one. Wouldn't it be nice if we had service

manuals instead of having to try to figure it all out oneself?




Heurtier PS8


I have before me 2 rather different Heurtier PS8 machines.

On these, the front opens with a simple catch, then hinges up to sit on top of the main body.

The arms slide forward in slots to align with the film path. All this time, the spring belts remain

in place, so there is much twanging and boinging. When the machine is closed, the belts lie along

the top of the unit, with plastic sprung covers over them. Another odd feature us that the back

of the projector has a circular disc set into it. This is spring-loaded; a press and turn makes it pop

out by about 2cm, revealing a 360 degree circular slot thru which the power cable is wound onto

a core. The circular thingy doesn't move; you wind the cable on by hand. Both machines had

bare wires when received, but there is no way you can close the thing up again with the wire

still poking out. There has to be, therefore, a plug (2-pin only, incidentally) that will fit into

the narrow slot available, which is only about 1 cm or so. I managed to find just one plug that could

be pushed in, and I have plenty to try. Thin plugs would be gratefully received. NB that blank circle

inside the raised lid should contain the operating instructions, shown separately below.


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The differences start with the colour scheme. One, which I assume to be the earlier, is in pale

blue/grey enamel, the other a scruffy silver Hammerite-type hammered finish. I assume the blue

one is earlier because it has a lamp I have never met before, 10v 100w, standard small incandescent

in appearance, but with a mini-reflector behind the filament. The base is 3-pin twist-and-lock like

some exciter lamps and like lamp in the other machine, which is a standard 8v 50w Mae West.

The blue machine seems to have had some mods. It has a 2-pin outlet (original) on the back,

labelled Sync (although someone has disconnected the two wires), and there appears to be

provision for a mechanical link from the rear of the projector main shaft. Less standard are

the addition of a Dim-Off-Bright toggle switch for the lamp, below and in front of the lens. Another,

slider, switch has been added in front of the reverse/forward slider switch. The function of this is

unclear to me since all it seems to provide is an additional on-off for the motor.


The shape of the machine from the operating slide is a bit like the Eumig P8, (irritatingly, the

lens barrel is just 1mm greater in diameter then the P8) and also a bit like a shoe. It has an unusual

drive which is semi-exposed at the rear of the machine. It was not keen on a tight belt; I found a

very flexible one which it liked much better. The machines are amazingly compact when folded,

just 9" x 9" x 6", with no odd bits or arms sticking out. I begin to think that the last days of Std 8

silent saw some of the best projectors.




Home ContentsProj. Index 9.5 16 Multi-gauge 17.5 28 Pix Miscellany