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13th December

At the last Ealing Fair, I bought a Kodascope L. Now, as you may recall, I don't much like Kodak machines, but this one was in lovely condition (with a nice box) and looked as though it had hardly been used. And indeed, it quite obviously not been used for a long time as the motor was seized up solid and the mech was pretty stiff and the belts were pretty trashed. That's caveated this emptor well and truly.  We live and re-learn. Now, a projector that ent bin used for possibly decades needs oil, and not just the occasional dribble as per handbook. In all that time, oil and bearings and felt pads and oiling systems will have dried out and need replenishing before any oil gets to where it is actually needed. But none of that worked and I had to face a fairly extensive dismantling to get to the seat of the trouble. Naturally, I thought of you lot out there and took some pix for you.

kdkl03a     kdkL04     kdkL05

Here are views of the machine with the major covers removed. Note the separate fan (the machine is designed for lamps up to 750w) and the fact that the motor speed control has to be unscrewed to get the back off. The claw mech (Pic3) seems very compact; there is a very small cam behind the front pivot.


In order to get at the motor, I had to unscrew the mains input plug, the motor and lamp switches and of course the securing bolts coming up from below. Then came the really nasty bit. On top of the motor sits a bracket with guide holes for the tubes of the oiling system. Four tubes come down from the main (felt-filled) reservoir above the top sprocket. They pass into the bracket then onwards into extension tubes with weird bends to the two motor bearings and the fan ditto. Not too hard to take apart but it's going to be a nightmare to put back - there is very restricted space in which to work.


kdkl06a     kdkL07     kdkl08a     kdkl11a

So here we see the motor successfully(?) removed along with the switches and mains socket. This, incidentally, is a right-angled jobbie, with two pins at the back for (presumably) mains input (110v as it's American) and a socket to the front. Better not get things the wrong way round and end up with two live pins. The motor, naturally, turns out to be one of those internal-brush types, shown in Pix 2 & 3. Not only is it impossible to change brushes without dismantling the motor, but the brush springs are loose and held in place by the respective wires, stiffened with solder, passing thru holes in the brush channels. I hate this system. Worst of all, you can only access the other end of the motor by removing the brushes,springs and wires, then the frame on which they are mounted so as finally to be able to release the through bolts holding the cap on. Guess which end the root of the trouble was?


I found that the bearing at this other end of the motor was seized almost solid onto the armature shaft. I knocked it out, thereby pushing the bearing out of its housing because it was so reluctant to leave the shaft.


kdkl09a     kdkl10a     kdkl11a

Pic 1 shows the result, Pic 2 what it should look like and Pic 3 the motor winding as stripped out. I managed to get the bearing back in, tho' it will never be quite the same, but first I had to sand down (fine wet and dry) both the shaft and the bore of the bearing to get a free-running fit. I had to do a bit of the same at the other end too. Then it was the laborious process of re-assembly. If you go back to Pic 3 of the second row of pix in this piece, you can see some brass spacers that support the brush frame. When I re-assembled, I had to replace these with slightly longer ones or else the brushes did not actually run on the commutator in a proper position. Who knows why?
All of this effort was, of course, with no knowledge of whether all this would work - I thought it more than likely that the motor winding had been cooked by successive efforts to make it run while it was jammed. So I decided to check it out before re-installing the motor. It actually ran, but lots of alarming smoke appeared. I kept stopping in case something really terrible was happening. By the time I took this photo, which anyway gives only a hint of what the smoke was actually like, it had reduced quite a bit.


kdkl12a

I can only guess what was happening; maybe the oil etc with which everything was liberally coated was burning off. However, when I looked closely the source seemed to be the commuttor, which had a twin ring of sparking round it. I wonder if I put one of the brushes back in the wrong way wound, so that it has to be burnt in again to the correct shape. Whatever, I am not impressed by the performance of the motor and doubt its ability to drive a very stiff mech. Only a qualified success, therefore, and I still have a hefty re-installation job to do. 

18th November


I have discovered the danger of playing with a Son ("). I hadn't finished messing with the first before I moved on to a second. This has now had the amp and tranny removed, a B&H DC Tachograph control motor mounted and a B&H diode fitted in place of the PEC. There is a lot more left to do, like a power supply for lamp, motor, amp and pre-amp and exciter, plus fitting the exciter (it was part of the amp wot I have removed) and finding stuff to do the electronic bits. I still do not know what voltage the motor runs on or how its speed is controlled. However, it fits quite neatly once the old tranny has gone and yes, the side will go back on round it. There is bags of room in the base to put the B&H tranny that I hope will provide most of the supply voltages I need.


Dismantling the projector showed what a dog's breakfast both motor and amp were. I will do you some pix.


Sonamp     Sonmotor     SonBHmotor

You will see I have severely truncated the support brackets for the B&H motor and fitted alu angle to provide a way to fix it down. If I ever do this again, I would be able to cut the brackets to a more precise length, and have them in contact with the base, rather than supported off the base by the alu brackets as here.This would avoid having to cut into the alu to match the curve of the housing for the rubber mounts at each end of the motor. I would probably have the front alu angle pointing backwards, so the flange is under the motor rather than in front. This would make it easier to fix to the plate with which I have filled the hole where the original motor was. The B&H motor shaft is 5mm, where the old motor shaft was a nominal 0.25" (about 6.3mm). I made a brass extension piece, the hole sized to be a fairly stiff push-on to the B&H shaft, with an external diameter to match the original fan and inching knob cum pulley.
Incidentally, I decided in the end that as far as the old Bolex described below was concerned, the game was not worth the candle so it has returned to its box.


9th November

If you want to know more about the early Bolex, you don't need to read the next bit, which repeats with much more detail and pix on the Bolex DA page. (There are actually 3 pages and you want P3, but because of software problems you have to go to P1, then link to P2 and follow on to P3).

 I mentioned at the end of my last posting that I had tried to start up an old Bolex Model C. I find I had opened up a bit of a can of worms. Next thing I did was to test the motor on its original machine, which I did by just attaching the wires, not by re-installing the motor. There is a good reason for this. The four wires from the motor, in their aged, oil-impregnated, highly inflexible sleeving have to pass thu a hole below the machine itself with a gap of less than half an inch between motor casing and projector base. The motor has to be installed slowly, pulling the wires thru a bit at a time, whilst balancing the need to fit the fan at the opposite end. The risk of permanently damaging the wires seems considerable.


I am sure I do not need to tell you that the motor worked fine; I should have carried out this test before I started. I now face the problem of tracking the fault thru the even older and more decrepit wiring of the old machine, or adopting a radical solution with a heart and lung transplant of the speed control resistance mat, the direction-changing switch and the associated wiring. I should mention here that one of the screws holding the resistance mat in the base of the old machine would not shift. In the end I had to drill it out and re-tap the hole, as the thread inevitably got damaged - I needed to do this anyway to check what lay beneath. 


This all seemed like a lot of work for a machine that would still look pretty rubbish at the end of it all, as age, rust and heat (in the case of the lamphouse) has made a real mess of thepaint finish even - and here is the main point - even if the finish was actually meant to look like scales on snake or lizard skin. The size of the "scales" varies so much I begin to wonder if in fact this was not some obscure fault of the paint shrinking, especially as I can see no real sign of any coating remaining between the scales. If the finish is original, is it worth the bother of making it work, if not, is it worth the bother of re-painting? The machine seems very early, with a few unique and interesting features. The lamphouse is many-sided rather than round, and there is a nickel-plated cover beneath the direction-change switch. But the original motor is kaput and the snake-finish cover of the original motor will not fit over the donor motor and anyway, much of the uniqueness lies in the paint finish. And it's a Model C - two gauges but no notching, just a still picture device and a centrifugal heat filter.


On a matter that will turn out to be related, I spent an enjoyable few hours one morning wandering about Leighton Buzzard and visiting various engineering establishments. I was well surprised at how many there were and the expensive automated machinery I saw - the town seems to have far more than its shareof engineering capability. What it doesn't have, however, is gear-cutting capability, which is what I was looking for. It appears that a) gear-cutting is a highly complex and specialised task, which requires special equipment if you're going to do much of it and b) in consequence of a), gear-cutting has become the province of a few specialist companies who can do it easier and cheaper and are thus used by most companies as a better option than maintaining their own capability in this area. What I was looking to do was to have some gears made to replace the paxolin gear in the post 1937 Bolex DA (I already had some done a few years ago for the pre-1937 model), that tends to strip its teeth after the first 75 years or so. We shall see if I can find another way.


6th November


I have had a rather dispiriting time of late. Part of it was understandable, as it involved working on a Son (Ugh!). This was a much-modified affair, with a new motor and a new solid-state amp. Sadly, these things did not come together in any very satisfactory way. The basic flaws of the Son ("), as we all know, were:-

1 A motor wound for 160v yet run on 240v (as well as having dodgy "rubber" mounts prone to failure). This was apparently in part at least so it would go fast enough from cold to approximate to sound speed;

2. The motor was a standard, rheostat-controlled variable-speed type, constant speed being achieved by means of governor contacts at the rear of the motor. This was not necessarily bad of itself, but together with 1 above,gave rise to a situation where, as the motor warmed up, it went faster and made the governor work harder unless the speed control was gradually reduced to match the increase in speed from the warming process. Burnt-out contacts were a frequent cause of return to the Pathescope workshops for repair.

3. The amplifier was poor, effectively just thrown together, down to a low price, 
by unskilled labour, in someone's garden shed  and very prone to fault.


4. The film path was very poor. A single, small sprocket is not ideal for a sound machine, especially when it required at least one very tight bend, nearly 180 degrees in half an inch, as the film met the sprocket for the second time.

5. Smoothing at the sound drum was poor.

6. I have heard reference to "Son-stroke" as a cause of film damage, in connection with the claw/gate combination, but I am not wholly convinced. The claw is in principle very similar to that in the Pax and the Elf and I am not clear why this would damage film - that tight bend in the film path is a much more likely cause. As for the gate well, it was cheaply made with poor aperture and masking but, again, no obvious opportunity for damage.


This particular machine has obviously had an adventurous life. It's a bit battered, with lots of paint chips, and some screw threads that no longer hold - inevitable when they are in a fairly soft casting. The lens mount has been enlarged to 1 inch (Specto or old B&H) and, as mentioned above, a new amp. The new motor installation is a bit of a bodge, with over-flexible mountings and imprecise location. Getting the right tension on the belt seems to drag the shaft across and put extra strain on the motor. A new circular rheostat (like in the Specto 500) seems to have some kind of associated circuitry that means it responds relatively slowly to changes in the speed setting. It is still, however, very much subject to speeding up as it warms up. Hammerite have a lot to answer for: a new side plate has been fitted to cover the amp and some benighted fool has manually applied Hammerite. This is NOT a good look and has been removed.

I have had a lot of trouble with the sound drum. The ball bearing race immediately behind was well past its sell by date and ran very rough. Unsurprising; it is unsealed and it seems in fact that it is impossible to find sealed ones as it just isn't thick enough, so my new one is unlikely to enjoy a long life. And lubrication is difficult because of acess problems. I also found that the re-routed supply to the lamp (I forgot to mention the lamp is now a 24v 250w halogen peanut. This is fed from an external transformer, the mains supply to which comes from the projector rather than having a separate mains connection), was rubbing on the flywheel and causing a surprising amount of friction. The perspex light tube from near the film to the photocell has been replaced by a rod in which is fixed some form of diode, but it looks to me to be at the wrong angle to catch enough of the light from the exciter (a 12v 20w halogen)(!) and will need re-doing. I have so far failed to get the flywheel running freeely enough, or the motor for that matter, and the only way I get decent-ish sound is by adding considerable pressure to the sound drum by hand; even then speed is very unstable and volume is low. And the lateral adjustment for the sound- reader is sloppy. Every time I need to tweak something, I have to do a fair bit of dismantling, and then re-assembling before I can test. I got bored with this and have put it on one side until stocks of patience are restored. I may have to go the whole hog and fit a B&H motor, as the current one does not seem man enough for the job.

Stocks of patience have not been restored, however, by a very old Bolex Model C. This has a weird, mottled finish and is basically much the same as a DA, but without the notching capability. I thought I should try to get it running. Hah! The motor was jammed, and only improved somewhat with lube. When I opened it up I found the cause - the motor has a Mazac frame and is cracking and distorting. This is pretty much incurable, and I am fairly confident the motor has burned out as a result of jamming anyway. I have a much later Model C, which I have been using as a spares machine, and the motor actually fits, but I cannot get the verdammten thing to give even so much as a twitch. Very frustrating. 

19th October

I took a stall at both Rickmansworth (now Chorleywood) and Harpenden. For some considerable time now, my cine life has been dominated by the need to get stuff ready to sell at these fairs; the fairs themselves are exhausting – all that stuff to haul in and out. It must be worse for those who are even older, more decrepit and more knackered than I am. Chorleywood was well enough attended, but I did most of my business at Harpenden, selling a Pax, a Home Talkie and a KOK. The KOK was the one I re-furbished recently, as chronicled in Reviving a KOK. I have more than enough parts left over to do the same again (but only a mains machine – no dynamo). I don’t want to do it, so I am offering a KOK “kit” to anyone ready to take on the job, at the bargain price of £50. All the really specialised parts are there – gate and lenses and the mech and various gears –tho’ you would have to make a lamphouse. Being a generous person, I undertook the tricky job of making a new condenser lens and projection lens just to leave the originals for this kit. Kind or what?

Because we have the idiocy of three fairs even closer together than usual this year, you need to be quick if you want to take delivery at Ealing. Is it really not possible for the fair organisers to space themselves out a bit better? From a punter’s point of view, it’s a feast followed by a prolonged famine. I shall be having a rest by going to Ealing just as a punter.

I did acquire one unusual thing at Harpenden, a junk Vox for spares. It does however have one or two unusual features that I thought might interest you. Here are some pix.

GreenVox1     GreenVox2     GreenVox4     GreenVox3     GreenVox5     GreenVox6

I like the neat idea of a sliding lampholder (pix 1 and 2), which may well be adaptable in the future, tho’ as you can see someone has dropped this poor machine on its head, causing cracks and no doubt completely wrecking the Bakelite parts of the lamphouse top. The mirror that reflected the light from the sound track to the PEC has been eliminated entirely, as well as the bracket it sat on. Instead, we have a two-part holder for a diode (pix 3-5). One part screws into the hole in the centre of the flywheel, with a small hole in the right place thru which the light passes to a diode in the second part. This relies on a complete re-vamping of the flywheel arrangement (seen from the back in pic 6) and, although it deals with any problem there might be of stray light getting to the diode, it seems a huge amount of work for a dubious gain. Fitting the diode directly in place of the mirror works very well and is a lot easier. Note also that the sound reader assembly and telescope appear completely new. I like the shield against stray light getting to the diode from the bottom of the lamphouse; normally this is inside, but having both might be a good idea. Given this shielding, it is hard to see why the re-vamp of the sound reading set-up was needed at all.

Some other work has been done, too. In pic 6, you can see that a roller race has been fitted in place of the simple brass bearing on the end of the claw shaft. There may be something behind the little cover seen just above it; not had time to investigate yet.

After all the careful work I have just described, it seems even more unfathomable that, for some bizarre reason, someone has considered that green hammered paint, applied thinly, badly and inconsistently, was somehow a good look! Still, I have a motor, various other useful spares and a couple of interesting ideas I can maybe build on.