WHAT'S NEW PAGE 9

 

 

1st October

The reason there has been little to report is a couple of weeks of holiday were followed by a month of chaos while the kitchen was re-done. And there are cine Fairs to prepare for.

27th August

I thought I should update you on progress following the Great Software Disaster of 2015.

It has all turned out to be a much bigger task than even at my most pessimistic I had expected. The reason is that, basically, only a tiny proportion of pictures have survived the transition from Front Page to Joomla! as the operating system. As Cinerdistan (pl bear in mind there is now only .com) is primarily about pictures, with up to 100 on some pages, this is a big job, but it is rendered much tougher by the disadvantages of Joomla! compared with what I was used to with Front Page - I don't think any modern software really envisages a site like Cinerdistan. Quite apart from having to track down the originals of all the pix, I now have to worry about picture size, having been advised I should not normally exceed about 400kb, whereas many of my pix have been over 1mb, some over 2mb. This means every picture must be copied to a new file and checked for size. Oversize ones have to be ruthlessly cropped, or have their background change or simply be reduced in  byte size via photo editing software. On the" in for a penny, in for a pound" principle, I have also been taking the opportunity to improve pix that are too dark or otherwise less good than they might be. Then the pix have to be uploaded (everything in Joomla! takes place on the mainframe, not ones home computer). This can be done in small batches, but actual insertion into the text has to be done one pic at a time and, and here's the rub, the insertion window has to be opened afresh for each pic. Especially if broadband is running slow, this can be excruciating. In Front Page I could upload batches of whatever size all at once. Another drawback is that, since the live bit is not on my computer, I can only have one window into the system open at a time (so far as I understand, anyway). If I am making changes that affect a group of pages, opening and closing pages repeatedly, with the usual delays, is a pain. And I am continually toggling between the old website (which IS on my computer), the Joomla! edit page, and the public page because I cannot view from the edit page anything I have done there; I have to wait while it gets saved and then check it on the public site.

Anyway, enough of me moaning. I just wanted to assure you I was trying to get back on track, without letting the website completely take over my life. Bear in mind that the text and most links have survived pretty well; if there is anything you particularly need to look at, it's not too hard for me to update a pic or two on request. I don't think the picture quality has been reduced noticeably, but I still have the originals anyway.

20th August

I have been doing some finishing-off work with my 9.5/16 Ditmar Duo. You may recall that a long time ago I showed pix of some extension arms I had made to allo the use of 900' spools, but I have never actually gotten round to mounting them. I was a bit concerned at the time about how sturdy the joins were; certainly for the bottom arm, these concerns have been borne out. This arm needs to be quite long, to keep a big spool out of the way of the base of the projector and below the pathe of the light from the lens. It also gets a strong pull from the take-up belt, and the way the arms are mounted leaves only a very smalll area to bear all the load of holding the thing in place. I have done a couple of pix, which I shall put in the Ditmar section - there is a link in the 18th August entry below.
My other project has been to fit a separate lamp switch at the front of the machine. At the back, there is a triangular paxolin thing with 2 (in some cases three) connections and a switch below. Shorting the two connections, or the top two of the three, allows the lamp to work. My 8/9.5 machine has 3 connections and the switch serves also to turn the lamp on and off. This seems a pretty useless facility as it duplicates the effect of simply removing the shorting plug and is, being at the back, in completely the wrong place and very difficult to operate. The 9.5/16 one has had the switch set up to give dim/bright switching for the lamp, but one is still left without any sensible way of turning the lamp on and off. I have sorted this by mounting a switch in a box under the base - the pix make this clear.


18th August

I have been making a concerted effort to get some long-stalled jobs out of the way. After the KOK, I moved on to a Muray 16mm editor/viwer. The big problem with these usually is finding a suitable lamp. I had previously made up an adapter so 12v 50w etc could be used, but found this was a bit too much for the film. Going down to 20w meant a new adapter. I had also tried and failed to make the festoon lamp at the front work - 12v versions are easily available as they are used in cars. These two factors stalled me, but I now have them sorted. Between the 2 adapters, anything from 10 to 35w (which is probably at the max that could be used) can be fitted. The lighting transformer used for the viewer will take up to 60w.

I have also been re-familiarising myself with the Ditmar Duo. I had given up at a point where the motor on an 8/9.5 model had been running very slow and there had been some burning/smoke. I suspected a coil fitted as part of suppression and had identified a spare coil when the complexity of fitting the damn thing overcame me. Without it, the machine wouldn't run and there it rested. 

When I got it out again, I looked again at how the coil was connected, using my 9.5/16 machine as a guide. The coil wires are incredibly thin and there are four of them, all to be connected in the tangle of wires on the rear of the paxolin board in the base, which was a bit daunting. (I shall add this to the end of the Ditmar page, which I have repaired, so you can see the pix.) The only suppression arrangement I have previously encountered involved a capacitor across the motor brushes, and now that modern electronics are not really worrried by spark interference, you can remove this sort of suppression without problems and the motor still runs fine. So I could not understand why this was not true of this coil. So I consulted my guru, who mentioned that coils like this could actually be part of the circuit, so naturally the machine would not run without it. I took a flyer and inserted wires to shot-circuit the two sets of coil wires (it's a double coil), This did the trick and I was back in business. This was where I found out that I had probably mis-diagnosed the problem in the first place, at least in part. The real problem was with the motor, which continued to get slower and slower and finally stalled. Unsurprising if this had in turn led to the issue with the coil in the first place. 
Luckily, I had a spare motor among my bits and pieces, tho' it was a real pain to remove the old one and fit the new one and finding all the right connections to make (being reversible, the motor has four leads).  Once I had the motor out, the problem was easy to find: lack of lubrication. I have not kicked myself too hard for this, since it is pretty much impossible to lubricate without removing the motor. It has ball race bearings at each end, and the only access is via holes where you would expect to find oil holes on a conventional motor with a simple brass contact bearing. However, the bearing race itself covers most of the hole, and lubricant would therefore need to travel along the side of the bearing, then turn a 180 degree corner to actually get into the bearing cage and do any good. You might think you have squirted stuff in, but it would have great difficulty reaching the right place. A piece of truly crap design. Once lubricated, a quick bench test with jump leads connecting to the projector showed it was working fine.


27th July

Since I last wrote here, my time has been taken up with trying to make my Rural Sonore work. In the end, I decided it would be more productive to set it aside for a while and return to afresh at a later stage. In the interim, I have been working on a KOK. Details are in Reviving a KOK.

30th May

I have now repaired the pages about the Bolex DA/PA projectors. They have come out a a strange hybrid of the old and new software. Page 2 follows old links that have transferred across, and has, unlike Page 1, retained nearly all of its original pix. Page 3 is now a Page 2 to Page 2 (I think) under the new approach.

28th May

bolex da_gear_003a      bolex da_gear_post37

Some time ago I had some replacement gears cut (in brass) for pre-1937 Bolex DAs (ist pic) and am now contemplating the same for 1937 onwards machines (pic2). The issue is of course fibre gears - these two are thin and prone to stripping some teeth. I can never accurately count the number of teeth, so hit on this method using an Adobe-type drawing programme.

I have had an enquiry from someone with a got-at Bolex DA who (brave man) is planning to make a new shaft for the clutch mech. I took a few pix and did some measuring, which I may as well add here.

dashaft1a     dashaft2a     dashaft3b     dashaft4a     dashaft5a          

The first row reinforces the importance of the small collar against which the spring holds the combination gear and dog clutch. This is held in place by a pin thru both sides of the collar via a hole in the shaft. It appears this pin is easily broken by over-tightening the external fixing. This arises essentially from a minor design flaw. To explain this. here are a couple of pix you may have seen before.

     bolex da_notch_mech_002b     bolex da_notch_mech_003a     Bolex DA_Notch_mech_004     bolex da_notch_mech_005a

The fundamental basis of the notching mechanism is a dog clutch, the two halves of which can be seen in pic 1 above. The inner half is fixed to a gear, but both halves are free to rotate on the shaft. When a notch passes thru the gate, the stirrup seen top in pic 2 and in situ in pic 3 pushes the inner end of the dog-clutch against the spring and so out of engagement with the outer half. This cannot follow because it is stopped by the collar secured by a pin. In pic 5 of the top row you can see this pin protruding - infact, it can't do this in use as it would foul the dog clutch, so it has to be a flush fit.

The outer part of the dog clutch has a square end which protrudes thru the back plate of the machine, and is then fitted with the square-centre washer seen in pix 2 and 4 above. Continuing to work outwards, next comes a spring washer (second from right in pic 4 above). This is a bit dished in shape so that when compressed it grips. This washer fits inside the dished cover (3rd from right in pic 4 and 1st left in pic 2, showing the two different sides). As can be seen in pic 4, this cover has two flats on its outer end, to assist in locknutting it against the final nut (left in pic 4). I think it is this process of locknutting that causes the problem - I am sure many people try to do it without two spanners, one of which needs to be unusually thin. Either the dished cover is over-tightened in the first place or during a bodged attempt at locknutting, which forces it up against the collar. Given that the dished cover is on a fairly fine thread, it can deliver a considerable force for relatively little effort, enabling it to break the pin. The entire thing is then disabled and at worse can cause the mech to jam up completely.

17th May

I last reported at the end of January on sprocketisation of my 35 to 17.5 film slitter. Thanks to the good offices of friends like Dino and David Cleveland, I now have a supply of unperf 35mm - probably about all there is left in the world. Yippee! I thought; then the problems set in. First I realised that a sprocketised slitter was nbg when using unperf film, so I had once again to re-configure the slitter, to work sprocketlessly. I managed this, so got out the perforator having put it away in what I thought was good order. Almost as soon as I started to use it however, than a key component became loose; the upshot was I lost all synchronisation between punch, trgistration pin and transport mech, as welll as pitch, and so far I have not been able to get them back.

Instead, I have been trying to do more repair work on this website. It is quite a complex process. In the Good Old Days I never worried about the size of images I used, and many were in the megabyte range. New software not very keen on this, so as well as finding all the pix, I have to re-process them to a more respectable size, preferably under 500kb, re-name them to match the naming conventions of the new software and help me to identify them when it comes to uploading. The pix then has to be uploaded in small batches and inserted one by one into the page. I used to be able to load in batches, too. My record so far is 100 pix in a single page.

15th April

Most of my time since the last posting has been spent on the verdammten Rural Sonore and the continuing effort to get halfway decent sound out of it. Recent efforts have included:-

1. A third, abortive, version of the sound unit, an attempt to make the sound optic move to and fro across the track on the flat, rather than by tilting as I have done up to now. It became onvious that this would require far more, and more accurate, work than I thought was worthwhile, so I stuck with version 2, ie using an L516 optic (I refuse to believe it is from a Son [ugh!], for obvious reasons).

2. I have re-located the pivot of the low sprung roller after the second sprocket.

RSsoundslide1      RSlowerspr

3. I have fitted a 110v AC  to 12v DC power supply in the base for the computer fan on the side of the lamphouse. This is on whenever the projector is connec ted to 110v.

4. I have built and installed, in the space where the motor capacitor used to be, a 110v AC to 4v DC power supply for the exciter lamp. This thing cost me hours of effort and angst. As you know, I am no electronics expert and could do nothing right with this unit, building and re-building repeatedly, then having to bypass bits of the circuit board where I had destroyed the copper tracks. It was an absolute nightmare - it kept doing imposssible things like the trimmer pot  which was to set the output voltage reading from low (but not low enough) at one end of its travel, via a higher voltage in the middle, then back to the number it first thought of at the other end. I finally got it done after repeated exchanges with my experts. This and the fan supply are both connected via trailing leads with DC plugs. Must find a way to differentiate or I will blow up the exciter lamp.

5. I decided it was worth trying the effect of tightening the springs on the sound gate (ex L516 as you know). I did this and the film kept jumping out. I was beginning to RSsoundunitdespair and to fear I would have to come up with a totally different solution. However, I first tried adding a sprung rubber roller and, finally, I have halfway decent sound, with good adjustment of the optic à la Vox.

6. I have done extensive other bits of fiddling, including boxing the power supply/ballast for an HID lamp and finding a way to connect it so that I can use the same unit for other projectors, changing both rollers on the top sprocket etc etc etc. I now have an even longer list of things to do to refine the sound and the physical performance of the machine. Which, if you are not careful, I shall share with you in due course.



23rd March

I have had a major diversion off piste with Rickmansworth and then an "artisanal" Gem 9.5 optical sound. Here is a pic.

artisanal gem_sofa

It turns out to be not a bad attempt. When I first tried it, the amp just howled, but this was quickly rectified when I found a broken earth connection. How ever, one of the ball bearings on the shaft with the flywheel and sound drum was seized; the shaft will turn OK but the bearing won't and I think this must have upset the sound. However, when I held the pinch roller tightly onto the drum - tighter than I think the present set-up will ever achieve - I got decent sound, if on the low side. Another good feature was the enlargement of the lens holder to old B&H size, much widening the choice and quality of lens that can be used. In fact, I have nicked this for my own Gem or maybe for a Son (ugh!) and replaced it with a spare. I am also tempted by the (constant speed) induction motor that has replaced the original.

The problem with this machine, though, is the quality of execution. It's a bit cobbled together and, worst of all, has been very badly overpainted by hand with gold Hammerite. The amp is functional but no-one could call it neat. However, if someone wanted to take it on as a project, an excellent result would be achievable, tho' with much work.

As for the Rural Sonore, I have tried out various things. Here is a pic of a re-work of the lower sprocket film retainers; this I made several years ago.

rs2ndspr3a

The shape of the arms was I think dictated by some bits I had left over from an attempt to make a direct copy of the original. It works OK but reveals an area I always struggle with - spacial stuff and rotation of shapes and figuring out how a thing will work. In this case, the problem is the bottom roller. It was intended to act as a spring-loaded buffeer for the take-up. However, when loaded with film, it simply does not function, but acts as a fixed roller. I guess it's something to do with where the pivot is, so I may have to re-work this, tho' it works OK as it is.

I also finally got round to trying out the machine with the latest incarnation of the sound head. I realise that the framing could be changed by using the bit of slack in the fixing of the plate that carries the fixed front gate. This is separate from the part of the mech with the claw so moves the entire aperture, both fixed and sprung gates, in relation to the claw. This really makes my brain hurt. However, there is now some unsteadiness of the film in the gate, so clearly more work is needed. I have also done a bit of crude bending and stopped the aperture plate moving with vibration when the machine is running.The sound itself is much more promising. There's a fair bit wrong with it, but it sounds as tho it is fixable. I need to replace the switched mode power supply I have been using with a proper, regulated DC supply and do some more fiddling.

29th February

Hmmmmmmmmmmm. Here is an update on the Rural Sonore. I fitted a 15v 150w dichroic mirror lamp (just using the same fitting as planned for the HID lamp) and found that, although there was light visible round the various joins, it was not substantial, due in part no doubt to the light being mostly reflected forward. The latest incarnation of the sound reader was a considerable improvement, tho' a long way from being good. A change of amplifier was part of the improvement; another change and the sound was actually approaching respectable. I have also installed the power supply for the HID into a metal box; the plan is connection via banana plug leads as I intend to use the same power supply for other projectors.

So much for the good news. Now that I have been running longer bits of film, a variety of issues have crope out from the woodwork. First off, the machine keeps losing the top or bottom loop, or both. I suspect this is due to a poor film retaining set-up on top and bottom sprockets. This will have to be corrected before I can examine other issues such as the sound head itself. Associated with this are various sound defects like warbling et al - hard to know if these are wholly loop-related or not at this stage. Also, volume is low, but my once-trusty pre-amp has let me down and does not improve the sound - level up, quality way down. Another problem is that both focus and the position of the aperture plate seem to be affected by vibration and so are drifting off. Framing is also off - I get a frame line at the top of the pic but there is no framing device (tho' I have seen cases where one has been fitted) nor any significant travel on the gate itself (unlike the Home Talkie).

One other issue. I found that the motor was being very lackadaisical about starting and getting up to speed, risking damage to the film. I therefore fited a separate lamp switch (for the 15v 150w supply, as the HID lamp will be switched separately). After discussion with a friend, I doubled up the capacitor and now it goes like a rocket. I still have some residual concern that this might damage the motor. Has anyone any experience or knowledge of this?

27th February

Here is the latest incarnation of the Rural Sonore sound reader.

rssd3     rssd3a

26th Febtuary

Here are the pix of the fully assembled lamphouse, which I think are broadly self-explanatory. You are very privileged to see these pix befpre I have actually tested it out - it may leak light all over the place (Iknow I shall have to do more with the fan) and/or generally leave me with egg on my face.

rslh07      rslh08     rslh09     rslh10     rslh11     rslh12     rslh13     rslh14     rslh15     rslh16

25th February

I lost another week to another bug, but have since moved on a bit. I told you of my adventures with the sound reader on my Rural Sonore, but maybe not why I wanted it. More on that later. The last thing I told you was about my efforts to use a festoon lamp, with limited success. After much head-scratching with the tthing on and off the machine, I came to the conclusion that the problem lay with the Elf sound optic. I just could not get it to focus unless it was so close tothe film it fouled the sound gate, which has a raised lip. I also reverted to a standard exciter lamp. Luckily I had one that was insulated; most rely on the mech for the return path, on which keen I am not. I found an alterntive - it might be from a GBL516 or maye even a Son (ugh!). I'll do some pix for you. To avoid fouling the lamphouse, which tips back just like a Baby or an "H", I had to turn it thru 90 degrees, requiring a different lamp with a horizontal filament. The Elf telescope holder was nbg as the difference in size (my new one is a tad smaller) was too little to allow for a sleeve. So I had to machine a replacement from solid aluminium. I also put some rough shikleding around the lamp to cut down on glare.

Back now to why I am pursuing this so determinedly. Your starter for 10 is this string of pix of a fairly innocent Rural Sonore lamphouse, which does not suspect what is about to hit it.

rslh01     rslh02     rslh03     rslh04     rslh05

Let me draw your attention to a couple of features. In pic 1, the notch at the top is where air from the motor fan comes in. Note the dividing wall to diect some air to the lamp and some across the gate to cool the film - another example of the superb design of the Rural. The lamp, incidentally, is a standard Vox lamp of 15v 200w. The lamphouse is pretty shallow; I have re-painted the cover, which simply slides off. Pic 2 is just a general view of the inside. Pic 3 shows past interference, probably to do with the conversion to 16mm during the war.You can see that the bracket on which the lamphouse pivots (see pic 2 for a different angle) is attached to the body by 2 screws. You can also see where it originally sat as an integral part of the main casting, to the right of that enlarged hole in the base. The front view in pic 5 shows how air is channeled across the gate. Pic 6 shows an important (to me) feature in the shape of a threaded hole. This is a relic of the earliest days of the Rural silent. On here pivoted a 2 stage douser - 1st part gauze for still, second part solid for full cut-off. A cycle-type cabe led from this thru the bottom of the lamphouse and round to a lever on the main shaft of the mech, just behind the pulley taking the drive from the motor. This originally pushed the drive pulley forwards, disengaging a dog clutch, with the pulley free to turn without driving the mech, to allow a still picture to be shown, while at the same time pulling the dowser into place. This mech had been disabled on my silent Rural and it is easy to see one possible reason why - how can you move the shutter out of the way with no means of turning the mech?

OK. I explained to you the problems I had trying to get the original sound reader to work, but I daresay I could have made it work. However, what I wanted to do was fit one of the discharge lamps described by Tony Saffrey in an article about a Specto in Group 9.5 mag, with the necessary douser, hence my long digression above. I have seen these lamps in use - they seem able, in some cases anyway, to outshine even a conventional Xenon. But this really requires a separate exciter lamp - I don't fancy scraping bits off the morror of a lamp costing £60 plus. However, this lamp is also deeper fron to back than can be fitted in the lamphouse I have shown you above. So I needed to find a way to extend the lamphouse, fit a cooling fan for when the motor is not running and fit a douser and a separate exciter lamp - all without making any new holes or other permanent alterations to the machine. This may be a personal foible, but I think there is a strong case to be made for keeping projectors as near to original as possible.

So now I have to go and re-assemble all the bits I have removed to show you where I started and do more pix.