Multi-Gauge
18-02-14
MULTI-GAUGE PROJECTORS AND STUFF
One of the recurrent themes of the 50's, 60's and 70's was the so-called "Gauge Wars". With 8mm, 9.5mm and 16mm all contending for the amateur and slightly beyond market, much was made of the comparative picture area and other features. Each gauge was insisting it was the best, (does this remind you of the nonsense over digital v. film?), whereas the more sensible among us took as much of everything as they could get. One of the side effects was the proliferation of multi-gauge machines, so that it seemed most manufacturers had one or more machines of this type. I have always been fascinated by multi-gauge machines. I especially like all those interchangeable bits. I don't really count 8/S8 machines as multi-gauge, tho' the Eumigs for instance have nice interchangeable bits.
Apart from projectors, there are various topics not tied to specific projectors or gauges that it is convenient to group under the M-G heading. So we have simply:-
M-G PROJECTORS and GENERAL TOPICS plus some shorter bits below
Rewind Adapters and a Multi-Gauge Long Play Unit
I've been making some adapters for the Muray multi-gauge rewinder. Previously, I've stuck to 9.5mm, but I decided to give 8mm a go. However, this is all very time-consuming, so I thought I would post details here so other people can make them rather then me. You may recall that I also made some adapters to handle 17.5mm (see photo), see in Big Brother 2.
The first two pix deal with the run-of-the-mill adapters. I made them just to prove to myself I could. The 9.5 are the easiest; the Std 8 and 16 are the hardest. I used steel for the 16 - I only made the one - as I didn't think aluminium would be strong enough - I think the originals are made of some stronger alloy. Steel makes for harder and slower work. Details of how to make them are given in the diagrams in the second row so people could make their own. I did these a) to help me remember how to do it (I use my website a lot for this) and b) because I don't want to spend time making them myself.
The rest relate to my special interest gauges, 17.5 and 28. I made 3 attempts at 17.5, the first admittedly being for a 35mm rewind, not a Muray. As you can see in Pic 3, it was just a 16mm camera spool with an appropriately placed pin to engage the 17.5 spools. The same thing also served as a spacer outside 16mm spools when I wanted to use the 35mm rewind for that gauge. My second attempt was basically like 9.5 adapters, with a sleeve to take the spindle on the Muray from 6mm to the 8mm of 17.5. As you can see, the sleeves were entirely separate. The problem was they kept either sticking inside the bore of the spool or even disappearing inside the spool core where the spools had no through bore and simply relied on the two side cheeks acting as bearings. Cheap and nasty. My final effort to date is in pix 5&6. Finally, the 28mm ones are different in that, in order to accommodate the much wider spool, the sleeve slides in from the outer end of the spindle and into the gap between the spindle and the spool core. It is held in place by screws that go onto the flat bit of the spool retaining clips. I hoped to might be possible just with the knobs shown but it didn't really work - not enough space to turn them - and I reverted to ordinary screws and a screwdriver. I must get around to making some knurled knobs so I don't need the screwdriver. The spool retaining clips I mean are the spring-loaded ones at the end of spool arms that flip ninety degrees to hold the spool on. There is a pic that shows this on an experimental version below.
John Collins bought a Eumig Super at Harpenden, a 9.5 machine but which had somehow acquired a set of 8mm arms instead of 9.5. It was relatively simple to fix, as all that was required was a change of spindles - I copied those from mine (a Super re-badged as a Pathé Rex). Finding a way to keep the spools on was a challenge, which I ducked by slightly lengthening the spindles and cannibalising a Kid Super attachment for the slide-on retainers that are a push fit, yet rotate freely once on. However, having completed the job for John, I thought I would have a go at making a conventional spool retainer, ie the ones where the end is a pivoted strip that flips 90 degrees, with a spring providing a bit of tension to hold it in place. Fiddly, but I made one as a test that would undoubtedly work. Will try to do a pic.
Multi-Gauge Long Play Unit
This started from a sudden spurt of interest in Standard 8 and segued, via an excursion into some sound experiments, into the appliance of the title above. I have had two such units before, both only 16mm and both, I think,of Elf origin. One was the tower with side-by-side reels behind the projector, the other was two separate arms mounted on a huge base. Neither was attractive to me, so I sold them on, but when Bryan Pearce tempted me at Harpenden I fell for his spiel, but had never yet (the time was April 2020) got round to using it. Now read on.
Over the years, for a variety of reasons and usually as incidental to other deals, I have accumulated a fair amount of Standard 8, for which I have a sneaking fondness. Much of it is on super-size reels, designed to be shown on a Heurtier Superson with extended spool arms. Now, I am a little wary of the Heurtier when it comes to mag sound. The heavy sound smoothing of the Universal is still in play, to which mag adds the drag of passing thru sound heads which, in the case of the Heurtier, seem to be rather firmly sprung. I cannot but feel that the total tension on the film is worryingly high. This may seem and quite possibly is a bit fussy, but it has led me to explore once more the good old original 8mm machines, of which I have basically two in reasonable working order.
The first is a Eumig Mark S 709 dual gauge machine. I have to say this is pretty impressive for an aged Eumig - none of that slow running in either forward or reverse and a surprisingly bright pic, admittedly at 8mm distance from the screen so a smaller pic. The first film I tried to run was a 5 x 400' version of Second Chorus, a decidedly so-so musical starring Fred Astaire, Paulette Goddard and George Murphy, together with Artie Shaw and his Orchestra. This immediately led me into issues of sound quality, most of which I think were down to the print rather than the machine. I cleaned each reel before showing, which seemed to help (after first trying one reel uncleaned). I then turned my attention to other measures, first trying one of the old Craven in-line speaker controls, a simple one for tone only (You will have gathered I was using an external speaker). This seemed to help some, but the sound was a bit harsh and distorted, although dialogue was very clear. Next was to add an external amp, which ended up giving decent sound, if not of the highest quality.
At this point, the Standard 8 strand collided with another strand I was playing about with, ie using a Bluetooth speaker rather than a wired speaker to produce film sound. I was looking at this because, as many of you will know, I often set a projector up with simply a photocell/diode and a connector for an external amp or, I thought, perhaps an amp at a wireless distance. One can imagine this being useful for shows, avoiding the need for trailing speaker wires. Not so much use in the home, but I just thought it would be fun to play with and maybe learn a few new things.
The first thing I learned was that I needed a Bluetooth transmitter and possibly a pre-amp to ensure adequate sound level from a diode. The final requirement was a Bluetooth speaker. These are of two types, those with a built-in mains-charged lithium battery, designed for portable use (and very frequently emphasising their waterproofness) and those operated direct from the mains and so essentially domestic machines. These were available in all sorts of shapes and sizes, but it seemed to me if I wanted to have decent sound I would need a mid-price/budget one rather than a very basic toy. This made me gulp a bit, as I didn't know if all this would work. Fortunately, a daughter imported for viral reasons had a rather-better-than-basic speaker, so I was able to test the principle without going OTT on expenditure.
Well, the principle worked, but in practice there were problems The sound was coarse and distorted at anything above modest volume and I had huge problems with connecting things together. Some of the first problem might well have been due to the connector problem, but there might also be an issue of matching the various bits of kit. I had bought a fairly small (tiny even) transmitter, which may not be person enuff for the job. Incidentally, there appears also to be a technical issue affecting matching sound and picture, or sync as we would say. Apparently, Bluetooth transmiters (and maybe the amps, tho I am not clear on this) could vary and fall out of sync with the picture. This is a known problem and several systems for minimising this exist. The one I picked up on was aptX, which both transmitter and speaker must be designed to handle. It increases cost of course. Where it's only a question of reproducing sound, the sync does not matter of course.
Anyway, back to connectors. I ran my initial tests using a (very ancient) portable CD player. The problem was that both CD player and pre-amp were designed for stereo, with different connectors - 3.5mm jack for CD and 2 x RCA for the pre-amp. As I was only looking to deal with mono sound, I had wired the two signal inputs to the pre-amp together. I did not have a stereo 3.5 jack to RCA phono lead, so was forced to fall back on those mini converter plugs that can do the same job. This where my trouble started. Here was I trying to connect a 3.5 stereo jack to 3.5mm stereo jack lead from the CD, to the pre-amp, using a RCA to stereo jack connection converter, to a mono input on the pre-amp. These connections did not work well and only by moving the connector/connection about was I able to get sound thru at all.
I had already encountered similar problems trying to run the Eumig 709 thru an external amp. The official way to do this was by using a properly-wired 5-pin DIN plug from a socket on the projector, but so far nothing I have tried can raise a peep out of this route. I did get somewhere by using a 3.5mm stereo jack in the earphone socket. If I wiggled the plug about (probably more than one plug as I needed to stack connectors to get the right connections) sufficiently there was a sweet spot that worked, as long as you didn't knock anything. I tried a mono 3.5 jack, reasoning that the projector must be mono, but couldn't get it to stay in the hole properly or make any kind of connection. In the end, my brain started to hurt so I called a halt for the time being.
Later, I turned to my second machine, a genuine classic, a Mark S Standard 8-only machine. I have found that this and related models often suffer from deterioration of the lubricant and the performance of the spindle-to-rubber-wheel motor drive, so that they run slowly or the mech doesn't move at all, particularly in reverse. This particular machine is one I have attempted to re-lubricate in the past and altho' initally slow, it soon regained normal speed after being run for a while with the lamp on. Reverse took longer, but eventually regained most if not all of its speed. I was able to run a test reel thru using the internal speaker only and got excellent results. The 709 had no slowness and a rewind like lightning. The final point about these projectors is that the way forward for me, rather than re-spooling lots of spooled-up films onto reels that I do not got, may be to use a long-play device. I acquired a 16mm one of these from Bryan Pearce a few years ago, which he had made from a re-fettled and improved Craven - actually, I think I mean Cresta Electronics? no, I don't, I mean Spondon - machine. I had yet to try it and thouight this might be the time. After all, conversion to 8mm can't be that hard?
Nothing is, of course, ever as simple as it appears. I dug out the long-play unit and then my troubles began. To start with, it had spool spindles designed only for 16mm, which is about the last gauge for which I might use it. Std 8, yes, Super 8, yes, 9.5, yes, 17.5, yes. But not 16mm - I basically gave up on 16mm film some years ago and I don't think I have any left long enuff to need an LP Unit. My first thought was to make some adapters to fit over the 16mm spool noses and, after some fiddling, I achieved this and could use both Std and Super 8 spools, using adapters based on the Muray type, but truncated to cater for the fact that the LPU spool spindles worked by holding reels on with a big knob engaging with a thread on the spindle (note this for later reference), so the adapters didn't need the extra length provided for the slot in the outer end of the 8mm adapters, into which the fold-over spool retainers on the Muray fitted.
The next thing I did was to get out a spooled-up 8mm film , which turned out to be on a slimmed-down 1600' reel. Only it was a home-made conversion of a real 16mm reel, with a 16mm core. This would not of course fit my new adapters; more important, it would not fit the 16mm spindles because, apart from the usual square bit of a 16mm nose, the rest of the spindle dwindled to 6mm for the threaded portion and the reel in consequence just drooped to the side. As originally received, there were extra bits of square section tube to fit over the 6mm bit and prop the reel up, but these were too long for the cut-down spool (because the big knob would only work properly if up against the reel itself) and I had to make a new shorter one - I just used round section and I only needed one as I could use any spool at the other end.
Then I thought, why don't I go the whole hog and convert to Muray adapters and so have a multi-gauge LPU? I was well into this new project before it was borne in on me that I would have to either cut down some adapters or make new, shorter ones - I have often made spare Muray adapters for my own use or sale, so this is just a bore but not a problem as such. And the length would need to be carefully adjusted to ensure the big knob would butt closely enuff against the reel to hold it firmly. Which it won't as reels are all different (and 9.5 ones have that protruding little bit just around the spindle-hole), so I shall probably have to make a batch of custom washers to use for various gauges. Later examination made me hope this would apply only to 8mm and 16mm and that maybe I might even be able to re-purpose my existing 8mm adapters, which I had made earlier on in this process. This proved mostly right; I had to slightly adjust the 8mm and Super 8 bits, and cut off the slots for the 16mm adapters nearly completely, but my existing 9.5 and 17.5 adapters seem to fit OK, tho' I need a washer for the 9.5 because of that sticky-out bit. It meant of course that I had to make entirely new spool spindles, copying the originals at the inner end and copying the Muray type at the outer end, adapted for screw thread reel retainers.I ent decided yet what to do about the guide rollers on the spool arms.
The other problem I have found is that the wooden baseboard of the LPU has various intrusions which mean the available surface is not on one level. At each end there is provision for the horizontal, L-shaped bases supporting the upright arms (that carry the spool spindles high up), to slide in and out between wooden guideways (using Big Knobs again), presumably for adjustment. One has about twice the travel of the other. There are also strips of wood either side of the wooden base, raising the level at the sides. Not sure why as the big knobs still get in the way as they are higher than the wood strips. What it does mean, however, is that the platform is not notably suited for 8mm machines, especially ones with a single front foot. So I shall have to make a supplementary platform to cover the whole area (aside from the horizontal adjusters) and provide a nice flat platform suitable for most projectors. And did I mention that there are two 16mm guide rollers on each of the uprights? Not sure if I can leave these as 16mm or have to custom-make some.
And yes, I can see that much of this is not going to make much sense without pix so I shall see what I can do. I told you nothing was ever simple.
First we have the baseboard as received - the underside is flat and covered with red (!) felt. Second is the complete unit with 6000' 16mm spools in place. Pic 3 is the simple control panel/mains input. 4 and 5 are the two sides of my supplementary baseboard. 6 shows how one of those big Fumeo 8mm spools looks - they are about the biggest I know for 8mm.
As to pic 1, I do not know why the two ends have different lengths of adjustment. Nor do I know why, having initially made holes for the bolts for clamping the arms that are equidistant from their respective ends, one was subsequently moved closer to the end. These fittings arrived with only a small washer between the big knob and the L bracket; I decided a big knob should have a big washer. Ditto with the fittings where the L brackets meet the uprights. In pic 2, you can see that the arms connect to the baseboard via these L-shaped brackets. You can just see behind the uprights the edges of the big knobs and, at the front, the heads of the bolts to which they connect, that clamp the upper arms to the lower bracket. Note that under the outer end of the L brackets, directly under the uprights, are blocks that support the brackets so the outer end is at the same height as the baseboard. I do not know why the two spools are at different heights, tho' I spose it's based on a 16mm projector and the route the film takes. Note there are two guide rollers for the right-hand arm as well as the left, but one is hidden behind the spool. There are holes for these rollers at various heights. Pic 3 shows the controls, with the DC power connection at the bottom. I think there should have been an arangement for the motor to plug in at the top and for the socket to connect to the power input, but the motor is actually hard-wired and dangled about a lot on its wire when I had to remove to to fit a new spindle.The motor seems to me to be tiny for the job it has to do but Mr Pearce assures me it works. The top switch is labelled tension; it seems to me this label belongs with the adjusting knob above it, because the switch is really just on-off; it needs to be on for the normal take-up to work as it does for the rewind when this is switched on. Pix 4 & 5 are the two sides of my supplementary baseboard, which I made to form a more user-friendly base for 8mm machines; this is before the final coat of polyurethane varnish was applied.