Bolex G Series




I never quite took to the G3 (or its 8/16 and 9/16 dual-gauge stable mates), despite the plethora of bits and pieces, but inbolex g3a2 good condition it could be an attractive machine. This is a posh one with a strobe disc on the top sprocket.

Been pottering with a Bolex G9/16. When I first tried it, zilch. So I cut off the capacitor across the mains, presumably intended as a suppressor and now obviously defunct, and then we had some movement from the motor, but very little. Next was to open up the back and take a toothbrush dipped in white spirit to all the aged, dried grease caked onto the various gears, and re-lubricate. This gave more movement and, left to warm up for a few minutes, the machine managed to reach a nearly respectable speed. I then moved on to do the same with the claw and cam, and finally got the sort of speed response one expects. Only problem then was the lamp. The switch is set up to be automatically tripped off by the motor switch when that is turned off. Only it didn't. Issa bit of a bugger to get at - you have to go from below and by removing the side switch panel, to get even very restricted access. I tried all sorts of lubrication, but nada. I eventually found that the lamp switch, which is a large push-in button at the back of the machine, was binding. The button passes thru a collar; the button is plastic and had distorted just enough to banjax the operation. Instead of springing out once pushed in, the button stayed in and provided enough extra resistance to stop the interlock operating. I just bored out the collar a bit and smooth operation was restored.

I have come across a G3 variant that hadn't really caught my attention before. This has a special speed control that appears to allow a steady

bolexG3fixedspeed1 speed to be maintained at anything from under 16fps to 24fps - a variable fixed speed! The control is on the frontbolexG3fixedspeed2 of the mechanism, and connects to a complex set of make/break contacts, cams and coils. These are in turn linked to a resistance in the base. See pix; nb the two small coils are on a board I have detached from its mount to see behind it. In the first pic, the speed control knob can be seen top left - you can just read the 24. This links to some contacts (just below and to the right of the knob) which are also connected to an arm with a spring, seen near the shutter. This arm has a pad which rides on a hexagonal section of the main vertical drive shaft, giving an oscillating motion. Below this, with the green wire, is another set of contacts linked to the standard Bolex still picture mechanism lever on the front side of the machine. (The knob lower left is the gauge-changer).

Now, this may all sound a bit confusing - well, it is to me - frankly, I can't make head nor tail of it, so it was back to tried and tested methods, viz "poking about a bit to see what happens". The speed control wasn't working when I got the machine, it just ran flat out and the speed control did nothing. I cleaned the contacts as best I could. The only other thing I could think of that I understood at all was to replace the condenser/capacitor, which can be seen mounted just below the coils. People who understand such things tell me condensers can fade with time, so for the sake of about £2.35 at Maplin for an 0.1 muF capacitor, I replaced it and Lo! the projector worked fine. I have run several films thru now and I am much more impressed with it than with previous G3s, good steady picture and nice constant speed. The only snag is the tilt mechanism knob on the front is placed in just the right spot to make it difficult, but not quite impossible, to get a 900' reel onto the spool arm. 1000ft wouldn't fit at all; it hits the main base of the machine. As to why such a machine was made, I read in Andrew Alden's Bolex History that Bolex themselves, as well as other companies, made add-on sound units for silent G3s, so it might be connected to that.


I think I have mentioned before that I am not impressed by the Bolex G series of projectors, principally because there is no springing to the claw and virtually none to the gate, so if a film gets out of rack, especially 9.5, we are talking holes in the film or severe denting and scratches as there is no slack for the claw to slide over the film until it reaches a sprocket hole. I had a G3 with only 400' spool arms, only 9.5 parts and already significantly hacked about by a previous owner. I saw little chance of getting a decent working machine out of it, so I have dismantled it. One thing I was interested to see was whether, if such a bizarre set of circumstances arose, one could transplant 800' arms onto a 400' machine. Here are a couple of pix of the mech, with the arms removed or part-removed. It looks to me as tho' it could be done. I kept various spares just in case - I think I've managed to convert the G3 9.5 spindles for a Bolex DA, as these are often missing their 9.5 parts.

G3 mech1     G3 mech2


Anyone interested in Bolex should see Andrew Alden's books (see Books under Miscellany.)