Graflex.org

flammen1 · Joined: 16 Nov 2014 Posts: 3 Location: United Kingdom

I have bought one of these and am trying to service it. Am I meant to be able to dismantle this item? The top part does not seem easy to disassemble and I have had no luck trying to locate an exploded view or manual to help.

Markus · Joined: 13 May 2015 Posts: 15 Location: MA, USA

There is a Graflite service manual available that helped me figuring out how to disassemble my 2773:
http://www.southbristolviews.com/pics/Graphic/manual-pdf/GrafliteService.pdf

If you have an older version of the Graflite, maybe the basic design is similar?

flammen1 · Joined: 16 Nov 2014 Posts: 3 Location: United Kingdom

Thank you, Markus: that is much appreciated. The 1965 model has a black plastic component at the top which must have been designed for removal. The earlier model has a clamp to hold the bulb, held in place at the by a small rivet at the back of the battery holder. This is the part of the battery holder which I need advice on before I dismantle it. I suspect that light sabre makers saw that bit off but I am hoping that there is a way of removing the part under this clamp so that I can get at the inside of the unit. I would include a picture but it is not clear (I am new to this forum) whether I can include pictures here. Link to a picture on the web:

http://www.ebay.com/itm/Graflex-Graflite-true-Star-Wars-flash-synchronizer-battery-tube-/231607600263?nma=true&si=0Jp6jLx5LLM1MHe2UuA1FUA%252Bo9M%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557[/img]

45PSS · Posted: Tue Jul 28, 2015 7:38 pm Post subject:

flammen1 you have a Graflex synchronizer, the manual link is for the Graflite synchronizer. I know of no service manual for the Graflex synchronizer. The best bet to remove the socket rivet is to grind the head off or drill it out.

The only way to post pictures on this site is to host them on an image hosting site and link to them.
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The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

flammen1 · Joined: 16 Nov 2014 Posts: 3 Location: United Kingdom

WilsonLaidlaw · Joined: 17 Nov 2013 Posts: 13 Location: E. Sussex, UK

If it helps anyone, Paramount in NY http://www.paramountcords.com stock all the different flash cords for various Graflex flash guns. I just got a domestic 2 pin to PC coiled 3 foot cord from them - good and prompt service.

I have been looking at the service manual for the 2 cell Graflite. Am I correct in thinking that when used with 2 D cells, there is no capacitor in the circuit? The only time there is a capacitor is when used with the BC cartridge. That this would fire flash bulbs with no delay in heating the firing filament surprises me. This is because the Rolleiflashes (models I and II) and Leica CEYOO I have recently rebuilt, use a 22.5V A412 battery and a capacitor to add some "oomph".
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Wilson

45PSS · Posted: Fri Aug 14, 2015 7:32 pm Post subject:

A 22.5V battery only provides 140ma maximum current. Charging a capacitor then rapidly discharging it when the flash is triggered supplies the necessary current to fire the flash bulb. The higher voltage battery extends the number of flashes per battery.

A BC cartridge works similar, more flash per battery, lighter unit.
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The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

WilsonLaidlaw · Joined: 17 Nov 2013 Posts: 13 Location: E. Sussex, UK

Thanks for the information. I just felt that the firing of a bulb would be quicker if there was a capacitor in the circuit and I increased the battery voltage. Looking at the circuit diagram of the Leica CEYOO, as rebuilt by myself, on a 22.5V battery, it uses a 10K ohms ballast resistor and a 25 microfarads capacitor. I measured the peak current on an oscilloscope for the CEYOO on discharging the capacitor through a #5 bulb (6 ohms) at 2.8 amps, with an extremely fast rise time.

As I am using NimH batteries in the Graflite, with a total voltage of 2.4V, the current through the bulb would only be around 0.4 amps with a much slower rise time. If I modified the Leica circuit for the Graflite, with a 9V battery in place of the two D cells and a 5K ohms ballast resistor and say a 1000 microfarad/10V capacitor, I feel I might get more reliable firing and better timing. I would fit the whole thing inside a pair of D to AA convertors, glued together to make my own version of the BC pack. I don't want to use the 22.5V batteries due to expense and lack of availability.
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Wilson

45PSS · Posted: Sat Aug 15, 2015 7:48 pm Post subject:

The burn time and intensity has to do with the bulb design. A power source sufficient to fire the bulb has little to do with the burn time.
See http://www.donsbulbs.com/cgi-bin/r/t.pl catalogs are in the library by brand. Most type M flash bulbs used in battery powered synchronizers have a rise time of 15-20 milliseconds with a usable light output of 10 milliseconds.
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The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

WilsonLaidlaw · Joined: 17 Nov 2013 Posts: 13 Location: E. Sussex, UK

I agree that data but all that is after the bulb has fired, triggered by the heating of the filament inside. If one is only passing 0.4 amps through the filament, rather than say 2+, the filament is bound to take longer to reach ignition temperature of over 475ºC for magnesium with the lower amperage.
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Wilson

45PSS · Posted: Sat Aug 15, 2015 9:05 pm Post subject:

Look at the data table again. Type M flash bulbs require 3V to fire, no mention of current. These bulbs are magnesium fibers in a oxygen envelope. Once triggered they burn. Two 1.5V D cells provide ample current to fire them.
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The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.