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Arri III Problem

Published : 13th March 2005

Hello All,

I was recently on a feature where we were using an Arri III to do some pick-up shots and second unit driving shots. The camera was the DP's personal third generation, with a very late serial number. The 1000' magazines were rentals. For some reason, every time we tried to roll the camera with the rented mags with full 1000 loads, the take-up roller wouldn't run and the film would spool out within the first couple feet.

The first two mags I tried, both failed, but a third magazine, that was clearly a much later serial number (and the only mag without a collapsible core), took up fine. All of the film was factory sealed, and did not seem to be dishing or anything else unusual. It was a cold night exterior, but far from deep-freeze sub zero conditions, so I do not think that the magazine froze up. Also, the gear drive on all of the magazines appeared to operate fine, with the take-up spinning freely and smoothly off of the camera.

All the batteries were fully charged, and I made sure to try running the camera with and without accessories. While it had been a while since I been on set with a Arri III, I don't think the problem was in the threading, and I double checked the loader's work in the tent. When I tried the questionable mags with a much shorter dummy load, they seemed to run fine, but full loads froze up.

Has anyone had this sort of problem with gear driven magazines? Is there a difference in any way among the older Arri magazines? Perhaps variation in the pitch on the gear between mags made for a 2C versus a III or a difference from the first generation of Arri III to the latest? I guess, specifically, I am curious if there is a reason that the late model mag with the removable core seemed to be more compatible with the late model camera?

Has anyone noticed a similar issue with an Arri 2C/III magazine on a 435?

Thank you,

Matthew Santo
1st AC, Local 600, NYC


I believe the problem lies with the footage counter arm. (The older ones did not have variable tension). Doors were also subject to warping from heat.

John Babl
Miami


Mathew Santo wrote :

>the take-up roller wouldn't run and the film would spool out within the >first couple feet.

Greetings Matthew,

Sounds like the take up tension of the two first magazines you had problem with was not properly set. Had once a similar problem but cannot remember how to fix it. About 8 years ago, have not

Regards

SUYS Emmanuel


I own an Arri lll, it is most likely the clutch mechanisms in the mags themselves. The way you test it is to take the mag and manually spin both sides against the other. If the gear at the bottom doesn't move in one direction or the other it should be fine.

Gerry Brigante 600



 

 

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