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Topic: Strange Black "Snow" on One Side of the Frame
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Monte L Fullmer
Film God
![](http://www.film-tech.com/ubbmembers/2797c.jpg)
Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004
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posted 09-09-2005 03:56 PM
Look at your pad roller assembly that covers the middle constant speed sprocket - the sprocket that is right after the intermittent (mainly for the Simplex, but other domestic makes as well) assembly that gathers the lower loop of film.
Look at that front (left) roller - the roller that is at the head of the pad arm assembly and the roller that the film touches first. If the front roller has what's called "shoulders" - it's a smaller diametered inner flange that the sprocket teeth passes through between this inner flange and the outer flange of the roller.
What happens is that, if the bottom loop is built too big and I've seen it happen with almost normal sized loops, the film rubs against this inner flange causing these linear scratches, on the base side of the film, to appear.
Order some non-inner flanged ("shouldered") rollers and replace the shouldered ones with these rollers. This will eliminate this linear scratching.
Also, adjust the pad arm assembly to where, with two layers of film over the sprocket, both rollers should still turn freely. If the assembly is closing too tight, this is major cause of linear scratching, since the rollers aren't turning freely, plus major wear on the rollers.
thx-Monte
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