Film-Tech Forum ARCHIVE: Speco brains scratching prints

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Posted by Jonathan Althaus (Member # 5042) on 02-27-2010, 03:42 PM:

I'm having issues with my speco's scratching prints. I have the older style brains with just 3 small rollers, then the angled large roller. There is so much slack in the brains that the film starts riding on the base plate, rubbing up against the rollers, causing vertical black scrathes on the right side on screen.

Any ideas on how to increase tension in the brains? Thanks for the help.

Posted by Brad Miller (Member # 2) on 02-27-2010, 04:12 PM:

Pass through the payout arm, through and around the first roller (skip the second one) and out the large one.

Posted by Jonathan Althaus (Member # 5042) on 02-27-2010, 04:52 PM:

I tried that on a couple platters a while back and the scratches seemed to go away and then they came back a few weeks later, so I went back to the normal threading. It seemed like the film had to ride on that inside roller just perfectly or would start scratching again.

Posted by Brad Miller (Member # 2) on 02-27-2010, 04:58 PM:

Your large angled rollers are probably not screwed down snugly or are screwed down at a wrong angle. I switched to that threading years ago and never had issues again after that.

Posted by Jonathan Althaus (Member # 5042) on 02-27-2010, 05:06 PM:

Ok, yeah some are loose and they aren't all sitting at the same angle. What is the proper position for those?

Posted by Monte L Fullmer (Member # 2797) on 02-27-2010, 08:34 PM:

I had the same issues with LP270 brains doing the same with both scratching and the angled roller shaft coming loose - which you gotta go under the deck and reach through with the philips screwdriver...and you're gonna need a helper on this one to hold the shaft while you're underneath tightening up the philips screw.

Thread through the brain and the film has to be laying square and flat and inbetween the roller flanges of the angled roller as the film leaves the roller and heads to its corresponding roller on the platter "tree". Or, you can say, that the shaft that holds the roller is leaning away from the "tree".

Posted by Darryl Spicer (Member # 711) on 02-28-2010, 12:26 PM:

I just removed the three screws holding the center feed plate down and then tighten the screws down making sure the angle of the 2" roller was facing towards the center hole. After I replaced the plate I would make final adjustments to the 2" roller if needed. By pointing the angle towards the center hole the final angle adjustments made did not loosen the screw. We also quit using Phillips screws and went to hex head screws so that we could get a better grip on the screw to tighten it down and not have the heads become damaged.

one other thing I always did was when I threaded I always made sure that after the film was pulled through the center feed, I turned the film so the soundtrack was to me when it went to the first roller on the tree, so long as the wind on the platter has the soundtrack up. I found that the film sagged less between the center feed and the first roller if you turned it that way than it did if you turned it the other way.

Posted by Brad Miller (Member # 2) on 02-28-2010, 01:14 PM:

Darryl has it down. The nice thing about threading with the soundtrack coming out of the brain from "up" on the platter to "away" from the tree is that you can go to the hardware store and buy longer bolts with hex heads on them and swap them out for the short stubby bolts. This way the film will sit about 2 inches away from the edge of the platter tree and static electricity from the film won't suck it up against the tree and cause scratching.

Posted by Jonathan Althaus (Member # 5042) on 03-01-2010, 08:04 AM:

Thanks for all the input. Hopefully I'll get all our brains fixed this week.

Posted by Jonathan Althaus (Member # 5042) on 03-01-2010, 01:49 PM:

I went in early and fixed and tightened all our brains. I already notice a major difference in the film path. Thanks for all the help.