Mark, yes, I know. Josh and I were talking about it earlier today. He has an old scrap Brenkert I gave him to play with, and I suggested he give it a try to see if he was more successful than I was. Actually, he was a little more successful in a shorter period of time, but he still had slight binding in some places as he rolled it through. (That's what I ran into when I tried it in my travels.)
The mating surfaces are clean of burrs, etc.
A couple of months ago, I demonstrated to Josh how critical those brackets are. I laid it over the edge of the table, and he held it in place. Then I put slight finger pressure on the other end of the casting, and the rear pinion had a very nasty bind and was almost impossible to rotate the pinion until the slight finger pressure was removed from the casting.
By jockeying the six screws that hold the shutter shaft casting in place, most of the time I could eliminate any nasty tight spots. After loosening the rear pinion collar Allen screws and tweeking, I was able to reduce the binding a little more. But that was the limit. There was still slight binding. After about 8 hours of screwing with this thing, I shouted an obsenity and said, "Close Enough!"
I wonder if Brenkert line-bored the shutter shaft casting after it was installed in the projector, and then assembled and installed the shafts and pinion gears into the shutter shaft bracket. By the way it looks, there is a good possibility it could have happened this way to maintain and keep the marvelous precision that has kept the Brenkerts running so well for over 50 years. Someone told me many years ago there was a lot of "hand fitting" of some of the the critical Brenkert parts. How true that is, I don't know. But it would not surprise me at all if it was.
I spoke with another tech, and asked about the varnish that builds up through the years in the shutter shaft parts. He suggested lacquer thinner will do an excellent job in removing the crud and varnish as long as nobody cares about the paint job on the shutter shaft bracket.
Josh, if Mark agrees with this, let it soak for 3 days or so in that stuff, and it should be easy to flush out. Give it a good bath, and don't let the bracket holes plug up with paint remnants. Then dry it off, and oil the hell out of it with your Brenkert oil. Don't worry about running out of Brenkert oil...I still have 4 gallons of that stuff for you in a 5 gallon bucket that I use as a telephone table.
Thanks for your input, Mark. I'll talk to Josh tomorrow and see how he is doing with the experiment.
Paul