This is topic Vertical shaking in Ballantyne Pro 35 in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Darren Fox (Member # 1361) on 10-05-2002, 02:43 PM:
After many months of lurking and pulling knowledge from this wonderful website I am finally forced to throw out my problem. We have a Ballantyne Pro 35 that is having a shaky image problem. The image is shaking up and down. We recently replaced the framing coupler in an effort to fix this problem. I have removed the film gate and cleaned it completely. Everything looks to be in good shape in there. The gate tension has been all the way up and down and everywhere inbetween. Nothing seems to help. Any assistance would be greatly apprecated with this problem. No customer complaints yet about the shakiness but I feel if the presentation ever hits the point of customers complaining then the problem has been ignored way too long.
Posted by Paul G. Thompson (Member # 655) on 10-05-2002, 02:55 PM:
Put your finger on the outboard bearing arm of the intermittant sprocket and see if it is "throbbing". If you feel any hammering or clunking whatsoever, that assembly has to be rebuilt. Check your gate tension and accentric screw to make sure it is adjusted properly. Make sure the outboard bearing thrust screw is set properly.If none of the above seem to cure the problem, more than likely you have a bad movement. I know of nothing else that will cause the problem. Some people have installed "Disney" couplers, and it has helped substantially.
A friend of mine who is running PRO-35's told me recently that when a rebuild movement was instaled, the picture was as steady as a rock.
Hope this helps.
Posted by Rick Long (Member # 213) on 10-05-2002, 02:59 PM:
I agree with Paul. If it ain't the coupler, it pretty much has to be the intermittent movement. Nevertheless and this is a long shot, I had this happen with a Pro-35 once, due to a loose rear lens element. Just a thought.
Posted by Paul G. Thompson (Member # 655) on 10-05-2002, 03:16 PM:
I might want to add this - the spline shaft for the intermittant movement and the actual sprocket spline shaft could be worn excessively because of people misusing the framing handle. The bearing end of the sprocket spline shaft could be worn undersized, also - especially if the shaft has been slipping on the bearing. If the above items are true, you can install couplers until you are "blue in the face" and your problems will not go away.
Posted by Darryl Spicer (Member # 711) on 10-05-2002, 03:29 PM:
Also check the lateral guide for groves. Rotate the little square to a smooth spot. I have had latteral movement resolved by doing this. Dirt build up in that area can cause problems too.
Posted by Pat Moore (Member # 380) on 10-05-2002, 04:31 PM:
Most of the bases are covered, it seems. Paul is absolutely correct -- if it is an older PRO35, the Star and Sprocket shafts that meet in the coupler could have been beating each other up, leaving sharp edges on the ends of the shafts that rip the coupler up when you put it on and every time you frame it afterwards. Most have been designed so that only the centers of the shafts meet and not the machined splines that match up with the coupler.When you check that outboard bearing assembly, have people been after it with a pliers to try and tighten it up? That knurled screw on the outside should just be snug -- it's purpose is to keep those two shafts together and not allow any lateral play. If it's over-tightened it wears the bearing out in the intermittent. If it's too loose you'll get the picture jump you mention and the projector will probably be noisy.
Is that outboard bearing assembly silver or black? The black one one is the newer design and much, much preferred.
Pat
Posted by Darren Fox (Member # 1361) on 10-05-2002, 05:08 PM:
Thank you everyone for the extremely quick replies! Historicaly, maintainence in this theater has been slim to none until a big problem comes up. I will try out the various ideas. In answer to Pat: the outboard bearing assembly is silver and yes it has little plier gouges on it. Also, we've had some projectionists in the past who would use the framing lever for all of their framing instead of the window so I know that whole assembly probably isn't too happy.
Posted by Kenneth Wuepper (Member # 1174) on 10-05-2002, 08:30 PM:
Hello, Darren,I saw a Century projector which had been changed from a 3 blade to a 2 blade shutter and the manager/operator sent back 2 prints of "On Golden Pond" because they were jumping on the screen. The real problem was shutter timing was so far off that you could see the image moving on the screen. Yes, there was a lot of travel ghost in the credits but he didn't notice that at all.
Is the shutter timing off?
KEN
Posted by Shaun Flichel (Member # 1435) on 10-05-2002, 09:09 PM:
ON the Pro-35, are you sure the gate tention is tightening far enough? The knob assembly you use to open the gate can also be adjusted, you may try this also as you might not be getting enough tention and therefore a jumpy picture, if that fails, then yes, your suspect is the movement itself.Shaun
Posted by Pat Moore (Member # 380) on 10-06-2002, 08:45 AM:
Good catch, Shaun. Sometimes the obvious things are missed. Generally the PRO35, like any other projector, should run with very light tension from the film Gate. An eccentric screw allows this pressure to be easily adjusted while running. Tighten it just enough to steady the picture, and that should be the point where film noise gets quiet.One note -- light pressure in the Trap area generally causes a random "jitter" of the picture. If the movement is very rhythmic and regular, it's projector/mechanical or the film print itself. Seldom would you see such movement from a print on all reels and it sounds like this has shown up on all films, right? So we're probably back to the projector.
If the theatre has the money, that new outboard arm assembly for the PRO35 (sorry, can't remember the part number offhand) and a coupler will fix the problem. If you're good mechanically, then the coupler can probably be rebuilt without buying that whole assembly. But heck, you'll need to be pretty good mechanically to change that outboard arm, too...
Let me know how we can help.
Pat
Posted by Mark Gulbrandsen (Member # 72) on 10-06-2002, 09:54 AM:
Is this happenning all the time or just when the express train passes by your theatre on its way to the next station???
Seriously though I have changed alot of couplers and rebuilt alot of intermittents/outboard arm assys in the past 10 years. If you increase the film tension at the gate and its still shaking/jumping then it is likely that the coupler and outboard arm need to be rebuilt. The plastic coupler piece and bearings are not that expensive, but a bit touchy to set up properly inside the coupler casing. If this is allowed to continue it will likely keep hammering the spline shaft against the outboard arm ball bearing and damage(mushroom) the end of the spline shaft. If you pull the outboard arm off to disassemble it and the spline shaft will not slide out through the bushing easily then this has happened and you will also have to replace the spline itself. Be sure to file the mushroom part off before taking the shaft through the bushing or damage to the bushing will also result. Just had this happen to a machine a couple of weeks ago.
Mark @ CLACO
Mark
Posted by Jon Bartow (Member # 241) on 10-06-2002, 09:07 PM:
I realize that you just changed the coupler, but with the last few that I replaced I rejected 2/3 of the new ones from Strong (no offense Pat) because they came in with cracks in the plastic part. The cracks were very hard to see, but they were there. I tried one that had these "micro-cracks" and it caused a jumpy picture. Put another new one in with no "micro-cracks" steady picture.So the short version : check the coupler that you put in and possibly try another new one
Posted by Greg Pauley (Member # 503) on 10-07-2002, 12:37 PM:
"Some people have installed "Disney" couplers, and it has helped substantially"Paul,
What's the deal with the Disney coupler? I knew that Disney did some modifications to their Pro 35, but wasn't aware they had a different coupler.
Posted by Paul G. Thompson (Member # 655) on 10-07-2002, 12:50 PM:
Greg, to prevent myself from speaking through my butt, I'll let Pat handle that one.There is a difference, but I frankly don't know what the difference is. From what I understand, they do perform better.
Posted by Tim Reed (Member # 137) on 10-07-2002, 12:56 PM:
I thought the Disney machines HAD NO couplers? That was why they worked. Of course, you can never have an out of frame with that kind of arrangement, but hey... Disney's perfect! 
------------------
Better Projection Pays!
Posted by Pat Moore (Member # 380) on 10-07-2002, 01:11 PM:
Jon et al;This is the first I've heard of micro-cracks in the coupler bobbin assemblies -- the nylon piece that is actually inside the coupler assembly. I'll investigate but hopefully I would have heard of something like that before now. Those are a part we get from LaVezzi and their stuff is usually dead on right. I assume the problem pieces were returned. What time frame was this?
We build several versions of machines for Disney. One is a "Solid-Shaft" Ballantyne that eliminates the coupler -- therefore it's a non-framing mechanism, great for continuous, heavy-duty endless-loop use that Disney does. We build framing types for them as well. The improved coupler was our design to improve performance. The splines of the coupler are elongated so there's a larger mating area of the nylon bobbin to the two shafts. Performance is much improved, but framing is limited to less than two perforations, as I remember. The performance is worth that problem in a well-run theatre where framing should hardly be an issue.
3951 is the standard bobbin in the 62-31-59 Coupler Assembly.
3951-1 is the heavier bobbin used in a 2260675 Coupler Assembly.
Hope this helps...
Pat
Posted by Don Sneed (Member # 955) on 10-07-2002, 09:41 PM:
Jon, that crack you saw do not mean a thing, I serviced & rebuild countless number of Ballantyne Pro-35, the coupler spline cracks or broken plastic inside the coupler don't matter, it is very thin, the thing to look for is the little round plastic on the ends of the spline that goes around the spline to secure it, if they are missing the coupler will cause a jump...I make a habit to watch my oil for any gear pieces or these small white pieces as I drain the oil...if you see anything in the oil, start looking at the spline, intermittent gear & shutter gear....If you replace just the spline, be sure to notice the indention spot on the spline & put the new one in the same way, after I rebuild the coupler I also seat the coupler to the intermittent & sprocket shaft a few times before installing the assy. this will help you to easy install it without damaging the new coupler which is easy to do...I don't worry about the broken or cracked thin plastic on the spline, I gotten new ones from Strong this way, the important thing is the several small white thingly that holds the plastic spline to the metal...one thing I learned in the 22-years of service work, on a Pro-35 the damage comes from excessive framing, this wears out the intermittent & coupler...learn or have all the projectionist to frame the film in frame without using the framing handle...you will get years of life out of these two parts...I use to cuss these machines until I learn I can make a lot of money repairing these machines...now I love them....Thanks Mr. Ballantyne !! All joking aside...these machines are good if you listen to what have been said in these post...the Pro-35 has 5-problems that alway comes up every couple of years, once you know what to look for & their cure, these machines will run & run...I have machines I service for over 20-years, replaced the intermittent & coupler (spline) due to the projectionists will not thread the machine in frame, I have a 6-plex with these machines, the projectionist threads in frame every time, I only replaced these two parts twice in 20 years....Good Luck....
Posted by Greg Pauley (Member # 503) on 10-09-2002, 07:10 PM:
PatIs the heavy duty bobbin used in the black coupler and the standard in the silver?