This is topic Sound Warble in Simplex XL in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Dave Williams (Member # 299) on 09-20-2001, 12:08 AM:
I have four of my Six Simplex XL's with a bad sound warble on the optical. The film bounces very badly in the loop around the sound drum. The problem is severly minimized when we take the slack completely out of the sound head and run with one sprocket past zero tension.I have seen this problem discussed on christies but what causes it on the XL's and what can I do to repair the problem?
Dave
Posted by Paul G. Thompson (Member # 655) on 09-20-2001, 12:25 AM:
Dave, what vintage of Simplex Sound head do you have? If it is a SH-1000 or a 1004, check the scanner shaft bearings. It could be possible that the shaft speed could be low, as to compared with what it should be running at. Also, check to see if the lateral guide bearings are not frozen, or rough. Does the lateral guide roller "bob" up and down? That will show crappy cushion roller in the lateral guide assembly.If you are running a belt drive, such as the 5-star uses, look at the fluctuation of anything that may occur at the snubber rollers. That could give a clue.
If sound warble is present, it is due to something dragging, impeded, or something just not turning at the desired RPM.
Check the scanner drum. I have a tendency to believe that it might not be turning at all, or very little. The cover on the non-operating side is the shittiest in the industry (With the exception of the RCA-1040) and could come in contact with the rotary stabilizer).
Now, if four of those have the same problem, you may be threading your sound head TOO TIGHT! You have to have some slop. On the 1000's and the 1004's, have a MINIMUM of 1 sprocket hole of slop when the guide roller is closed. Nominally, it is TWO! It depends on what your tech used for slop when he calibrated your system.
Paul
Posted by Dave Williams (Member # 299) on 09-20-2001, 02:13 PM:
They are the sh-1004 variety. WHen the slack is loose, one or two sprockets worth, that is when the bounce and the warble occurrs. I am tending to side with shaft bearings. I have checked them all and they are very tight. I am guessing they should be very loose. Would the bearings in the drum shaft cause it to run too slow and cause the bounce in the film loop?Dave
Posted by Paul G. Thompson (Member # 655) on 09-20-2001, 08:12 PM:
Dave, I would recommend you open or remove the door that covers the rotary stabilizer. Then make a test run. See if the problem goes away. I find it difficult to believe just the bearings at this point, because you have several machines doing the same thing. If someone used WD-40 on the shaft and bearings of your lateral sound guide roller, I'll bet that is what could be causing your whole problem. The whole thing might be gummed up. If that be the case, the only way I know of is to remove, dismantle, abd clean the units. It may be necessary to replace the small shaft bearings, as well as the cushion roller itself. WD-40 probably struck again.....
You say your scanner shaft is "tight". What do you mean by that? Is it hard to turn? If it is, you found the problem. It should turn very freely.
I hate those hump-back SH-1004's. POS! They don't even "fit themselves". 
Posted by Dave Williams (Member # 299) on 09-21-2001, 05:58 AM:
The drum turns freely, but it stops abrupbtly, and during its turn it is feels as if there is too much friction.I have an old set of bearings that are all gummed up. I sat them in degreaser for an hour and now they turn like champs.
What oil should I soak them in before installing them?
Dave
Posted by Aaron Sisemore (Member # 145) on 09-21-2001, 11:25 AM:
You destroyed the bearings by soaking them in degreaser, if they are the 'sealed' type. Get new ones. DO NOT use those bearings.Aaron
Posted by Paul G. Thompson (Member # 655) on 09-21-2001, 03:28 PM:
Aaron is correct. If they are not sealed bearings, Just a little motor oil will do - for now. I used vasoline on them (very sparingly) from time to time and it seemed to have favorable results, but there may be other things out there that are better than that.
It would by best to replace the bearings. They are cheap, and generic. Just get the bearing number off the bearing, and even some automotive parts houses can cross them for you. They run about 6 bucks a pop.
Posted by Dave Williams (Member # 299) on 09-22-2001, 02:39 AM:
I'm not a complete idiot. Of course they are not sealed bearings! I soaked them in some 10w non detergent oil and installed them. The sound warble is gone. I had a sneaky suspicion this was going to be the problem, but the only dumb question is the one not asked. I am already getting a whole new set of bearings for all my projectors. Thanks for all the help guys.
Wait till my next problem.. its a doozy..
Dave
Posted by Jerry D. Cox (Member # 701) on 09-24-2001, 02:02 PM:
Your pad roler has A flat spot on it,When you are not going to run it for A day or so you should open it,So the roler will not get A flat spot on it from your sonnd drum, This will make it bounce when you are running film an it will have A wobal sound,I had the same thing to happen one time you will have to put new pad rolers on to fix it it will not take but A little time to do this.
Posted by Rick Long (Member # 213) on 09-24-2001, 05:23 PM:
Jerry is right, the old Simplex sound-head manuals recommended leaving the sound-drum latteral guide rollers open when not in use. Because this was not done in a lot of cases, I spent a lot of time replacing the G-1985 felts and P-2360 bearings. Similarly in high-end turntables (showing my age here), it was often recommended that the turntable idler pulley be left in a "neutral" position to prevent flat spots.
Posted by Darryl Spicer (Member # 711) on 09-24-2001, 05:47 PM:
those rubber preasure damper rollers can also develop cracks in them and if they get big enough or a piece falls out they will cause the film to bounce.....I recomend leaving every thing open at night.....
Posted by Mark Gulbrandsen (Member # 72) on 09-24-2001, 07:29 PM:
So Dave,
How did you do a proper re-alignment on that soundhead without any test gear?
Mark @ GTS
Posted by Dave Williams (Member # 299) on 09-25-2001, 02:27 AM:
We actually do leave everything open and undone as it were at night. We recently replaced all the pad rollers, but all of the bearings on the drums are shot. I am planning on replaceing them all sometime this next week or two, as time allows.I am pretty sure I didnt get a good allignment actually. Or maybe I did. It was all by ear. You know we are too damn cheap to use equipment, or testing, or people, or money. All I know is that is sounded like hell with or without the warble, and at this point its presentable.
And speaking of cheapness, I did talk to the so called people about you know what... I got the same answer you did, just a run around and red tape. I would send guido. They werent interested in talking to me about it, they seemed rather put off that I would care. Personally I agree with you that I am somewhat crazy for continiuing here, I need therapy. Please god help me. Maybe I just like and impossible challenge. Someone tells me I cant do it and then I do it. Or break it. Mostly its a fifty fifty split, just like praying to god and the like. What the hell was I talking about anyway.
Dave