This is topic Strong Platter Motors in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Joe Redifer (Member # 3) on 10-01-2002, 09:01 PM:
I have a brand new Strong motor that is showing visible sparks when I am loading film at about 40% speed (according to the dial on the Strong MUT). The sparks aren't flying, but they are visible. Is this something I should be worried about? Or will the motor eventually "wear in" and stop this?
Posted by Richard Hamilton (Member # 321) on 10-01-2002, 09:33 PM:
Do you have electric or natural gas heating? I would be worried about sparking an explosion....unless you are using a "Matthew Bailey" recycling energy system. Then an explosion would power a whole neighborhood!!!Rick
Posted by Rick Long (Member # 213) on 10-01-2002, 09:48 PM:
I think, that once the brushes "form" their shape to the commutator, everything should be fine. You can start this yourself with some fine emery cloth, or sandpaper, but it is a really messy job, and not recommended. Time cures all.Still, best to lay off those nitrate film-festivals for awhile.
Posted by Wes Hughes (Member # 981) on 10-01-2002, 09:51 PM:
Strongs have brushmotors...they normally spark a bit when running. It shouldn't spark a tremendous amount, but a little sparking is normal in that type of motor. They will get better as the brushes seat.Having gas heating would make no danger. If ANY gas is escaping into the occupied space then you a malfunctioning furnace. It would take quite a noticible amount of gas buildup to cause an explosion.
Posted by Paul G. Thompson (Member # 655) on 10-01-2002, 10:23 PM:
I agree with Rick and Wes. Don't worry too much about it. The brushes will eventually wear in. However, if the motor sounds kind of funky, it may be worth looking into a replacement.
Posted by Joe Redifer (Member # 3) on 10-01-2002, 10:38 PM:
The motor doesn't make any abnormal sounds, but I did forget to mention that the sparks were accompanied by an odor. It smells like a motor burning. It is not a strong odor (pun intended) but it is there. I assume this is just part of the deal and it'll go away as well.
Posted by Paul G. Thompson (Member # 655) on 10-01-2002, 10:55 PM:
Joe, that is probably Ozone you smell. Pull the "can" off the motor and inspect the communtator and brushes. Your description sounds like the motor is having a problem of some sort. Maybe replacement motor is in order.
Posted by Mark Gulbrandsen (Member # 72) on 10-02-2002, 12:01 AM:
Hello Joe....Whadda Ya know,
Its best to let the motor brushes run in at about 30% of rated voltage for several hours. Then increase the voltage going to the motor after that time to help them seat in properly. Failure to do so could burn the commutator and possibly ruin it. Its possible that this motor snuck through this run in stage at the plant that makes them. Now for the commercial.........
At CLACO we rebuild all platter motors instead of replacing them. The only thing that will total a motor is a shorted armature or field winding. These could be rewound, but the cost is out of sight. Its a simple job to turn down and polish the commutator on a lathe and then check the armature for shorts and press new bearings on. When I do this I also use 600 grit paper against the armature and get the new brushes to this "cut" diameter so they seat in quicker. Only takes about 45 min to do one no matter which brand. We always run in the motors for several hours after the rebuild. Did 4 AW-3 motors this afternoon, and have more to do tommrrow. Will post some pics here of the operation.
BTW: What is a "Strong" odor? Is it the scent of a chicken cooking in the Super 80 grill?
Mark @ CLACO www.clacoequipment.com
Posted by Wes Hughes (Member # 981) on 10-02-2002, 12:28 AM:
the odor will go away when the brushes are seated a little better. you may smell it a little if you run the motor at full speed with a heavy load applied anytime though.
Posted by Daryl C. W. O'Shea (Member # 1303) on 10-02-2002, 12:39 AM:
I had a vaccuum cleaner that sparked for awhile when new.
After awhile the sparks went away.If you had a gas leak in the booth I'd let the auto-start ignite the bulb while I wasn't in the booth.
And why would anyone run a platter deck at full speed on the MUT?
Posted by Paul G. Thompson (Member # 655) on 10-02-2002, 12:41 AM:
Maybe my nose is gettin' bad....but I never smelled ozone emissions with those motors, even under heavy load when they were new. Joe, if all of your motors smell the same way under similar circumstances, then wait for the brushes to seat. Chances are, it'll take care of itself just like Wes suggests.
If it is just one motor that is causing concern, I would not trust that motor any more than the man in the moon.
Posted by Paul G. Thompson (Member # 655) on 10-02-2002, 12:43 AM:
Daryl, I do. But, safety first! 
However, I would never recommend that unless the operator knows exactly what they are doing, and how and when to ramp-up and retard the control without creating a personnel safety hazard and causing damage to the film.
Just like running a printing press in the newspaper facilities....they bring the presses up to speed (sometimes to 15,000 copies per hour at full speed, which calculates 250 copies per minute, or 4.1 copies per second.)
If the press operator misjudges in "bringing it up" or "bringing it down" ... well, he will definately have a very bad day that will cause him/her to head for the bar and get smashed.
Posted by Daryl C. W. O'Shea (Member # 1303) on 10-02-2002, 12:49 AM:
I often do too with only a reel or two on the deck, but with a whole feature on the deck? I find that the tension is too high.edit: If I remember right, you have it setup to go straight from the shipping reel to the deck without the stupid rollers inbetween. I can see that working. I wish I had the same.
edit again: I've done press runs, you have to rethread the whole thing when you snap the paper before you're allowed to head for the bar.
Posted by Paul G. Thompson (Member # 655) on 10-02-2002, 12:59 AM:
Daryl, one hand on the throttle, and one on the brake. In the meantime, watch for signs of over-speed, and watch for platter harmonic vibrations. Keep an eye on your butt, and keep an eye on the center ring. Listen to the equipment's performance, and use gut instinct. NEVER run at 100% on the last two reels you are pulling off. The resistance in the wind of the outriggers can provide enough back-tension to actually yank the center ring free of their holes.
Posted by Daryl C. W. O'Shea (Member # 1303) on 10-02-2002, 01:01 AM:
I was refering to loading a deck. I agree, breaking down the last few reels at a high speed could be hazardous to your health (and the film).
Posted by Paul G. Thompson (Member # 655) on 10-02-2002, 01:01 AM:
You are right on that one about heading to the bar.

Jeeze, we are doing this faster than I can keep up with...
I never worry too much about running at 100% on make-up. I supply a little back tension to keep things from whipping. Those felt pads in most of the MUTs seem to leave alot to be desired.....
But the key is still, bring it up gradually - just like a printing press so the film is not being strangled.
Posted by Joe Redifer (Member # 3) on 10-02-2002, 01:03 AM:
Well since this thing is under warranty for a year, I'll give it a few more weeks. In the meantime, I'll go ahead and turn the natural gas blower back on and put the bucket full of wet rags soaked in gasoline back under the motor. Thanks!
Posted by Daryl C. W. O'Shea (Member # 1303) on 10-02-2002, 01:05 AM:
Watch out for FujiFilm, it might spark and kill you! 
By the way, I've had a gas leak in a booth... it's no fun when the guy from the gas company is too interested in the projection equipment to fix the leak.
Posted by Paul G. Thompson (Member # 655) on 10-02-2002, 01:10 AM:
But Joe, it might go
Then the warrenty is void...
Posted by Wes Hughes (Member # 981) on 10-02-2002, 02:02 PM:
I think that anytime you have a tensioning device (as Strong MUTs have) you should use it. When I am building or breaking a programme I will run things very fast...as long as the tension roller doesn't bottom out (and the hub stays seated, and the whole stack doesn't wobble) i'll keep the speed up. I don't allow my other operators to run at full speed however 
Question: do any of you have MUTs with plastic ball bearing races? They suck on the MUTs, but are fine (although noisy) on the slower platter stack rollers. Order rollers with sealed ball bearings.
Posted by Mark Gulbrandsen (Member # 72) on 10-02-2002, 02:05 PM:
All new MUT's should be comming in with the metal bearings in the rollers these days. Those plastic rollers were a disaster!
Mark @ CLACO
Posted by Rick Long (Member # 213) on 09-18-2003, 11:24 PM:
Brining this one back with a question.
How often (in hours, if possible) should one expect new brushes on a Strong platter motor to last? I know that, in most cases, the top and centre decks are used much more often than the bottom decks, so these would obviously be the first to wear.
In the good old days, the union projectionists used to take care of this task for us. I used to notice them doing it and thot "Jeeze, that looks like a dirty job" Well, now it is MY dirty job.
P.S. What does the number "19" or "61" if you hold it the other way, on the brush indicate, the hardness of the carbon?