Film-Tech Forum ARCHIVE: AW-3 platter thrust bearing

This is topic AW-3 platter thrust bearing - clean or replace in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Justin Hamaker (Member # 2165) on 11-01-2009, 07:21 PM:

I have a platter deck which is not turning smoothly. When I removed the platter, I found the thrust bearing is kind of gummed up and does not turn freely. What I'm wondering is if these can or should be cleaned or if they should just be replaced? If they are cleaned, should they be lubricated in any way?

Posted by Ian Parfrey (Member # 5122) on 11-01-2009, 08:10 PM:

Justin.

Bearings aren't all that expensive and if that particular bearing is still available, I would just replace the thing, even to the point of doing all 3 decks. If it is NOT available, then a flush and relube may be in order. That will depend on the condition of the bearing in the first instance. If it has worn flat spots on the balls/rollers then its destined for the bin in any case and an alternate bearing will have to be sourced.

Cheers
Ian

Posted by Mark Gulbrandsen (Member # 72) on 11-01-2009, 09:56 PM:

They can be cleaned but need to soak over night...carb cleaner works well but consider it's flammability when using it!! Also, do not get the three decks thrust washers mixed up! They may be different and if you do get them mixed up it'll require a sorting out of platter heights vs. washer thickness. I believe that Christie used three different thicknesses of washers over the years so there could be several possibilities there. Re-lube the bearings with Mobil-1 synthetic wheel bearing grease. This is probably the nbest grease you can easily get off the shelf for this purpose ( Available at any auto parts store worth their spit!). Also clean the bronze bushings at the topside of each deck's axel hole and clean the axel as well. Re-coat it all with the Mobil-1 grease and re-assemble. Wipe off any that may ooze out so it doesn't get on any film. I also suggest a re-timming of the platters after doing the clean and re-lube as they may run a bit faster then they did. The drag that was there will now be gone...

Mark

Posted by John Walsh (Member # 168) on 11-02-2009, 06:13 AM:

Agreed about the greasing, but be wary of adjusting the timing; I've seen too many AW3's running 'OK until someone tries to 'make it better.' And I don't mean inexperienced people adjusting, I mean with all the parts that have gone obsolete in the last 10 years, they don't work together to well anymore and you might not get it back to running normal.

Posted by Jim Cassedy (Member # 4115) on 11-02-2009, 10:57 AM:

quote: John Walsh
I've seen too many AW3's running 'OK until someone tries to 'make it better

A very timely comment! I had a complete platter implosion
at one location just last week because the house tech there
decided to make a few 'improvements' overnight on two
different platter systems.

Unfortunately he didn't fully test the system when he was
through. It's one thing to give a quick check with a couple
of trailers, and quite another thing when you load the deck
down with a 7reel feature.

The following day was a nightmare! Brain-wraps and alomst
thrown prints during the first show. I spent the entire
2nd show running across the booth between the 2 platter
systems, having to slow one down and speed the other one
up by hand the entire show.

I can laugh about it now, but at the time it was anything
but funny.

It took almost 2 days for me to get everything running
smoothly again. (No, it doesn't take me two days to time
a platter- but these particular decks have had so many
"improvements" and modifications done to them over the
years that it's pretty much impossible to do any type
of standard 'by the book' timimg proceedure on them.
And each deck is different! It's either funny or
frightening, depending on your point of view!)

Posted by Brad Miller (Member # 2) on 11-02-2009, 01:54 PM:

Oh boy, been there done that in the past. That is actually the reason I decided years ago to create a platter safety ring, because there were too many times somebody (tech or otherwise) would try and do a good thing by jacking with the timing, and then the prints ended up all over the floor. [Mad]

That is also why I always felt it was a joke when someone would be demo'ing a platter at a trade show with less than an hour's worth of film on it. You can set the timing damn near anywhere and the first hour will run just fine!

Posted by Mark Gulbrandsen (Member # 72) on 11-03-2009, 09:18 AM:

quote: John Walsh
I mean with all the parts that have gone obsolete in the last 10 years, they don't work together to well anymore and you might not get it back to running normal

What parts that have gone obsolete? Oh yea... the old style black rollers and non-removable pay out heads. You still have your choice of the old detector assys. or the new style all of which should in theory be changed out at the same time. Motors are basically the same, drive wheels are available from two sources and either works very well. Motor drive cards have also been brought up to date and are as reliable as the old ones and they are compatable. Push button deck make up switch has been updated because they stopped making the old one, new one is very easy to install. The AW-3 is the easiest of all the platters out there to maintain and keep operating correctly!!

Now John should we discuss the Neutronic Platter... which drive board revision are you on with that platter now??? Or has Neumade quit making those boards? Remember those drive board revisions where the ceramic resistors got so hot they actually melted?

I disagree on not re-timming the platter. If you have an accurate meter and platter tachometer then it can be done accurately and safely. But of course anyone that wants to guess at adjusting it is in for some possible trouble. Test running some film after re-timming is mandatory no matter what.

Mark

Posted by Justin Hamaker (Member # 2165) on 11-03-2009, 03:24 PM:

I do know how to time a platter using a multimeter and counting revolutions. Other than being time consuming, it's not a problem.

Posted by Brad Miller (Member # 2) on 11-03-2009, 03:58 PM:

Make sure to get the resistance set properly if you are using the red or green leds before you time!!!

If you have the infared leds, well, I feel your pain. You may want to purchase some of these.

(Christie makes great products, but they all know how much I F'ing detest the print-slinging infared led crap.)