Film-Tech Forum ARCHIVE: AW3 problem with drive roller

This is topic AW3 problem with drive roller in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=006762

Posted by Brad Allen (Member # 470) on 12-03-2004, 12:08 PM:

Two AW-3 platters, and out of the six decks, there is one that is having a problem with the roller that drives the platter.
It "sheds" the rubber off the roller onto the drive edge of the platter. I just replaced this roller about 3 months ago for that reason, and the new one is doing the same thing. It takes some effort to clean the rubber off the platter edge, it is sort of gummy. Have to keep it cleaned off or it makes the platter run rough.

I've checked the tension on this motor, and it's the same as the other five that are not having any problems. The tension couldn't be much lighter, it wouldn't drive the platter properly.

Does Christie have a problem with the rubber compound being used to make these rollers? Any other suggestions on what to check?

Posted by Dominic Espinosa (Member # 2122) on 12-03-2004, 12:24 PM:

Our #4 house has gone through 3 of those over the last few months. It's a pain in the ass and I have to tell you, acetone can really get to you, even with a mask on.
The problem is a bunch of crappy made drive tires from Christie.
A few other people on the forums have had similar problems with them.
Christie Platter Motor Drive Wheels ?

Posted by Scott Norwood (Member # 30) on 12-03-2004, 01:45 PM:

As mentioned above, some rollers just do that. You can tell that they are about to disintegrate when they start to ooze around the metal ring in the center. Check yours periodically and replace the ones which are oozing.

The newer white rollers from Christie and the black rollers (from Wolk?) don't do this and are fine. There are also older rollers which are great and which do not ooze or develop flat spots. I haven't noticed any significant difference between the white and black rollers, but others may have a different opinion on this.

Posted by Michael Rourke (Member # 1142) on 12-03-2004, 02:37 PM:

Yeah the black wheels from Wolk work great, no problems.

Incidentally, Film Guard will take the cream colored roller gunk off the platter hub and is easier on the nose and brain than Acetone.

Posted by Ever Gonzalez (Member # 2794) on 12-03-2004, 06:15 PM:

Jesus, and I thought we were the only ones with that problem!

Posted by Randy Stankey (Member # 64) on 12-03-2004, 10:51 PM:

quote: Dominic Espinosa
acetone can really get to you, even with a mask on.

Dominic,

Unless you are wearing a SCBA, an air-line mask or at least a respirator specifically approved for use against volatile substances, your average face mask/respirator is useless against acetone fumes.

In fact, if you aren't wearing a respirator specifically designed for use against volatile substances you are probably making the problem WORSE by concentrating the fumes inside the cavity of your mask.

The only way to guard against acetone fumes is to make sure there is enough fresh air (open windows & doors) and to limit the amount of exposure by keeping keeping the container capped unless actually in use.

You really ought not to have acetone in your booth unless absolutely necessary. FilmGuard should do the trick.

PS: I thought Christie solved that problem YEARS ago!?

Posted by Mark Gulbrandsen (Member # 72) on 12-04-2004, 09:13 AM:

quote:
PS: I thought Christie solved that problem YEARS ago!?

Actually the original rollers were just fine then they went to obviously cheaper sources and the problems developed. Even the latest rollers have problems. We only use the black Wolk rollers and have never had any problems at all with them. The rubber compound they use is excellent! Hopefully Wolk won't change them or cheapen them up or the population of AW-3's out there are all in trouble.

Mark

Posted by Dominic Espinosa (Member # 2122) on 12-04-2004, 01:08 PM:

Randy,
I do use the acetone in a well ventilated area. I've found that FilmGuard didn't really do much for me getting that goop off. Next time I'll try something a little less...fumish.

Posted by Brad Allen (Member # 470) on 12-06-2004, 10:45 AM:

Thanks all. I'll order the Wolk roller.

Posted by Randy Stankey (Member # 64) on 12-06-2004, 11:58 AM:

[sarcasm] Acetone is one of those chemicals that can be a lot of "fun". [/sarcasm]

When I was in Tech School we got put on a work detail and had to repaint all the doors in the classroom area. It was oil based paint. All of the doors had glass windows in them. The teacher instructed us that there was to be NO paint on the windows when we were done. One of the kids got an old Coke bottle, filled it up with acetone and used an old rag to daub the paint off the windows after he was done painting. (The rest of use just used masking tape. [Wink]

)

About a 1/2 hour later, this kid was sitting on a stool, cleaning paint off the window when he abruptly stood up. His face went ghost white and his knees buckled out from under him. Nobody knew what happened to him until the teacher picked up the acetone-soaked rag and took a whiff.

I still remember the look on the teacher's face... "Oh! For Crist's Sake!", he said, "Take him outside and get him some air!" Then he picked up the Coke bottle and rag, held it up and said, "Let this be a lesson to you!" He promptly disposed of the rag and bottle.

I imagine he was destroying the evidence in case the school administration and/or the safety authorities got wind of the fact that he "let" us use acetone indoors. The fact is, he didn't LET us use it. We used it without permission but questions would have been asked and people would have been called onto the carpet, none the less.

THAT's the reason I said you ought not to have acetone in the booth... I've seen the consequences.

Posted by John Pytlak (Member # 331) on 12-06-2004, 12:20 PM:

Acetone is also VERY flammable and the vapors are explosive. [Eek!]

http://www.sefsc.noaa.gov/HTMLdocs/Acetone.htm

http://hillbrothers.com/msds/pdf/acetone.pdf

Posted by Randy Stankey (Member # 64) on 12-06-2004, 07:56 PM:

One other thing. Acetone smells kinda' good at first. It's sort of sweet. You don't mind the smell of acetone so you don't notice that it's making you sick. Then, all of a sudden, WHAM! It sneaks up on you! You're lying on your ass and you don't know what hit you!

That's exactly what the kid said when he came back inside afterward.

Posted by Dominic Espinosa (Member # 2122) on 12-09-2004, 12:34 PM:

That's wierd. I hate the smell of every chemical I've ever come in contact with. This includes gas, acetone, alchohol, and windex.
I never could understand people who "huff" spray paint.

Posted by Steve Guttag (Member # 268) on 12-12-2004, 05:49 PM:

Acetone is indeed flammable. Many use MEK instead. It is quite similar, chemically. It also has a lower flash point.

Steve

Posted by John Pytlak (Member # 331) on 12-13-2004, 08:00 AM:

Methyl Ethyl Ketone (MEK) has quite a few hazards too:

quote:
Flash Point: 25.0F,-3.9C
Flash Point Method: TCC
Lower Explosive Limit: 1.8
Upper Explosive Limit: 11.5
...

Health Haz Acute And Chronic: EYES: SEVERLY IRRITATING. IF NOT REMOVED
PROMPTLY, MAY RESULT IN PERMANENT DAMAGE. SKIN: PROLONGED CONTACT MAY
IRRITATE AND CAUSE DERMITITIS. INHALATION: VAPORS ARE IRRITATING TO
RESPIRATORY TRACT AND MAY AFFECT THE CNS. INGESTION: LIQUID ASPIRATED INTO
THE RESPIRATORY SYSTEM DURING INGESTION MAY CAUSE PULMONARY EDEMA.

http://www.2spi.com/catalog/msds/msds02850.html

Posted by Juan Urias (Member # 1990) on 12-14-2004, 02:52 PM:

quote mark wrote:
_____________________________________________________
Hopefully Wolk won't change them or cheapen them up.
_____________________________________________________

Thank You all for the good feed-back on the rollers.
We will not go the cheap way in the future to save money on production.we will keep making them out of the same material.
like the saying goes "why fix it,if it ain't broke"......JUAN