Film-Tech Forum ARCHIVE: Victoria 5

This is topic Victoria 5 - Smearing text? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Ron Davis (Member # 4124) on 01-10-2007, 05:41 PM:

I've been getting such great response from my other "Victoria 5" post, I figured I'd better strike while the iron was hot!

The same projector that is having the sound problems is also having a problem with text or any large area of white surrounded by dark areas. It looks like the text/area is smearing down.

We've had the problem fixed (or minimized) by someone adjusting the belts that pull the film thru. That person has since moved on after leaving me to carry on the legacy. I've looked at the sprockets and found some of the rollers marked with a red dot, and I'm sure that has to have something to do with the timing, which I'm HOPING is the culprit of the mystery smearing text.

Again, this site and the people on it have been a TREMENDOUS help and any insights are greatly appreciated!

Thanks again!!

Posted by Mike Blakesley (Member # 26) on 01-10-2007, 05:44 PM:

That's a phenomenon known as "travel ghosting" and is indeed a timing issue.

What's happening is, your shutter blades are slightly out of sync with your intermittent. You're seeing the film starting to move to the next frame (or coming to a stop from the previous frame) because the shutter is opening too soon (or too late).

There may be a "knob" on your projector head that will fix this problem with a simple twist.

{EDIT: To remove my wrong guess about the red dots.}

[ 01-11-2007, 12:29 PM: Message edited by: Mike Blakesley ]

Posted by Ken McFall (Member # 845) on 01-10-2007, 06:04 PM:

Hi guys,

the problem you describe is certainly travel ghost caused in the way Mike has described.

The red dots you see on the drive shafts for the intermittent and the shutter gear box are indeed to do with the shutter timing.

The top shutter red dot should be at 6 o'clock position and the bottom intermittent should be at 9 o'clock position with the belt at tension.

Provided the shtter was originally installed correctly and has not been altered the dots provide an easy way to change the timing belts and maintain proper shutter timing in relation to the intermittent.

If you look in the manual section you will find a vic 5 manual that explains how to change the timing belt and set the dots and tension correctly.

It is very important that you change BOTH timing belts at the very least twice a year, depending on operating hours. They are not expensive and with the cleaning of the pinions, gears and rollers that should take place at the same time will help your projector run smoother and quieter.

It's also very important that the rollers that are positioned to keep the belt in place DO NOT ride the belt. They are intended to stop the belt coming off the pinion NOT to hold the belt on. If these three rollers are pressing hard against the belts the projector will sound and run roughly, nosily and the belts will deteriorate very quickly. I usually set them so they barely touch the belts at all. Make sure all of the rollers are cleaned every time the belts are changed.

Spend a few hours reading the manual and giving the projectors a full service. It's not difficult and is an excellent investment of your time.

Posted by Richard Fowler (Member # 893) on 01-10-2007, 07:50 PM:

So one projector is the dog [Razz]

Ken is on the money regarding belts and timing. ALWAYS prior to removing belt check to see if the timing marks match on the shutter box and intermittent when you manually rotate the drive train....some rare instances a rebuilt box or intermittent is not properly referenced and you may need to put a new mark(s)...again, this is very rare. If your timing marks ( if properly marked ) are off by one tooth, timing smear is noticable. When replacing belts recheck that your timing marks did not drift when you tighten up on the idler arm for the inner belt. Your shutter box may have worn drive gears allowing for"ghosting". You can check for loose play by gently rocking the shutter shaft. The shutter, itself, has some slotted holes to allow some rotation of the blade to fine tune the timing; these sometimes become loose. The shutter box has a grease access cap which most people forget to add lubricate. Shutter box mechanical problems can creep into the sound reproduction.
Finally check for a hole in the shutter; the V-5 shutter can not take much heat abuse and in worst case situation, the air fins on the shutter will be "tapping" the housing.

Posted by Gordon McLeod (Member # 33) on 01-11-2007, 07:57 AM:

Also some people atempt to time the shutter setting the blade in the same position one would with a XL or Century
the manual is on this site in the manual section and one needs to follow it

Posted by Dave Macaulay (Member # 813) on 01-11-2007, 10:33 AM:

Definitely read the manual! The dots might be useful but on a V5 that's been worked on a lot they are usually meaningless - if you have had a shutter gearbox repaired or replaced it takes a bit more time and knowledge to put it in with the timing AND marks correct than to get the timing right but the marks wrong.
The shutter drive gearbox is the weak link in a V5, making sure they have grease is important. It's a pretty expensive thing to replace, too.
I would try to check the shutter timing visually before going further, that will let you see if a shutter blade is damaged too. If it's close, just move the timing belt one tooth in either direction then you may be good but if the timing gets worse move it 2 teeth the other direction. I can sit and think about which way is right for an hour and it's still 50-50 whether I'm right.

Posted by Gordon McLeod (Member # 33) on 01-11-2007, 11:55 AM:

I always make it a point to have the dots in the right place when I change a gear box as it is better for the next guy who has just a belt to change
the gear box is actually fairly robust if not abused
using a slow start ramp on an invertor has stopped almost all the replacement issues

Posted by Gustav Viem (Member # 3750) on 01-27-2007, 03:54 PM:

If the red dots on the drive shafts are in position and you still have the travel ghosting problem you also should check the guide rollers that the timing belt is running on and their ball bearings.
I had this problem on a few vic5 projectors. Some rollers and their ball bearings were so worn that the timing became wrong.! The distance between the drive shafts for the intermittent and the shutter gear box via the rollers had become slightly shorter. Changing the rollers and ball bearings fixed the problem.