Unstable frame kinoton fp30

[Javier de Blas]

Hello everyone. I have a problem with my kinoton fp30. Polyester prints are a bit unstable vertically, acetate prints look alright. I'm worried it could be a register pin problem. If you guys can tell me things I can check to find what's the problem it would be great. Thanks in advance.
Also, let me tell you how it goes. When I start giving more pressure to the film the shakiness reduces as it usually does but it comes to a point where is still a bit shaky and no matter how much more pressure i give it, it does not fix it.

[Stefan Scholz]

Skies and pressure plate still ok or worn out? Ceramic rollers clean and without grooves? Loops in right sizes? Intermittent sprocket still good?

[Tj Hopland]

I don't know the models that well or if there should be some letters on the end of that but does this have a coupler? If so that's where I would be looking.

[Josh Jones]

I don't know the models that well or if there should be some letters on the end of that but does this have a coupler? If so that's where I would be looking.

Yup, a common wear item on the Kinotons.

[Adrian Avram]

Javier did not specified what type of FP30 projector it has, there are variants FP30A, FP30D and FP30E, which are very different when it comes to intermittent movement.
If we are talking about the pure mechanical one, FP30A, then indeed the main culprit of up/ down shakeiness is a worn out coupling bushing, seen below joining the drive shaft and intemittent sprocket shaft.

Coupling bushing.png

[Gordon McLeod]

It is probably not the coupler as acetate prints run ok most likely gate tension issue

[Jim Cassedy]

<edited> most likely gate tension issue

Before you panic too much and start pulling things apart, I had a stability problem with
a polyester print a few months ago, and it turned out to be a problem with the print, and
not with the projector. We have a 2-proj change-over system, and although the problem
showed up on both projectors, it was a little worse on one than on the other. Setting the
gate tension on the Century JJ's to maximum fixed it on the right-side projector, although
I still had some jitter on my left side machine.

BUT THIS FIXED IT!
JitterStopper.jpg

I've run more than a dozen different 35mm features since then, (without the
rubber band) and haven't had problems. It was just that one stupid polyester print.
I was actually surprised the rubber band didn't melt, since the gate & trap, even though
water cooled, still gets pretty hot with our 4.5k Xenons, but it survived all week OK.

[Julian Antos]

It’s possible the omega spring, which applies gate tension, is wearing out and needs to be replaced. Ideally gate tension would be at no more than 2/3 for polyester films.

[Gordon McLeod]

Remember than polyester prints are thinner than acetate so the gate tension must be increased

[Christian Anner]

If the skates and the pressure plate is new and its adjusted in the right way, the pressure gauge has to be within the range of total minus ( - ) and medium. In the Lab were i once worked we had all Kinotons adjusted that way and there was no adjusting between acetate and polyester necessary. To find the right adjustment could be a PITA but when its finally done right, the machine, even with the geneva movement is not much louder than a standard 16mm Projektor.

[Mark Gulbrandsen]

All good advice here, but I did not see anyone mention to determine if it's the coupler that has started to fail, or if it's a tension issue. Both can cause much the same thing.

[Gordon McLeod]

All good advice here, but I did not see anyone mention to determine if it's the coupler that has started to fail, or if it's a tension issue. Both can cause much the same thing.

If it was the coupler it would do it on acetate and ester prints which he says it does not

[Ryan Gallagher]

To check if it is a bad/shaky printing, remove the aperture plate and pan to where the sprockets are visible on screen, if they are stable but image is not definitely the print. Hard to do during a show of course!

[Javier de Blas]

Hello! Sorry for not taking a look at this in so long. It's been a crazy couple of months.
For starters, I took part of installing the first 70mm projector in Madrid in Spain since the 80s. And then projecting three times a day for a month and a half. I recorded a little video of the DP75 and the cinema if anyone is interested.

https://youtu.be/pkxaAr3XwJg?si=9tBR9aYGu9-GNVc_

And then I was kicked out of the photo lab where I used to have my kinoton. Which I'm currently in the process of installing in my house. I'll make a video when it's all finished and ready.

Now, answering your questions.

Skies and pressure plate still ok or worn out? Ceramic rollers clean and without grooves? Loops in right sizes? Intermittent sprocket still good?

The skies were a bit worn out, but I interchange them and they seem to be ok now, the pressure plate is fine. Even though, now that I'm doing a proper full maintenance. I think the height of it needs to be adjusted.
The rollers are clean and not worn out. Anyway, in the maintenance I'll take all out and do a more thorough cleaning of them.
Loops are right, that I know right, the classic two fingers top, one finger bottom.
The intermittent sprocket it's quite dirty and with very little visibility it has I don't know if the pins are fine or not. That's one the reasons where I would bet money the problem is. Again, I'll try to find a replacement and change it now in maintenance.

[Javier de Blas]

Javier did not specified what type of FP30 projector it has, there are variants FP30A, FP30D and FP30E, which are very different when it comes to intermittent movement.
If we are talking about the pure mechanical one, FP30A, then indeed the main culprit of up/ down shakeiness is a worn out coupling bushing, seen below joining the drive shaft and intemittent sprocket shaft.

Coupling bushing.png

It's an FP30D. I'm really afraid it could be the framing. Because I don't see an easy fix to that. Generally, I don't see how could I even get the piece of plastic that worms out connecting the intermittent sprocket and the geneva drive.