Film-Tech Forum ARCHIVE: Film Take-Up mechanical clutch problems on an FP20

This is topic Film Take-Up mechanical clutch problems on an FP20 in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Ian Griggs (Member # 9542) on 10-15-2016, 12:03 AM:

Now we've got the threading issue out of the way (thanks, Steve and others), can anyone help with the set-up of the mechanical take up clutch?
My machine would never have run spools, so the feed clutch and take up clutch would be virgin as it were.
As per the manual, I took the disc out, but not having any of the oil they specified, I washed it in kerosene then dried and put it back. But no matter where I set it(tight, loose, middling) I still can't get the film to take up smoothly without loose loops forming.
After a while (and a bit of help by me turning the spool), it comes good.
Hoping someone knows the exact trick with these.
My old 1940s machines never had this trouble! Many thanks, all.

Posted by Dave Macaulay (Member # 813) on 10-15-2016, 06:57 AM:

What diameter reel hubs do you use? That is a large sprocket, maybe it expects a lafge hub... measure free running rpm and see what minimum diameter it needs for 90 ft/sec.

Posted by Steve McAndrew (Member # 8865) on 10-15-2016, 07:16 AM:

Hi

I had the same problem with my FP20 when I was using 2000ft reels. Using a reel with a large hub solves this problem.

Posted by Steve Guttag (Member # 268) on 10-15-2016, 01:38 PM:

That sprocket should handle 5" hubs but it will NOT handle 4" shippers or cores.

Kinoton recommends "Cardan" oil which is a thick viscous stuff that pours like honey. Honestly, it feels like STP.

If you go that route, it is not unusual to have to press it out a bit and that after you set clutch tension (just strong enough to turn a full reel without bouncing)..that within a week's normal usage to have to readjust (increase) as some of the oil will have seeped out (pressed out).

Posted by Ian Griggs (Member # 9542) on 10-15-2016, 09:30 PM:

That's interesting thanks guys! And Steve, that's good too - this is why after a little while, it comes good as the diameter has increased with film.

Posted by Steve McAndrew (Member # 8865) on 10-16-2016, 01:24 AM:

I had a quick Google for Cardan Oil, don't get many results here in the UK. Do we think that SAE90 Gearbox oil is similar stuff?

While on the subject of making FP20s work again, can anyone advise on the part numbers of the lens turret belts and where I might get them?

Thanks

Posted by Steve Guttag (Member # 268) on 10-16-2016, 10:36 AM:

It is even thicker. It is on the order of SAE 140 weight.

As for belts and things. Have you tried contacting Kinoton Digital Solutions? They are still supplying parts.

Posted by Gordon McLeod (Member # 33) on 10-16-2016, 06:19 PM:

i use the SAE90 outboard gear oil that also is motiograph intermitent oil in the fp20's i still look after

Posted by Steve McAndrew (Member # 8865) on 10-17-2016, 03:08 AM:

Do do you just soak the felt discs in the oil?

Posted by Ian Griggs (Member # 9542) on 10-17-2016, 03:15 AM:

From the FP30E Manual:

6.4.10 Changing and Lubricating the Felt Disks of the Mechanical Friction Drives
• Remove the knurled nut, spring,
friction plate and the felt disk on the
friction shaft (arrow).
• Once in a year the felt disk should
be put in a Cardan oil bath. If the felt
disk is worn (surface is hardened) it
has to be changed and oiled.
• Mount the friction again.

Posted by Simon Wyss (Member # 6218) on 10-17-2016, 04:00 AM:

Once you have lubricated that felt pad with grease or heavy oil, it can be run dry as well under the condition that the faces in contact with the felt are polished smooth, there remains the geometric problem of large portions.

It’s almost impossible to adjust a friction for 6000-ft reels so that you have satisfactory winding and no film damage. At the beginning the strong torque will almost rip the film over the sprocket drum and towards the end it will not suffice when set lighter. That’s why motor drives were introduced.

For 2000-ft reels it can be done comparatively easily. Make sure you use 5-inch hub reels throughout.

One last technical detail: Use sprocket drums with wide teeth for ISO 491 BH*, KS** or DH*** type perforation. CinemaScope toothing is only advised for ISO 491 AC**** type perforation. We have compatibility to some extent but the holes and teeth are narrower and what counts also, the spacing between the two hole/teeth rows is different.
____________________

*Bell & Howell, rounded flanks, straight top and bottom sides
**Kodak Standard, straight sides, rounded corners
***Dubray-Howell, straight sides, rounded corners
****American CinemaScope, straight sides, rounded corners

Posted by Rob J. Buskop (Member # 3338) on 10-17-2016, 11:51 AM:

There are two factors that, if adhered to, will let the FP-20 start very nicely with a standard 6000 ft. reel.
O.K. The matter of the friction of the take-up spool: The felt ring has indeed to be treated with "cardan"oil. This is a European term and seems to be misunderstood in the U.S. It is the oil that you put in the differential of your car. It's diff oil, that has that peculiar strong smell. Any garage can supply you with a bit if you bring a small jar!
The second thing to consider is the time factor for the motor to rev up. Philips has installed a number of electrolytic capacitors, often found mounted in the door, that allows you to
alter the capacitance of the starter circuit in the motor. The lower the capacitance, the slower the start. You can get it just right for a 6000 ft. reel. With the friction correctly adjusted and the motor set up for a somewhat soft start all will be perfect!
To conclude this, I'll give away a secret to make your FP-20 run more quietly.... I suppose it's not been modified and still has the original motor with the V-belt drive, right? Well, get yourself a good quality silicon rubber O-ring. A fat one, with
an approximate thickness of 6 millimeter, to replace the belt.
The result will surprise you! The elasticity of the O-ring absorbs a good part of the intermittent shock-load, which does'nt
happen with the normal V-belt. As said: The result will amaze you!
Finally: The cross mechanism. It needs Shell Tellus 37. This is a low viscosity, ATF-like oil. That's what is prescribed.
Succes!
Rob J. Buskop.

Posted by Mitchell Dvoskin (Member # 751) on 10-17-2016, 02:19 PM:

It needs Shell Tellus 37 no longer exists. Is there a current equivalent?

Posted by Steve McAndrew (Member # 8865) on 10-17-2016, 03:38 PM:

You can get this in the UK...

http://www.ebay.co.uk/itm/Shell-Tellus-37-Equivalent-Hydraulic-Oil-5L-ISO-37-Westway-Lubricants-/111729963522?hash=item1a039ff202:g:JuAAAOSwX~dWls0r

Posted by Rob J. Buskop (Member # 3338) on 10-18-2016, 07:20 AM:

Here's another supplier that seems to sell a substitute in 1 litre containers.
http://www.alexoil.co.uk/shell-pre-iso-iso-lubron-oil-reference-guide_c123.aspx
It'll be a useful equivalent.

Posted by Ian Griggs (Member # 9542) on 10-19-2016, 11:46 PM:

Thank you gents. All excellent info!
Looks like here in oz it's down to Supa Cheap Autos for a drop of "Diff Oil" for the clutch disc!
One thing I did try which works straight away, is the take up hub diameter. Using a 6000ft spool for take up (irrespective of what is the feed spool), it takes up nicely from the start with no loose rolls. That's why when taking up on anything smaller, it came good after the hub diameter increased with a few minutes of film. Cheers and happy Kinotoning?

Posted by Steve Guttag (Member # 268) on 10-20-2016, 01:32 AM:

For "6000" foot reels, I've generally liked using 7-inch hubs (and 25-inch flanges). Getting that hub larger goes a long way to smoothing out the take up at start ups. Ideally though, you'd like to keep the hub to flange ratio to 3:1 or less. So technically, for a 24" reel, the hub should be 8" but then you won't get 6000-feet.