Film-Tech Forum ARCHIVE: Kinoton FP23 Sprocket Hold Down Question

This is topic Kinoton FP23 Sprocket Hold Down Question in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Mitchell Dvoskin (Member # 751) on 05-12-2004, 07:50 PM:

Is there any easy way to increase the spring tension on the hold down over the bottom sprocket on an FP23 (same as FP20)? The reason I ask this is I run a lot of older prints, some of which have thick cement splices that probably have been there for decades. These thick overlapping cement splices sometimes jump off the bottom sprocket because the hold down is not holding down tight enough, causing the projector to lose it's lower loop. I have no problem with tape or lab splices.

Any suggestions would be appreciated.

/Mitchell

Posted by Gordon Bachlund (Member # 124) on 05-13-2004, 08:53 AM:

I have the same problem occasionally on my FP20s with prints that have shrunk. I believe the problem is exascerbated by the relatively large diameter sprocket, which is gentle on film but engages more sprocket holes than the smaller sprockets on most other machines.

I will look into this. Let's keep in touch. [Smile]

Posted by Larry Shaw (Member # 388) on 05-14-2004, 11:11 PM:

With one hand and either the special steel tool provided with new machines or a screwdriver, apply rotating force to the silver section of the sprocket pad pivot. With the other hand and a metric allen wrench, loosen the screw in the center of the pivot. Rotate the silver section to achieve the correct pressure. Tighten the screw.

This procedure is in the FP-23 manual.

Actually the correct fix here is to remake the bad splices; overtensioning is treating the symptom, not the disease.

Posted by Mark Gulbrandsen (Member # 72) on 05-14-2004, 11:57 PM:

"Actually the correct fix here is to remake the bad splices"
_________________________________________________________________

Really now Larry, do either of those guys faces say to you.... "lets cut out a frame or two of that nice I.B. release print film for sake of a messy splice"

I think in reality they'd both rather use rubber bands to hold the pad shut [Wink]

than loose a single frame of film.....

Mark

Posted by Dan Lyons (Member # 1454) on 05-15-2004, 02:45 AM:

quote: Mark Gulbrandsen
Really now Larry, do either of those guys faces say to you.... "lets cut out a frame or two of that nice I.B. release print film for sake of a messy splice"

I'm assuming the problems are coming from shrunken cement splices. Many times i've found you can just peel the splice apart , then do a tape splice over the overlapped film, which will put the sprocket holes back into proper registration, and no frames have to be cut. Just make sure your pad rollers are set so they can handle an overlapped tape splice, which it should since i know all of you have modified your splicers to do overlap cuts. [thumbsup]

These type of splices run perfectly thru a Century and a Pro 35, I'd think the Kinoton should be able to handle those also. [Wink]

Danny

Posted by Mitchell Dvoskin (Member # 751) on 05-17-2004, 07:52 AM:

Thank you Larry. I even found my special adjustment tool in my box of Kinoton "I don't know what it is, but I may need it someday" items.

One other question, in the manual, it describes setting the correct tension with a little spring scale gizmo. Where does one get one? Years ago, tiny hanging postal scales were sold everywhere, but not any more.

Thank you Mark, you understand.

/Mitchell

Posted by Richard Fowler (Member # 893) on 05-17-2004, 09:37 AM:

Amtek-Chatillon guages - model DDP series would be your choice; should be available from any major industrial supply - tool distributor. My 30 year old unit is still doing a fine job

Posted by Larry Shaw (Member # 388) on 05-18-2004, 12:57 PM:

Sometimes one can find cheap-o scales of this type at fishing supply places.

Posted by John Pytlak (Member # 331) on 05-18-2004, 01:08 PM:

Fish scales (the weighing kind):

http://www.bigskyfishing.com/Gear-Technique/spin_fishing/pages/fishing_scales0001.shtm

quote:
All of the fishing scales and fish measurement devices shown below are available through Cabela's. For pricing or additional information, simply click on any of the links.

http://www.tackletour.com/reviewberkleyscale.shtm

http://www.amazon.com/gp/browse.html/104-8390627-1917536?node=3409051&no=3408951&me=ATVPDKIKX0DER

SMPTE Recommended Practice RP106 specifies Film Tension

Posted by Richard Fowler (Member # 893) on 05-18-2004, 01:14 PM:

How many times do you have to wrap the barracudda around the reel hub to get an accurate torque measurement [Big Grin]

The scale I was mentioning allows for torque measurements on one end and pressure measurements ( such as gate pressure ) on the other [Cool]

Posted by Dan Lyons (Member # 1454) on 05-18-2004, 01:25 PM:

Here is what i use to measure takeup and reel arm tension.
spring scales I have the red, 1-20N version.
They work great, and you can't beat the price!

Danny

Posted by Richard Fowler (Member # 893) on 05-18-2004, 03:35 PM:

At that price they should be given out to techies like tweakers [Cool]

Posted by Brad Miller (Member # 2) on 05-18-2004, 04:31 PM:

Danny sent me one of those spring scales and it really does come in handy. Everyone run out and buy a couple! [thumbsup]

Posted by Mark Gulbrandsen (Member # 72) on 05-18-2004, 10:06 PM:

"Danny sent me one of those spring scales and it really does come in handy."
_________________________________________________________________

Well yes, now that you mention it, I do quite a few service calls that are near some really nice trophy trout streams in both Wyoming and Montana [Cool]

, simply wonderful . So yes, they might actually come in handy once in a while!!

Mark