Announcement

Collapse
No announcement yet.

Take Up Reel is lagging and film sometimes spill on the Floor...

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Take Up Reel is lagging and film sometimes spill on the Floor...

    Hello all, I am currently running reel to reel projection for two Century JJ 35mm/70mm Hybrid Projector's. One of the Projector's the take up reel is starting to lag and not picking up speed. The two discs at the other end of the arm are not locking together even with the pad in the middle. I cleaned the two discs with alcohol and working on replacing the pad, but will that solve the issue or is there something else causing the take up reel to lag? Much help and advice would be appreciated. Thanks

  • #2
    it sounds like you have kelmar arms or b&h instruments, there is a roll pin that engages the outer disc to the reel shaft, make sure it is properly seated in the slot in the metal disc, it is the two discs that squeeze the felt disc to provide the clutch to slip. most likely oil is your problem either on the belt or the drive pulley on the soundhead. make sure the take up belt is not too slack, it should be taught, if it is yellow or blue rounthane wipe any oil film off of it. you should be able to squeeze the belt almopst together midway with reasonable effort, otherwise it may be too tight also if too loose it will slack under start up. felt clutch discs should be lightly oiled with projector oil, otherwise they will polish up and not work well, if the belt is leather it must be taught, if the clutch is phenolic (plastic) or leather it should not be oiled and may need to be roughed up with a coarse file or rasp, you can also rough up he felt type discs. if your problem is with 6000ft reels, make sure you are using floating hubs and they are free turning on the reels. lastly, make sure the clutch is adjusted so you can stop an empty 2000ft reel at speed with one finger without belt slippage or if you have a hand held fish scale, you can attach it to a piece of film on the reel and there should be 6-8 oz of tension at start of 5" hub 2000ft reel, 10-12oz for 6000ft reels have fun!
    Last edited by John Eickhof; 01-17-2022, 05:33 PM.

    Comment


    • #3
      If it is a felt disk in the clutch it does need to be soaked in oil (as per the manufactures recomendation) also adjust the spring to ensure sufficient torque. Also is it a issue only at start up then maybe the slow start resisitor is incorrectly set

      Comment


      • #4
        I'm just curious. . . are you currently running 70mm?
        Specifically, reels 2 & 4 of "Licorice Pizza" on that projector?
        Those two reels are the heaviest I've come across in some time,
        and I had to tighten up the take-up clutch a bit more than usual to
        keep the take-up from stalling when running those two reels

        Comment


        • #5
          I have never soaked the pads in oil because I have found the oil just attracts dirt. I CLEAN and dry the pads and have had zero tension issues on payout and takeup.

          Comment


          • #6
            Every manufacturer of takeup clutch always recommended oiling the felt.If they are run dry they actually groove the aluminum disks

            Comment


            • #7
              Originally posted by Gordon McLeod View Post
              Every manufacturer of takeup clutch always recommended oiling the felt.If they are run dry they actually groove the aluminum disks
              Totally agree with Gordon. I always oiled the felt pad... the pad lasts longer too. The clutches are just 6061 Aluminum, so not particularly hard., and if you run them dry the aluminum grooves out and the tension increases all by itself. Better to just clean and apply 30 or 40 weight, if needed, on the normal service calls.

              Comment


              • #8
                Cinemecanica used to sell a silicone oil similar to damping fluid for their slutchs

                Comment


                • #9
                  We will agree to disagree then. Every location that I come across that oils the pads has problems because the oil attracts dirt which gets onto the clutch pad and cuts grooves into the aluminum or causes uneven take-up tension. Every location where I have installed new clean pads and had them taken out and cleaned as part of a PM has had more consistent take-up with less spring tension needed and I have never had a clean felt pad wear a groove into the aluminum clutch disk, but to each their own.

                  Comment


                  • #10
                    Well, talk to Tom at Kelmar then. He'll tell you just like he did me that the clutches are designed to be oiled and not run dry. Also that they should get serviced quarterly if used every day. How can dust get into the pad?,It's sandwiched in between two plates exactly the same size and the pad is under pressure from the spring loading? Also, I used synthetic oil on the pads. Not liquid Dinosaur molecules.
                    Dust problems with the tale up is like the last problem I ever had and many places out west and the entire Midwest are extremely dusty..

                    Comment


                    • #11
                      Interesting how everyone has a different theory on this.

                      I'm on the side of disassembling and cleaning the whole mechanism with naphtha (or some similar grease solvent) and replacing the pad with a new one that has one (large) drop of projector oil (though it probably should be something slightly thicker) on it. Not saturated, not dry. Then, run the machine for a few minutes while holding an empty reel on the shaft (not allowing it to spin). This will spread the oil across the pad and disks.

                      Ideally, you want a spring scale to set the take-up tension properly. For 2000' reels, it can be done by trial and error--you want the minimum tension necessary to give a tight wind. It's touchier for larger reels, especially with small diameter hubs.

                      Comment


                      • #12
                        Originally posted by Scott Norwood View Post
                        Interesting how everyone has a different theory on this.

                        I'm on the side of disassembling and cleaning the whole mechanism with naphtha (or some similar grease solvent) and replacing the pad with a new one that has one (large) drop of projector oil (though it probably should be something slightly thicker) on it. Not saturated, not dry. Then, run the machine for a few minutes while holding an empty reel on the shaft (not allowing it to spin). This will spread the oil across the pad and disks.

                        Ideally, you want a spring scale to set the take-up tension properly. For 2000' reels, it can be done by trial and error--you want the minimum tension necessary to give a tight wind. It's touchier for larger reels, especially with small diameter hubs.
                        I generally try to follow follow the recommended factory procedures, so it's not my opinion. If today's clutches were made of cast iron like they used to be then do what ever you want to. The parts probably are not going to wear out in the theaters useful life.. But todays stuff is all soft aluminum.

                        Comment


                        • #13
                          Where is Guttag when you need him to settle this?

                          Comment


                          • #14
                            Where is Guttag when you need him to settle this?
                            I was chatting with him just last night so he must have decided to steer clear of this one!

                            Comment


                            • #15
                              Kelmar? 7000 series? Run dry. I've seen some with an extremely light-weight oil on them (barely any) and it has done, o-k, I guess. But, by and large, if you put oil on them you get a black messy gooey pad that doesn't last as long. If you oil their rewinder clutch (same pad), you can add a racing stripe to your mess as it slings oil on the table, wall, what have you. Kelmar does claim to preload their clutches with SAE 40W ND oil. I'm not sure that is the case but if they do, it was applied VERY sparingly.

                              Comment

                              Working...
                              X