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Author Topic: Will Tape Damage Otari Heads During Rewind?  (Read 4419 times)

Offline commonman

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Will Tape Damage Otari Heads During Rewind?
« on: October 09, 2008, 08:28:49 PM »
I'm using an Otari MX 5050 QXHD.  I noticed that when I rewind or fast forward, the tape IS NOT lifted by anything and therefore runs at high speed across the heads.  This worries me.  I'm almost sure, that my Tascam (can't remember model but it was a professional 8 track) automatically lifted the tape whenever I rewound or fast forwarded.  Or, at the very least, it gave you the option of lifting the tape for long rewinds or forwards. 

There is a bar on the Otari that I can see could act as a "tape lifter" and it seems to be connected to a "cue" lever but it does not seem to work, or at least it does not lift the tape off the heads (maybe the spring is broken).

Am I wearing my heads out when I rewind and fast-forward?  What can I do?
Jim Freschi

Offline ironbut

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Re: Will Tape Damage Otari Heads During Rewind?
« Reply #1 on: October 09, 2008, 09:12:33 PM »
Am I wearing my heads out when I rewind and fast-forward?  What can I do?

Yep! The bar (tape lifter) should be engaging in fast forward or rewind. The cue switch disengages the lifter so it could be stuck on. More likely, the lifter or the linkage that engages the lifter, is gummed up with hardened grease. First try and move the lifter  with your finger. If it's just loose, the problem is farther back in the linkage. I've never worked on an Otari but many machines will have a solenoid that moves the pinch rollers and the lifter. If the pinch rollers are engaging on play it's probably the linkage between the two. If you open the back of your Otari, you may be able to get to these linkages (mechanical) and follow it from the lifter itself and manually see if each linkage is working freely. Adding a little alcohol with a Q tip can help melt the grease. You'd be surprised how hard grease can get though. Be careful though. Don't bend anything or inadvertently disconnect any wires (it can get a little tight around the head area since that's where lots of things are happening. If you're unlucky, you may even have to remove a motor to get at the problem.
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Offline commonman

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Re: Will Tape Damage Otari Heads During Rewind?
« Reply #2 on: October 09, 2008, 09:28:51 PM »
Thanks for the fast response and the info.

Let me ask one more thing.  You say, "The cue switch disengages the lifter."  Does this mean when I move the lever to the "cue" position" then the tape WILL NOT be lifted off the heads?  And when the bar is in the opposite position, the tape should be lifted off the heads when rewinding and fast forwarding?

Jim Freschi

Offline ironbut

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Re: Will Tape Damage Otari Heads During Rewind?
« Reply #3 on: October 09, 2008, 09:36:45 PM »
Yes, the cue is used for editing. When you're looking for a particular spot on a tape (to edit out or to add something at that point) you engage the cue and the lifter disengages (it's usually engaged when the machine is stopped) allowing the tape to be manually moved across the heads by turning the reels back and forth and listening for the spot. You'd then mark that spot on the playback head and pull the tape down to a splicing block (which is why many machines have a block attached right by the head assembly).
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Offline commonman

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Re: Will Tape Damage Otari Heads During Rewind?
« Reply #4 on: October 12, 2008, 06:24:48 PM »
Ah Yes, it's all coming back to me now, thanks to your response and input.
So, thank you very much.
Jim Freschi

Offline Ki Choi

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Re: Will Tape Damage Otari Heads During Rewind?
« Reply #5 on: October 21, 2008, 01:40:14 PM »
I am not sure which model you have but if it is a MX-5050 II or III, you can by pass the head assembly by threading your tape over the headcover and ff or rewind the tape without the tape making contacts with any of the tape guides or the heads.  Of course you need to let the tape go through both the supply and take up dancer/tension arms.

Studer A810 is another deck that the head assembly can be by passed when fast forwarding or rewinding the tape.  One of my A810s spends most of its time providing quality rewiding with near perfect tape pact especially in its Library wind mode (Trans key + Rew).

Ki
Ki Choi