Proper Way to Align Reel Table

[jcmusic]

What would be the best way to align the reel table so that the tape is in line with the tensioners?

Jay

[bobschneider]

I just look at whether the tape is centered on the reel as I play or rewind the tape.  If it's not, I adjust the table until it is.

[ironbut]

I've found this to be a "feel as you go" sort of thing.
If you collect a lot of old tapes like I do, then the plastic 7" reels pretty much make the rough adjustments. Of course, some will be so bad that you just can't freakin' win! That's one of the reasons I keep a nice stock of empty reels on hand (the low torque, big hub reels are preferable but since they're no longer being made, the regular 7inchers will do). I just keep the old reel in the plastic slip cover with the boxed new reel. An added benefit to having the empty original,.. you can actually read it while it's being played on side two!

Oops, back on subject.
So I find a spot that most 7inchers won't rub and then move onto the 10.5" aluminum reels. I use a spacer to almost equal the thickness of the 7's and since all my 10.5" tapes are 1/2 track, it only has to work on one side (no tape flip). When I look at my large reels, they aren't wound exactly in the center. They're just a tad toward the outside (which means that I could probably use another 1/64th inch thicker spacer) but it doesn't flange at all.

Flanging is a pretty serious problem. It damages the tape edge and will keep the tape from getting a proper wind eventually. If you've read about the problems with uneven slitting of tape into the proper widths, this is just as bad. It will cause the edges to shed oxide and while there is a border between the recorded track and the tape edge, it could eventually cause a loss of signal in that channel (it really depends on how badly it scrapes and flexes the tape when it does). These problems are more obvious from old 1/4 track tapes since they have less "real estate" to loose.
Anyway, it's annoying as hell!

[jcmusic]

In your opinion what would be more important, getting the tape to wind in the center of the reel; or getting the tape to line up with the tensioners?

Jay

[Tim]

The tension arm rollers can get out of alignment due to impact, tampering, shipping damage, so that's a good question.  First, thread the tape without the tension arms.  Adjust the reel table heights so that the tape runs in the center of the flanges.  Then thread up the tension-arms and see if there is any change to the tape being centered in the reel flanges.  If so, adjust the tension arm heights.  This gets both the tension rollers and the tape reels at the same heights as the headblock entrance and exit guides.  It's also a good idea while you're at it to check the azimuth and zenith of the tension arm rollers before adjusting their heights in case the tension arms were impacted/bent. (the rollers should be parallel to the headblock tape guides)

Tim

[ironbut]

In my first reply, I talked about the different formats and the relative needs of each. So it really depends on what tapes you're playing. Tapes that need to be "flipped" need to have the tape centered in the reel more than 1/2 tracks. There's nothing wrong with having a tape wind a little off center. After all, some reels are thicker than others so you aren't going to adjust reel table height every time you change the tape.

In a perfect world, the tape should travel down the center of every guide, tensioner and capstan and never touch either edge guide on any of these. Of course, edge wear and imperfect slitting causes some "wander" of the tape and it does from time to time touch those edges. You want to minimize this by adjusting everything so that when the tape is centered on the heads, the chances of it touching the edges is minimal. A great many of the adjustments on your machine are shooting toward this ideal.

It's only after you have these adjustment as perfectly as you can, that you start trying to get reel height adjusted.

[jcmusic]

Well I just had the heads relapped, so I am thinking the heads are in line as they should be.

Jay

[ironbut]

This Post has been removed.
 The reason for it's removal will be posted further down in this thread.

[jcmusic]

 Well Steve what you are saying seems to make some sense, but the heads were optically aligned by JRF and according to them any adjustments would be minute at best. I am not having any problems with the sound just the tape squeal.

Jay

[microstrip]

Can I assume that after rellaping an head must be moved slightly forward to compensate for the removed material?
This can be a problem with some head assemblies.

[jcmusic]

You can assume anything you want, I don't really know. I only know what I was told by the John French and he is suppose to be THE AUTHORITY on this matter!!!

Jay

[steveidosound]

If all this is in reference to an Otari head block sent to JRF, it is my understanding they do align everything precisely on a reference Otari machine.
This should mean the guides and heads are now perfect. Whether the rest of your machine is perfect is a question.
Presuming there is no issue with the capstan and pinch roller, aligning the turntables as was suggested above, then referencing the tensioners to the properly aligned turntables and headblock - making sure nothing has been tweaked out of alignment with them and correcting if that is the case, should produce correct alignment of all if tape tension is also correct.

[ironbut]

It's been pointed out to me that my last post in the thread was at best, horribly unclear and at worst, just plain wrong.

My intent was to point out that professional relapping facilities of the caliber of JFR optically align the heads once they're remounted and adjustments should be verified by using a test tape (in the original post I said visually which is certainly much different than what actually occurs there).

I used JFR as an example of a premium service and product provider, but of course, I had no idea who had done the work on Jay's heads at that time. What followed were examples of what could happen if a lesser service was used (like your local audio repair shop).
Unfortunately, I didn't make it clear that only the beginning of the paragraph referred to JFR and where examples of poor workmanship began.

I apologize if I misled any members who read this posting and as always, begfor any corrections to any misleading, factually incorrect, or down right stupid posts that I'm sure I've made in past and will make in future postings.

thanks for your understanding
Skeve