RMGI 900 oxide shed problem

[[email protected]]

I've been using Quantegy 499 with my Tascam MS-16 for a few years with
the bare minimum of shedding, and I've been reading that people are
wary of buying the end run of 499, so I figured I'd try the RMGI 900
as a replacement.

With the 499 I'd be fine to clean before every session, and only get a
tiny amount of tape gunk from the corners of the tape guides, and the
heads would be nearly spotless. A couple of days ago I did my first
session on RMGI 900, and about 5 hours in a vocal track had numerous
dropouts, so I figured a normal cleaning would fix it, which it did,
but the tape path was COVERED in fine oxide dust (the deck is mounted
vertically. I've never seen that much dust. I was even an idiot for
several sessions in a row with 499 and NO cleaning, and never saw
anything like that. Yes, I'm a terrible engineer.

Otherwise, the tape seems to be lower noise than the 499, but other
changes have been made recently, so I can't say for sure. Has anyone
else tried the new 900?

[Scott Dorsey]

In article . com>,
> wrote:
>I've been using Quantegy 499 with my Tascam MS-16 for a few years with
>the bare minimum of shedding, and I've been reading that people are
>wary of buying the end run of 499, so I figured I'd try the RMGI 900
>as a replacement.
>
>With the 499 I'd be fine to clean before every session, and only get a
>tiny amount of tape gunk from the corners of the tape guides, and the
>heads would be nearly spotless. A couple of days ago I did my first
>session on RMGI 900, and about 5 hours in a vocal track had numerous
>dropouts, so I figured a normal cleaning would fix it, which it did,
>but the tape path was COVERED in fine oxide dust (the deck is mounted
>vertically. I've never seen that much dust. I was even an idiot for
>several sessions in a row with 499 and NO cleaning, and never saw
>anything like that. Yes, I'm a terrible engineer.
>
>Otherwise, the tape seems to be lower noise than the 499, but other
>changes have been made recently, so I can't say for sure. Has anyone
>else tried the new 900?

I have tried the 900 without shedding issues, but only on the Nagra and
ATR-100 machines.

Now, you're not getting _any_ buildup on the heads, right, just on the
guides? If you clean the guides very well, scrubbing very hard with
xylene on a q-tip, does the problem persist afterward?

There are a couple possibilities: when Agfa was making those tapes (before
BASF took over the line), they had some severe shedding problems, and I
would see something like what you describe except that it would shed across
the entire tape path. It's possible those have come back (and back then
people just lived with it and cleaned the heads a lot).

Another possibility is that you started up with guides that were gunked up,
and that's scraping the edges of the tape. The RMGI tape is slit more
precisely than the Ampex, so if the tape path is just a little too narrow,
you'll see shedding at the guides and if you look at the tape with a
magnifier you will see wear on the edges but not the center.

It's a good idea to clean the heads every time you put a reel on, though.
Especially now that most of us are stuck cleaning with isopropanol.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Apr 2, 2:46 pm, (Scott Dorsey) wrote:
> In article . com>,
>
>
>
> > wrote:
> >I've been using Quantegy 499 with my Tascam MS-16 for a few years with
> >the bare minimum of shedding, and I've been reading that people are
> >wary of buying the end run of 499, so I figured I'd try the RMGI 900
> >as a replacement.
>
> >With the 499 I'd be fine to clean before every session, and only get a
> >tiny amount of tape gunk from the corners of the tape guides, and the
> >heads would be nearly spotless. A couple of days ago I did my first
> >session on RMGI 900, and about 5 hours in a vocal track had numerous
> >dropouts, so I figured a normal cleaning would fix it, which it did,
> >but the tape path was COVERED in fine oxide dust (the deck is mounted
> >vertically. I've never seen that much dust. I was even an idiot for
> >several sessions in a row with 499 and NO cleaning, and never saw
> >anything like that. Yes, I'm a terrible engineer.
>
> >Otherwise, the tape seems to be lower noise than the 499, but other
> >changes have been made recently, so I can't say for sure. Has anyone
> >else tried the new 900?
>
> I have tried the 900 without shedding issues, but only on the Nagra and
> ATR-100 machines.
>
> Now, you're not getting _any_ buildup on the heads, right, just on the
> guides? If you clean the guides very well, scrubbing very hard with
> xylene on a q-tip, does the problem persist afterward?
>
> There are a couple possibilities: when Agfa was making those tapes (before
> BASF took over the line), they had some severe shedding problems, and I
> would see something like what you describe except that it would shed across
> the entire tape path. It's possible those have come back (and back then
> people just lived with it and cleaned the heads a lot).
>
> Another possibility is that you started up with guides that were gunked up,
> and that's scraping the edges of the tape. The RMGI tape is slit more
> precisely than the Ampex, so if the tape path is just a little too narrow,
> you'll see shedding at the guides and if you look at the tape with a
> magnifier you will see wear on the edges but not the center.
>
> It's a good idea to clean the heads every time you put a reel on, though.
> Especially now that most of us are stuck cleaning with isopropanol.
> --scott
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

Thanks Scott,
I am getting buildup on the heads (causing the low or fluctuating
record levels), but oddly not so much on the guides (which usually
only accumulate a small amount of gunk in the corners over time), but
the smooth straight guide and lifters got coated in fine dust. I
don't have xylene, just the iso, and I did clean well before this
session. After my last lapse I've been diligent, and will continue.
I'll check the edges of the tape for wear there, but I've seen edge
shed before, and it was very different from what I'm seeing now.

I forgot to mention before that from the moment I wound it through the
machine, the odor seemed stronger than the 499. I wondered if it has
higher oxide content than the 499, but I thought they were supposed to
be similar, or at least bias compatible.

[Mike Rivers]

On Apr 2, 3:59 pm, wrote:

> I forgot to mention before that from the moment I wound it through the
> machine, the odor seemed stronger than the 499. I wondered if it has
> higher oxide content than the 499, but I thought they were supposed to
> be similar, or at least bias compatible.

The binder is what smells, not the oxide. And it's the binder that
gums up the works (in addition to holding the oxide particles together
and sticking them to the tape).

[Scott Dorsey]

> wrote:
>I am getting buildup on the heads (causing the low or fluctuating
>record levels), but oddly not so much on the guides (which usually
>only accumulate a small amount of gunk in the corners over time), but
>the smooth straight guide and lifters got coated in fine dust.

That sounds like straight shedding, and it's not an issue if you keep
the thing clean, but it is a pain in the neck.

>I
>don't have xylene, just the iso, and I did clean well before this
>session. After my last lapse I've been diligent, and will continue.
>I'll check the edges of the tape for wear there, but I've seen edge
>shed before, and it was very different from what I'm seeing now.

Clean well every time you change reels. Once you know where your machine's
tape path tends to collect oxide, you'll know where to scrub. Xylene is
faster than isopropanol but is bad for you; you can get a Freon TF equivalent
from Precision Motor Works called Head, Red and Roll cleaner. It's good.

Also check your heads to see if they have gone flat... excessive head wear
will also cause more shedding. And call the RMGI guys and mention it to
them.

>I forgot to mention before that from the moment I wound it through the
>machine, the odor seemed stronger than the 499. I wondered if it has
>higher oxide content than the 499, but I thought they were supposed to
>be similar, or at least bias compatible.

They are only vaguely similar, and anybody who tells you 499 is even
bias-compatible with itself is lying. The binder chemistry is very different
than that of the Ampex tapes which is why it smells so different.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."