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-   -   Are Ceramic Tools Essential? (https://www.vintage-radio.net/forum/showthread.php?t=185004)

knobtwiddler 21st Oct 2021 10:44 pm

Are Ceramic Tools Essential?
 
Hi,

How essential is it to use non-magnetic screwdrivers and sockets when working on tape machines? I suppose an alternative would be to use a mains-powered demag machine once you've finished working?

Ceramic tools aren't only expensive, but I'm nervous that they aren't going to be as tough as their steel equivalents. On top of that, as tape machines are a hobby to me (I work in electronics and have plenty of test kit, but it's for actual work, not fun) I can't really jusitfy spending hundreds of quid on tools I might use once or twice a year. I have test tapes and alignment gauge, along with scopes and FFT machines etc.

My main interest at the moment is getting my cassette machines 100% so that I can transcribe precious tapes. I find that each machine will play certain tapes well, but not others. It seems that you need a variety of machines that are tip-top if you want to transcribe a collection decently.

I also have a 1/4" reel machine, but that is on the back-burner. It would be lovely to find time to get that up to scratch as well...

TIA

Ted Kendall 22nd Oct 2021 12:01 am

Re: Are Ceramic Tools Essential?
 
You don't want to wave magnetised tools around a tape transport, obviously, but ordinary steel, degaussed, is perfectly adequate. A degausser is much cheaper than fancy materials, anyway. Trouble is, so many screwdrivers seem to be magnetised intentionally these days.

TIMTAPE 22nd Oct 2021 2:06 am

Re: Are Ceramic Tools Essential?
 
I've had an old tape bulk eraser in my shop for a long time. If I'm in any doubt about a screwdriver or other tool before using it near a tape path I can degauss it in 5 seconds. It's be a very useful tool especially since it's always plugged into the mains and is activated by a push and hold switch, so it cant be accidentally left on to burn itself. I keep it on the other side of the room, well away from recorded tapes.

Not sure what you mean by needing a variety of cassette machines to optimise playback on a variety of cassette tapes.

Refugee 22nd Oct 2021 2:37 am

Re: Are Ceramic Tools Essential?
 
Ceramic scissors used to be sold for editing magnetic tape.
If you are worried use a simple demagnetising wand after working on a machine.
The bias oscillator does a pretty good job if record is left engaged for a few minutes with or without a tape in the machine.

barrymagrec 22nd Oct 2021 9:08 am

Re: Are Ceramic Tools Essential?
 
We never used special non magnetic tools when I was at Leevers Rich and I have never knowingly seen them in use anywhere else, including the BBC.

As mentioned above regular demagging of tools that get close to heads is sufficent.

Radio Wrangler 22nd Oct 2021 9:34 am

Re: Are Ceramic Tools Essential?
 
Ceramic tools are useful for tuning RF coils without much proximity effect, but that's about all. They are expensive and fragile. Demagnetisers are cheaper and more robust.

David

rontech 22nd Oct 2021 9:44 am

Re: Are Ceramic Tools Essential?
 
Plastic knitting needles with the point cut off and then filed to a chisel point can be useful

knobtwiddler 22nd Oct 2021 12:17 pm

Re: Are Ceramic Tools Essential?
 
I knew this was the best place to ask such a question! You have all been so helpful, thank you!

The 'Han D Mag' appears to be an industry-standard with pros (I have an old TDK hand-held unit that I bought at Laskys, but I very much doubt it'll have enough puff in it). I will have to ask Santa for the Han D -)


Quote:

Not sure what you mean by needing a variety of cassette machines to optimise playback on a variety of cassette tapes.
Although most of my decks are in states of disrepair, I have a couple of decent Sony + Technics decks. I find that a tape that sounds good in one of them, will not have the top-end clarity on the other, and vice-versa. I put it down to shell azimuth, not tape formulation. The way around this would be to buy a machine with PB azimuth adjust, i.e. Nak CR7. However, we are at the top of the market, and it's very easy to spend a fortune on a worn out machine. I also worry that the HF clarity could be due to other issues, such as tape age (some haven't aged as well as others). I should start another thread, asking 'how much of a life-saver is adjustable PB azimuth?'.

Thanks

mark_in_manc 22nd Oct 2021 12:50 pm

Re: Are Ceramic Tools Essential?
 
I think you're right about azimuth. I seem to remember most of the tape decks I used to play with as a teenager (70s and 80s cheap stuff, including boom boxes and music centres) had an azimuth screw which you could get at while the tape was running. That was how we used to set it - put a pre-recorded tape in (which hopefully had been recorded on a lined-up machine) and then twiddle for maximum top end.

Later at the BBC I seem to remember a Lindos gizmo (?) with which to measure while twiddling fancy Studer cassette players - but it did the same job!

This comes to mind because maybe 20 years ago I dredged this info to the front of my mind to impress a girl who was working in the RTE music library and was going mad with a tape deck (just before internet music, I guess!) and playing her tapes at home on the most out-of-alignment music centre imaginable. Alas, she was not _that_ impressed :)

G6Tanuki 22nd Oct 2021 6:15 pm

Re: Are Ceramic Tools Essential?
 
The IBM guys who used to service the reel-to-reel tapedrives on our mainframes used tools that looked to be made of Brass.

Their 'alignment' process was basically to put the drive into 'maintenance' mode, load a reference tape they brought with them, attach a little box with a bunch of 7-segment LEDs on the front, then the drive did a 'fast-forward' and they twiddled the azimuth/elevation contols on the drive to get the lowest aggregate reading across the nine data-stripes on the tape.

In practice you could never get all-zeros across all nine channels.

TIMTAPE 22nd Oct 2021 6:54 pm

Re: Are Ceramic Tools Essential?
 
1 Attachment(s)
Designing a cassette deck with a front panel azimuth adjuster could be tricky for the manufacturer because the head moves forward and back and so does the relevant azimuth screw. Often the screw is only accessible when the deck is in play mode so you can't leave a small adjuster screwdriver attached to the screw without doing damage. By contrast, open reel deck heads are stationary, making things simpler. For easy regular adjustment of azimuth it's probably either one of the rare Nakamichi models with the adjuster built in, or some other mod to an existing deck. Even cutting away part of a panel so a small driver can remain permanently attached to the azimuth screw without fouling can be a great help.

I suspect regularly azimuth adjusting is often not done because it's too fiddly. That seemed like a good incentive to work out a way to make adjusting easier, at least having many cassettes to transfer. Making adjusting easier, and avoiding the expense, was the incentive I needed to make some mods myself. Ugly mod? Probably, but for me it's a tool, a means to an end, not an object of worship.

TIMTAPE 22nd Oct 2021 7:35 pm

Re: Are Ceramic Tools Essential?
 
Just to add, this also avoids accidentally magnetising the head via one of those confounded magnetised screwdrivers.

Refugee 23rd Oct 2021 12:57 am

Re: Are Ceramic Tools Essential?
 
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We can always confuse everyone by having a flip over head auto reverse deck.
There is two screws. There is one for each direction and very little ferrous metal to worry about.
There are two twiddling holes in the cassette cover for twiddlers to get at:o

jamesperrett 23rd Oct 2021 1:09 am

Re: Are Ceramic Tools Essential?
 
Quote:

Originally Posted by knobtwiddler (Post 1416431)
Although most of my decks are in states of disrepair, I have a couple of decent Sony + Technics decks. I find that a tape that sounds good in one of them, will not have the top-end clarity on the other, and vice-versa. I put it down to shell azimuth, not tape formulation. The way around this would be to buy a machine with PB azimuth adjust, i.e. Nak CR7. However, we are at the top of the market, and it's very easy to spend a fortune on a worn out machine. I also worry that the HF clarity could be due to other issues, such as tape age (some haven't aged as well as others). I should start another thread, asking 'how much of a life-saver is adjustable PB azimuth?'.

The standard practice for me is to adjust the azimuth for just about every cassette I play. You don't need a special machine - every cassette recorder I have ever encountered has had a removable cover that allows easy access to the azimuth adjustment screw. We are often only talking about a small adjustment but it makes a big difference.

TIMTAPE 23rd Oct 2021 2:56 am

Re: Are Ceramic Tools Essential?
 
I agree James. For transferring a lot of cassettes though, adjusting the factory azimuth screw especially multiple times can lead to problems. Most tape players were never designed for regular adjusting of that tiny unlubricated screw, and on a deck with a worn (grooved) tape head, adjusting azimuth can crease the tape or worse. It certainly requires care.

knobtwiddler 23rd Oct 2021 9:52 am

Re: Are Ceramic Tools Essential?
 
Thanks.

I have a couple of full-track azimuth adjust tapes. My feeling has always been that unless the machine has PB azimuth as a design feature, I am risking curling the tape (as well as loosening the screw / nut over time, which is a concern, considering the carriage moves up / down quite a lot).

My tapes are important to me, but I am concerned about getting a Nak, as we're at the top of the market for such things, and it's very easy to get straddled with a dog (you don't see heads under the microscope in the sales photos!). The plastic wheels that adjust the head make me nervous as well - after 30-40 years, how tough will they be?

My Technics has a specially-designed Record azimuth screw, but the PB one isn't easily accessed. I also note that the screws used to retain head on many decks have quite coarse threads... I would've thought you'd want a very find pitch one. It does seem to me that it could be quite easy to skew the tape if being clumsy. It also seems to me that the Nak systems (particularly elaborate automatic ones) have plenty of scope for maintenance issues after 30-odd years, mechanically and electronics-wise.

edit: and another thing: the only Nak with Quartz lock is the Dragon. The main tech for Naks in Europe now refuses to take on Dragons, as he says 9/10 have worn heads. Although non-QL machines can give excellent W+F, QL gives peace of mind in terms of hearing at the right pitch. All my Sony machines have QL. And they also have other innovations that Nak never did. One magazine showed the Sony 666 to have lower modulation noise than the Nak 505.

TIMTAPE 24th Oct 2021 3:05 am

Re: Are Ceramic Tools Essential?
 
1 Attachment(s)
Quote:

Originally Posted by knobtwiddler (Post 1416695)
Thanks.

I have a couple of full-track azimuth adjust tapes.

When it's only transferrring old recordings these reference tapes are of no use. Each old cassette recording we want to transfer is now our "azimuth adjust tape".

Quote:

Originally Posted by knobtwiddler (Post 1416695)
My feeling has always been that unless the machine has PB azimuth as a design feature, I am risking curling the tape (as well as loosening the screw / nut over time, which is a concern, considering the carriage moves up / down quite a lot).

Not really. Standard cassette heads were designed with a tape guide fixed to only one side. The azimuth screw mostly adjusts height on the opposite side of the head. So with azimuth adjustment the guide height should only rise or fall minimally. As James says, often the azimuth deviation adjustment needed is only small re nominal. But yes a worn head can cause problems if the adjusting of azimuth tends to lift the tape out of the head's wear groove, making the audio worse, rather than better. But what are we doing transferring valuable tapes with a worn head? The head face should be pristine.

Quote:

Originally Posted by knobtwiddler (Post 1416695)
My tapes are important to me, but I am concerned about getting a Nak, as we're at the top of the market for such things, and it's very easy to get straddled with a dog (you don't see heads under the microscope in the sales photos!).

Yes and when photos are presented in online adverts they are often poor in showing the head's real condition.

Quote:

Originally Posted by knobtwiddler (Post 1416695)
The plastic wheels that adjust the head make me nervous as well - after 30-40 years, how tough will they be?

The Nak head mounting and adjusting mech is delicate but if treated with care it's fine I've found. I broke a tiny plastic mounting part in a Nak once, and it taught me to be careful from then on. The small white plastic adjusters I've never had a problem with but the key obviously is being careful.

Quote:

Originally Posted by knobtwiddler (Post 1416695)
My Technics has a specially-designed Record azimuth screw, but the PB one isn't easily accessed.

I have a Sony ES deck. Nice little machine but access to the repro head azimuth screw is poor, and mods to fix this would be difficult. So the Sony is rarely used. Similarly the Tascam 122 MK III is a great deck in many ways and many archivists use them, but access to the playback azimuth is very poor.

Quote:

Originally Posted by knobtwiddler (Post 1416695)
I also note that the screws used to retain head on many decks have quite coarse threads... I would've thought you'd want a very find pitch one. It does seem to me that it could be quite easy to skew the tape if being clumsy.

Yes a finer threaded screw would often help but I've not felt the need to make that particular mod. If the azimuth needs to be adjusted further than usual obviously we take more care. For those who mindlessly adjust the screw so far out that it completely falls out, and does other damage, what can one say?

Quote:

Originally Posted by knobtwiddler (Post 1416695)
It also seems to me that the Nak systems (particularly elaborate automatic ones) have plenty of scope for maintenance issues after 30-odd years, mechanically and electronics-wise.

Yes that applies to old gear generally but tape and video decks are complex beasts and maintenance hungry, as they always were, but 40 years on, the maintenance issues have usually multiplied. Some of the top decks are beltless which saves on maintenance but there will still be issues, just a few less of them.

Quote:

Originally Posted by knobtwiddler (Post 1416695)
edit: and another thing: the only Nak with Quartz lock is the Dragon.

The quartz lock is good but only covers the capstan motors. It doesnt cover mechanical issues.

Quote:

Originally Posted by knobtwiddler (Post 1416695)
The main tech for Naks in Europe now refuses to take on Dragons, as he says 9/10 have worn heads.

Those heads have been wearing for a long time now! Worse, the Dragon's special 3 track play head, essential to the operation of the auto azimuth system, is basically made of unobtainium.
Knowing this, I'd never buy a Dragon for the auto azimuth feature which actually has its limitations even if working at its best. Richard Hess says it is very slow to react, and only works if the right track from which it gets its information carries a good, strong signal. Not good for archival tapes in all sorts of condition.

Having said that, cassette heads can be relapped, including the special Dragon repro head. I wonder if the fellow in Europe relaps them.
Nak classic heads are actually easier to relap than most other cassette heads because they have no attached guide in the way. All my Nak record or play heads I've relapped, some more than once.

For me one of the much more affordable dual capstan Naks is a more realistic purchase for high quality transfers. Of course they need to be in good working condition.

See photo of a mod I made to another Nak 480. The plastic azimuth adjuster already has a hole moulded in its centre. I found a piece of wire which fitted snugly in the hole and allowed me to make the front panel adjuster without much effort. A piece of wire, a small plastic knob and some careful filing of a few deck parts to allow clearance. The exposed adjuster is vulnerable though. I should fit a shroud around it to protect it from accidental knocks.

Note too another unusual Nak feature: the white wheel to the left allows easy head height adjustment. Not needed as often as azimuth but good to have. I made a felt pen mark on the screw at the 12 o'clock position to indicate standard height.

knobtwiddler 24th Oct 2021 11:33 am

Re: Are Ceramic Tools Essential?
 
Thank you, Tim - very thought provoking.

It's looking to me that, for serious archiving jobs, either I will have to modify a machine as you have done, or find a good CR-7.

I really like the Sony ES machines and have 2 of them, with another coming from Japan. However, as you say, getting access to the azimuth screw requires the removal of various parts (shield for one) that are designed to be in-place during playback. I'd have to take door off (v. easy), but then remove screws for shield (easy to lose...), adjust *for that particular tape*, and then screw back on... Bit of a PITA.

TIMTAPE 24th Oct 2021 1:52 pm

Re: Are Ceramic Tools Essential?
 
I guess I've just gotten used to the convenience front panel adjuster now. Adjusting the head azimuth with a small driver should be OK so long as it's done carefully. Many people seem to do it this way.

Linnovice 29th Oct 2021 9:09 pm

Re: Are Ceramic Tools Essential?
 
Ok, I’ll ask the dumb question. How do you demag a screwdriver with a bulk eraser? Do you just lay it on top for a few seconds or do you have to slowly draw it away?


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