How often to clean tape path?

[Beck]

Tim,

What do you make of what appears to be an "oxide line" at the top of the tape path, especially on the two rollers at either side of the pic and the capstan? Is it possible that there's either something abrading the top edge of the tape or an alignment issue affecting it in that area.

ChrisO

Not sure, but yeah if the reel tables are too high or the guides too low, or both there could be some excessive rubbing at those points. Also the upper part on the rollers could be easier to miss while cleaning so might have some buildup. The oxide on the capstan is pretty even, which is typical of shedding tape. IMO, this is way to much oxide comming off regardless.

just a comment from my experience with the RMGI tape...I know a lot of 1/2" decks were setup for the 12.5mm tape popularized by, um, Ampex/Quantegy right? Whereas the RMGI tape is slit at the more true 12.7mm standard. Is there any potential issue like this for the 1/4" tape?

This shouldn't be an issue with 1/4". Here are the widths for some common 1/4" tapes:

3M/Scotch 207 -- 6.35mm
RMGI LPR35 -- 6.3mm
Ampex/Quantegy 407/457 -- 6.3mm
Maxell UD 35-90 -- 6.25mm

Not a huge difference. I suppose it's possible if the lifters are worn flat with narrower tape, but I remain sceptical about the width explanation from RMGI. Besides, worn lifters will cut into tape no matter what kind of tape wore them down. One thing nddhc could try is to clean the tape path really well and then play the tape from beginning to end... no rewinding or fast forward so the lifters won't touch the tape. The lifters don’t look worn to me from the pics, but it’s something to try.

The guy left me with a few boxes of open, used Ampex 457 and suffered badly from Sticky Shed. From the box design it looks like it is from the late 80s. Im not sure what other tape to try besides RMGI that I can still purchase new?

You can get the tapes that I listed in my previous post from eBay. You might even be able to find a reel at a local Radio Shack, but they’ve stopped making them. They had them at my local RS as recently as a year ago. The best bet is to look for a Radio Shack dealer in the phonebook. They are a bit different than the regular RS stores because they keep a lot of old stuff on the shelves. RS dealers are usually part of another store like ACE or True Value Hardware.

By the way, I’ve always used denatured alcohol for cleaning tape paths since my A/V days (1978), but don’t use it on rubber. It’s actually the purest alcohol, evaporates quickly and leaves no moisture or residue behind. But a lot of folks use 91% Isopropyl or greater with good results. You will have to get 99% to equal the properties of denatured.

 

[nddhc]

I still haven't been able to get my hands on a decent camera - but on close inspection the tape lifters do have a very, very small flat spot. This might be the cause of my troubles?

At the same time, Media Distributors told me that LPR35 is not a big seller for them, so perhaps the stock they do have has been sitting for quite a while (an early RMGI batch maybe..?)

Im assuming it should be possible to rotate the tape lifters myself? Ill look in the service manual for any info.

 

[sweetbeats]

alcohol...

Tim,

By the way, I’ve always used denatured alcohol for cleaning tape paths since my A/V days (1978), but don’t use it on rubber. It’s actually the purest alcohol, evaporates quickly and leaves no moisture or residue behind. But a lot of folks use 91% Isopropyl or greater with good results. You will have to get 99% to equal the properties of denatured.

Can you link some references on this? Not trying to challenge...it would be nice to have a reference to this.

My understanding is that the performance/properties of the denatured alcohol depends on the additive that makes it 'denatured'; that denatured alcohol is simply ethyl alcohol (the drinking kind) that has been "denatured" (made unfit for consumption) by adding (in about a 70/30 solution) some additive...it may be isopropyl alcohol, benzine, methanol, ethanol, etc...even gasoline. So wouldn't the performance of it depend on what the additive is? So that's why I've used the 91% or greater anhydrous isopropyl (rubbing) alcohol. I want to use what's best but it seems that not all denatured alcohol is created equal. Can you help with this?

 

[sweetbeats]

I still haven't been able to get my hands on a decent camera - but on close inspection the tape lifters do have a very, very small flat spot. This might be the cause of my troubles?

probably not. can you rub your fingernail on the lifter post and feel any ridge or anything?

At the same time, Media Distributors told me that LPR35 is not a big seller for them, so perhaps the stock they do have has been sitting for quite a while (an early RMGI batch maybe..?)

Oooo...that is definitely plausible. Again, you'll have to wait for Phil to respond, but it could serve to calm your mind while you wait.

Im assuming it should be possible to rotate the tape lifters myself? Ill look in the service manual for any info.

Maybe, maybe not. I only know for sure about the Tascam 30/40/50 series decks. The lifters are non-rotating fixed guides. I've heard of people rotating them via force, and I've heard of successes doing this, but was freaky for the user in case. At any rate if your flattened areas are "very, very small", its not something you should be worrying about now IMHO. Lifters would have to be in obviously bad condition to cause that amount of shedding on good tape.

 

[nddhc]

It seems like I can feel a very slight ridge on the rightmost lifter, but not on the left. It should also be worth noting that during rewind I will sometimes hear quiet bursts of sound- so the tape must be slightly hitting the heads every so often.

Instead of rotating, couldn't I just put some sort of shrink tubing over the lifters to be on the safe side? Something like this - http://www.redco.com/shopexd.asp?id=416

 

[sweetbeats]

Instead of rotating, couldn't I just put some sort of shrink tubing over the lifters to be on the safe side? Something like this - http://www.redco.com/shopexd.asp?id=416

nononono.

I have heard of having custom sleeves precision machined and pressed onto old/worn lifters, but they need to be smooth and slick. shrink tubing is neither, at least to the degree needed. nddhc, your lifters don't sound to be in any concerning condition as far as wear, but if you can periodically hear audio during fast-winding you've either got a sticky lifter linkage or a faulty lifter solenoid....

That could contribute to premature tape path wear and tape shedding especially on bad tape.

When you are in REW mode, can you manually extend your lifters further by pushing with your finger?

 

[nddhc]

When you are in REW mode, can you manually extend your lifters further by pushing with your finger?

Yes, they can be pushed down slightly. Also, upon further inspection of the right lifter there definitely is a slight tape groove.

 

[Beck]

Tim,

Can you link some references on this? Not trying to challenge...it would be nice to have a reference to this.

Be glad too... check the last paragraph in the following link. The guy has been recording for decades and really knows his stuff.

https://homerecording.com/bbs/showpost.php?p=2929450&postcount=21





















Seriously though, I'll post a few references tonight sometime. Right now I'm in the middle of writing a scathing email to megaboxwarehouse. It’s real zinger They probably think I will eventually just go away... now that's funny. I'm sure a few regular members here will get a laugh out of the concept of me ever quiting or going away. Say a prayer for megaboxwarehouse.

 

[sweetbeats]

Be glad too... check the last paragraph in the following link. The guy has been recording for decades and really knows his stuff.

Beck...yer a nut. I totally went there, and I'm, like "Wait minute, this is just a post in this thread...wrong link...?....OHHHH I get it!"

Seriously though, I'm not questioning you per se... hope you don't feel that way. I've just been guided both ways and your advisement is definitive and I want to tap your brain and hence the source.

Say a prayer for megaboxwarehouse.

I will!

nddhc, do what Beck said and load yer RMGI tape and play it from beginning to end to keep the lifters off of it and see what it leaves on the tape path. It'll tell you something about what the lifters are contributing to the problem.

 

[nddhc]

Im in the process of playing the tape front-to-back and that should rule out (or point me in the direction) of the tape lifters and guides. Ive attached some pictures to show the machine with tape playing on it, if that helps at all.

After looking through the service manual, the only maintenance I see is adjusting reel tension, etc, which requires tools that I do not own or have access to. I see nothing about adjusting the tape path? Ive uploaded the manual to rapidshare in case anyone wants to take a look at it as well. Please let me know if I somehow missed something important. http://rapidshare.de/files/39474645/R8_sm.pdf.html

 

[A Reel Person]

From some...

From some of the technical papers written by industry experts and posted on this forum, most of which I've read, I remember a particular research paper that said there's no harm in "baking" any reel tape from any vendor or any time period, any time before use, even new tape right out of the box which you'd not otherwise suspect. It's just good insurance.

Just bake it as a rule and you'll bee cool!
I got my Snackmaster, 'cause I'm no fool! [Heh].

Serious point: Sticky Shed is Ugly and can sometimes cause Damage!

 

[sweetbeats]

nddhc,

It looks to me like the right guide needs to be adjusted out. If I look at your rec/repro head the tape doesn't appear centered. It may be getting pulled against the top (in the photo) of the guide causing some of the shedding. I'd raise that guide, and wait fr Phil Paske's call.

 

[nddhc]

sweetbeats -

Is this what you mean by the right guide? Do you think I could adjust it by loosening the hex screw at the top? Again, the service manual has kind of left me in the dark on some of these simple adjustments

 

[sweetbeats]

Yes, sorry, that's what I meant...in other words the guide on the takeup side.

Its hard to say how it adjusts as I don't have any hands-on experience with Fostex atr's, but you could just do some trial and error to see how it works if you're comfortable with that...

I read the service manual you linked and you are right...there really isn't anything in there of significance regarding tape path adjustments, it is hard to tell from the parts schematic how the guide adjustment is accomplished. Is there anything in the operations manual about that? Sorry I'm not much help.

 

[nddhc]

In the service manual it looks like that guide is only attached by the screw. When I tried loosening it, it was very, very tough as if it was glued in place. I knew the R8 could be troublesome to align,repair, etc before purchase.. but for the price I paid I really cant complain

I signed up for the R8 yahoo group and maybe they will have some tips for me about tape path alignment.

 

[sweetbeats]

In the service manual it looks like that guide is only attached by the screw.

Yeah, that's what I was thinking but I didn't want to suggest that for sure, not being able to verify on the machine.

Hmm...

Again, do you have the operating manual too? I'm wondering if that says anything about this issue.

The screw was probably tight due to loctite or equivalent.

Hey, let us know if you get a response from the Yahoo user group. The information would be good to have here.

Also, keep us posted on the follow up from RMGI.

I agree with above statements about that oxide shedding being way more than should be happening, and its happening on the supply side before the tape even has a chance to touch the lifters right (I thought there was a picture from below the suppy-side tension arm and the shed is all over the face of the deck right)?

What was the result of Beck's suggested test to run the tape from beginning to end in PLAY?

 

[nddhc]

The result of Becks experiment was a relatively clean tape path, however there was still some pretty noticeable dust all over the machine/table its sitting on. During rewind, oxide was getting sheared off the tape. This made me think the tape path was mostly to blame....


But then I just scored a great deal on a bunch of Quantegy 407 tape, not exactly the same type recommended for my machine, but its still 1 mil and to my ears sounds better than the LPR35 I was using, and so far I havent had any trouble with shedding or "shearing" during rewind.

Hmmmmmm.....
Im still waiting for replies from the Yahoo group so ill post any info I get here about alignment.

 

[sweetbeats]

nddhc,

Boy, I'd say by this time you've really given the RMGI tape a fair shake and it is not up to the task.

Again, yes, do post what you get back from the R8 group as well as from Phil Paske when he gets back to you.

 

[Beck]

The result of Becks experiment was a relatively clean tape path, however there was still some pretty noticeable dust all over the machine/table its sitting on. During rewind, oxide was getting sheared off the tape. This made me think the tape path was mostly to blame....


But then I just scored a great deal on a bunch of Quantegy 407 tape, not exactly the same type recommended for my machine, but its still 1 mil and to my ears sounds better than the LPR35 I was using, and so far I havent had any trouble with shedding or "shearing" during rewind.

I agree with sweetbeats. I'd say your test shows the LPR35 is the culprit, since you're having no trouble with the Quantegy 407. By the way 407 is one of my favorite tapes and is a good match for the R8. I also recommend it for the Tascam 22-2, 388, Fostex Model 20 half-track and Model 80 8-track.

It's a great tape and has the same bias as 457, which Fostex recommends for the R8. 407 is not quite as hot as 457, but it has a very warm, gentle compression compared to 456/457. Great classic analog sound. IMO, you scored big time with the 407.

 

[Latigo]

Hi. Does anyone here ever use the Geneva Trichlorotriflurothane head cleaner? Dad has used it on the Sony/MCI JH24 and the 1/4" mastering deck since the early 80s.
Does that machine your showing have a head tilt alignment on it?

Latigo