Tascam 32-2B Tension Arms stiff and lever arm foam stop deteriorated

[Compton]

Hi.
I am looking for advice to get my Tascam 32-2B (owned from new circa 1982 approx and recently out of 15+ years dry storage) up and running. Please note that this is the machine with an analogue (belt driven) counter and adjacent timer start function button. It is not the newer Tascam 32 with digital counter and return to zero function.

I have had the drive belt changed by a professional engineer who also said he serviced the machine. The machine is running (the transport functions are all working) but there are issues not addressed by the tech. It is impractical due to distance and cost to re hire the tech.

The issue is that the tension arms actions are both stiff and jerky (not smooth). The action is smooth at the lower part of the arm travel but stiff and jerky as tension is applied). I have removed the casing and following advice on this forum waxed each tension arms string. This has helped (it is now smoother but not super smooth. (I have not yet tested with tape) In doing this I noticed that the small foam slotted block the tension arm lever touches (or passes through) at the top of the tension arm lever travel has deteriorated (it is no longer springy) This is the same for both arms. Would renewing the foam slot (so it acts like foam should) (be a cushion) make a difference to performance?

The big picture is that the machine is working mechanically but the recording function is problematic as the tape is not held firmly against the heads in recording or playback mode. So far I have cleaned everything accessible on the outside of the machine which has improved matters but not solved the tape not fully keeping in contact with the heads. Before the clean the tape was also moving up and down as it passed over the heads. This is now improved but the tape seems (is) somewhat loose it passes over the heads so that it can flap (not be in constant contact with the heads). At this stage given that the tension arms were stiff and jerky (not smooth) I decided to investigate if this may be the problem. (Note that during the clean I also cleaned the rubber rollers and applied renovator.)

I have (following the service manual instructions) removed the machine from the case allowing access to the workings of the tension arms mechanisms. As mentioned above I have applied candle wax to the string and also the plastic (non rotating) guide.

Any thoughts , opinions or advice to improve the tension arms performance and the deteriorated slotted foam block and solve the tape not being in consistent contact with the heads will be gratefully received.

Please see image of one of the tension arm mechanisms and an image of the heads.
https://www.dropbox.com/s/pao98mtaa52cvea/01_Tension Arm Mechanism.jpg?dl=0
https://www.dropbox.com/s/zpzi1ju3hhnbeju/02_Heads.jpg?dl=0

 

[SkywaveTDR]

There are a lot of people that call themselves Technicians or even Engineers and do not know the first thing about some of the stuff they tackle. If a guy worked on the unit and the bumpers and tension arms do not react as they should get rid of that guy. I change the bumpers with a Neoprene foam like what I put on X1000R and X2000R tension arm bumpers. This keep the arms from going all the way up all the time. The tension arm roller are on levers that have a pivot rod. Did he take and oil those? Probably not. The 32-2 is a 1/2 track version of the X10 Transport. The correct belt needs to be on the unit but even more importantly is the required oiling of the capstan bearing with AMSoil and I mean with the capstan shaft out of it.

The heads as the wear happens wear down so that the original tape path is receding. What I do is move the heads up so they have more penetration to the tape path which improves the tape to head contact. The tape from start to stop should always be in contact with the heads unless the lifter pulls it away. In some decks I have had to drill and slot the head mount a little bit that requires the removal of the head and then when the heads are moved up and mounted correctly with tangency correct then they work much better. Good tape to head contact is important and another thing I found that helps improve this once the heads have good contact is the car polish Nu Finish. It leaves a surfactant behind that lubricates the tape path and improves tape to head contact. I found this true even on a model called the 42. There is a reason the deck work better when from the hands of an experienced Technician who has worked with these over the years- I started my work in 1982 at Teac in Arlington Heights. You will tell the experience of the guy who works on a deck by the results he obtains. many local shops are hacks and amateurs even though they charge money for it. Russ Bachmann is in New Jersey- the last manager of that facility. I was from the Chicago branch and Jim Finch is in WA state now. Some trainees of mine might be helpful but in some cases you need the experience that comes from years of working on the stuff.
Also note that some answers can also be found at the Reel to Reel Clinic on Facebook. I am there as well as Jim.

 

[Compton]

Thanks Skywave for a detailed response.

I only hope the engineer at least fitted the correct belt. I will try to find out if he oiled the capstan bearing. I am UK based and it seems I chose the wrong engineer

Did you make your own bumpers with a Neoprene foam?

When you mention applying NuFinish to the heads would this be after cleaning with Isopropanol?

The other problem I am having is gaining access to the brakes. I have the back casing off but this does not give access to the brakes and I cannot find any info in the manual for removing the front panel. Would you know if the front panel is (meant to be) removable and any tips do do so would be welcome.

 

[Compton]

Having lubricated (waxed) the tension arm strings I have tested the machine with tape. Unfortunately, the same tape path problem persists. Does not record consistently and the tape moves up and down (oscillates) across the heads and RH side pinch wheel. I have not yet projected the heads forward as Skywave has suggested. Before I go down this path I have prepared a short video demonstrating the current situation.

Here is the link to the video
https://www.dropbox.com/s/pp3tfm2okqun7et/32-2B_Tape Oscillating Across The Heads.AVI?dl=0

Any further ideas will be greatly welcomed.

 

[SkywaveTDR]

You have tape skew and this has nothing to do with the heads. Do not move them until the tape path is stable. In the X2000R deck I did have a skew problem that I worked on for hours then I found out that due to the stupid and wrong way they mounted the heads, that the skew was caused by a tilted head. I straightened it and the skew went away. Now the X2000R has back tension and forward tension adjustments being a servo deck but the X10 and 32-2 do not have this. Still as I seem to recall the back tension on a X10 reel deck as measured with a Tentelometer was about 70g/cm. I would tray some different pinch rollers first, then after that check the meet up contact point and I do this with bright light and a business card so that between the capstan shaft and the Pinch roller the small crack visible should be in the center not one side. Add a little back tension with hand on the reel and see if that helps- just a little not heavy retarding of the reel.
The design of the X10 or 32-2 was not well though out with regards to brakes. In the one time in my 47 years I had to deal with a new brake pad on a brake band I did have to take the face panel off and this is something I do not want to do as there are springs attached and it is really an insane way to access the brakes but seems to be the only way. Do not stretch the springs and they are glued down with rubber cement so some Lacquer thinner might be needed to soften that glue to remove the springs.
Isopropyl alcohol here is used only to clean PCB not heads. The solvent I use is Denatured alcohol and I have seen decks come in that did not record at all because the cleaning was done with Isopropyl alcohol. It does not do the job. Nu Finish is used to polish the heads allowing the surfactant to get into the metal and then clean off with denatured alcohol just to remove the ceramic material.

 

[Compton]

Hi Skywave TDR
Thank you so much for taking the time to provide your detailed response.

I have now swapped round the pinch rollers and the tape skidding has gone. The machine also now records and plays back at both speeds (15 and 7.5ips) but not well compared to the input signal. However, when I fiddle with the tension arms the recorded sound improves (gets louder matching the input signal). Compared to the input signal the recorded signal is quite muffled (no crisp high frequencies) and I am hoping the heads cleaning as you suggest may improve things. Do you clean all the metal parts with NuFinish and Denatured Alcohol or only the heads?

Any tips you may have to adjust the tension arms will be welcome as the action is still not smooth. I will try out the other procedures you mention and hopefully improve things further.

Can you let me know if denatured alcohol is the same as Ethanol Denatured Alcohol as per this link.
https://www.amazon.co.uk/ETHANOL-De...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

NuFinish seems to be unavailable in the UK. I have found it on Amazon but for a cost of £50. Do you think that another of these Amazon advertised car polishes would do the same job.
https://www.amazon.co.uk/s?k=nufini...ix=NuFInish,aps,218&ref=nb_sb_ss_ts-doa-p_1_8

With grateful thanks
Compton

 

[SkywaveTDR]

The orange bottle of Nu Finish is the only product known to have the OAD surfactant in it that works. Others may have other chemicals but these are untested so you would have to experiment. I Nu Finish heads mostly and anything that would benefit from better tape travel that is like a tension arm with stationary pin that has flat spot due to wear. Ideally a tension arm could have a ceramic post fitted so that the wear is a lot less and the material has less friction but they cost more to make. The Alcohol I have used for 47 years is that which you get in the paint isle of the hardware store. It is nothing fancy. The reason people use Isopropyl is that they get it at a drug store and it can be only 70%-90% but the chemical with water in it and also some smell added is not made for heads but skin. If you get the lab grade stuff like I have it works just as bad so there is no reason to use it.
On the audio section of the deck you need to detect if there is a back tension problem or a tape path alignment problem- Tension roller depth can be adjusted but some that do it are not watching the stationary guides and causing curl that then skew the tape and then it can wonder off the pinch roller due to a S curve tape path. This is what happens when people touch things and they do not know what they are doing. There are also reel motors that lose torque due to carbon build up in the commutator and this needs to be taken out and cleaned. The way you find out if the tension is wrong is with a tension gauge like a Tentelometer. Too many people guess and take a lot of time doing the wrong things. Many problems are observe and take the right action but what the right action is is different based on a persons experience. A way to measure the tension and a known value on a good machine is something to know. As guessing at a solution often times does not work as they are going in the wrong direction. Back tension in a deck is NOT always the right solution to a problem as it fights the capstan motor and increases wow and flutter. It is suppose to be a certain value and not more. See if there is curling at the entrance guide of the head block- if so correct the roller guide depth so that the curl goes away- it does not belong there regardless of tape skew or not.
If heads have a significant amount of wear then they might have to be moved up as the original tape path was designed for new heads not worn ones and so as wear happens it is the seasoned Technician that then has to take action to correct for the head surface to be further back. This is what moving the heads up helps provide. There is a lot of other things going on as Tangency so we are not dealing with a part that just moves and is OK. You need to have a test tape that will allow one to maximize a optimum head position. I made one at 16KHz that tells me if the head is in the right position and god tangency as when you get every last dB of signal off a head, this is the best position it can be. If it is so worn that it can not make specs then it needs to be replaced.

 

[Compton]

Thanks Skywave for very detailed information.

I have found a UK source of NuFinish so will give that I try when it arrives. (It seems that Denatured Alcohol is know as Methylated Spirits in the UK) (readily available in paint stores)

I now have the machine working well with small reels. A recorded signal plays back and sounds close in quality to the input signal. However, it is not so good with large reels as the signal fluctuates but can improve if the tension arm on the feed side is played with.

I have lubricated the sprung spindle on the tension arm mechanisms and this improved recording with small reels. As mentioned above not so good with large reels.

I do not have any tape curling.

At the moment when I go in to play both the tension arms go to and stay at the top of the slots (large and small reels) regardless of where the tape is being played from (beginning / mid / end of a reel). On rewind and fast forward the arms adjust continuously around the central area of slots and differentiate depending on the tape spool position which I think is what should happen.

I notice with that at the top of tension arm mechanism there are a number of alternate slots for retaining the main spring as it points upwards from the spring retaining screw. Please see image of the mechanism. Do you think trying different spring retaining positions will make a difference to the performance of the tension arms.
https://www.dropbox.com/s/pao98mtaa52cvea/01_Tension Arm Mechanism.jpg?dl=0

 

[SkywaveTDR]

Well the spring position does affect the tension arm position but it can also cause the deck to turn off as the arms in some cases get pushed down too far. Large reels with the larger diameter hubs will have less torque than smaller ones. So it is more likely that you are having less tension than what should be. A X10R owner that replaced brakes on a deck also found that when he replaced electrolytics on the board if fixed his brake sloppiness. Well the brake sloppiness was actually when he improved the torque control. I asked him which one were the cause and he said he changed them all on the control board. I think you are going to have trouble fixing this if you don't have a way to measure the back tension and then make changes and see if it goes up. For bumpers I bought a strip of weather strip from Mc Master Carr that was the thicker dense foam and all you need do is cut the size you need with scissors. It has it's own adhesive and if you but 1/2" tall it van be trimmed down but I put put the 1/2" stuff in and it seems to work well. The manual says in it that small reel back tension for a small reel is 18 plus minus 40g/cm while the large reel is 300 plus/minus 40g/cm but these are values using the reel and string method in the manual not a Tentelometer.

 

[Compton]

Thank you again Skywave for taking the time to respond in detail to my issues.

In respect of the tension arm mechanism main spring. I have tested in the two alternate slots for the upper part of the spring. It makes a noticeable difference. In the position nearest the side casing (both arms) the tension on braking (stopping the tape or going straight to play) from fast forward or rewind drops the arms too far and the tape needs to be manually wound enough to start the motor. However, in the alternate position (the slot most inward from the side casing) improves things noticeably. (Stopping or going straight to play from fast forward or rewind at any point in the tape) Recording with large reels at high speed is still not reliable. However, if I lightly push against tape from the feed reel (before it reaches the tension arm) recording is much improved. As an alternative to lightly pushing against the tape while recording I push up lightly on the LH pinch roller I get the same improved recording result.

Given that to get this far I have needed to swap the pinch rollers around I have come to the view that replacing the pinch rollers is probably my next best option and if the recording performance with new pinch rollers is improved I will have the option to return the spring to the original centre slot if needs be.

I also intend to make the tension arm boots as you have explained and polishing and cleaning the heads as you recommend.

I am very grateful for the detailed explanations you have provided which have been a great help to me and I hope others.

Many thanks,
Compton

 

[SkywaveTDR]

If the increase in upward pressure on the left pinch roller happens that would make me think the pressure is not right. With a 10.5" reel on I would adjust the pinch roller pressure nut the one in center with a 1KHz signal recording on tape. If a 1/2 turn or so causes the recording to be better leave the nut there. If no different then turn back. The rubber bumpers on the linkages make little difference as they may be there for noise mitigation. In all the deck I have worked on I get the linkages working well and never touch those. The bumpers that are at top limit of the tension arms are changed a lot as the foam they used seems to turn to powder- care must be taken when removing this as black residue can drop down into meter area and drive you nits looking at it. I usually put a business card or other piece of cardboard under the bumper when I remove it as always some parts drop down that would be powder residue. I have not had any bumpers I have put in fail so far but maybe in 10 or 20 years. I will have new stuff here if I am still around working on these.

 

[Compton]

Hi Skywave.
Thanks for the info.

I have made the pinch roller pressure adjustment as you suggested with a large reel at 15 ips. This has made a great improvement. I now have the machine useable at high and low speed with small and large reels.

If I record (no signal) over a recorded section of tape there is some faint bleed through from the previous recording but I am hoping this will be due to head cleaning. I am waiting for the right materials for cleaning as you suggest.

The only issue now is if I use the switch option for small reels. Using the large reel setting for all the testing (7.5 and 10 .5 reels at high and low speeds) all is now working good. But pressing the small reel button results in non or spasmatic recording. I can live with this and maybe when new pinch rollers are fitted this will solve the issue.

In testing with a music track using the Tascam as a tape delay at 15 ips it is really good for thickening vocals. Much better than a delay plugin (Logic Pro X) . The vocal sound off tape when mixed with the original signal is a very real sounding auto double track (vocal thickener) and does not sound at all artificial. (Analogue lives !!!)

Thanks again for all your advice and detailed explanations which has led to a now usable machine from an unusable machine when I first posted my issues and I have learned a lot on the way.

Compton

 

[SkywaveTDR]

Goof for you. Sometimes it is the small adjustments that make a difference. The reel size switch issue might be failing caps in the control board. That deck is approaching the time when they should be changed. I had some X10R decks that I ended up putting larger caps in some section and also added to some filter caps. They had complaints of slow wind on decks like the X7 but when I made a mod to switch in the right voltage only in fast wind the reel motors took off. A 3 minute or greater 1800 foot tape could be wound in 57 seconds but I cut back as that is a little too fast. Some looking into the back tension amounts for that deck might be needed.

 

[Compton]

Hi Skywave.
Just a quick update.

I have now used Nufinish and denatured alcohol (methylated sprits in the UK) to clean the heads and metal parts as you suggested. This has resulted in a noticeable improvement in sound quality and solved the erase bleed through issue Also the transport is now smooth and noise free (no little rattles and noises).

Thanks again for all your assistance.

Compton

 

[SkywaveTDR]

Yes, These decks can work again with the right amount of effort and use of right chemicals.