TASCAM Porta Two - tape bunching at pinch roller. Takeup reel issue?

neckcarpenter

New member
I've just found a deal on three machines: 2 Porta Two's and 1 Porta One. Of course, none of them are fully functional, but the hope is that eventually, one of them will work, so I'm messing around with the Porta Two that is the most promising of the group.

The only thing in the way of this being reasonably functional is that tape bunches at the pinch roller/capstan zone. More specifically it feeds through the pinch without being tangled but then bunches just to the right of it.

The culprit appears to be that the take up reel doesn't spin. Well it does, but very slowly, and haltingly. Not nearly fast enough to reel the tape as it plays. I've already opened up the machine and changed two of the three belts, which I believe included the belt that controls the take up side. I didn't change the large, flat capstan belt. Changing the belts hasn't improved it at all.

When playing a five second tape loop tape, everything is fine, probably because the loop doesn't require any take up.

Any ideas of what I'm doing wrong? All help is appreciated!
 
I would be surprised if the reel tables are activated by a belt at all. Usually it’s a gear-driven idler with a rubber tire on it. So you should see if that’s the case and check the condition of that tire. Another issue that can come up is the lubricant on the spindle upon which the reel table spins can become dried out and tacky. Best practice is to disassemble, clean, and conservatively relubricate with Lubriplate 105.
 
Thanks Sweetbeats!
Here's what I see when I remove the black reel plate from the transport assembly.
Is that idler tire troublesome? I can't tell just by looking at it. I cleaned and relubricated what I can see, *while keeping this whole thing intact*. Mainly because I haven't figured out how to disassemble the take up reel/idler section further. But I'm starting to think I should learn how...

What I do know is if a little bit of force is added onto the tire/reel point of contact (either by pressing down on the tire, or left on the lever it's connected to), then it drives the take up table much more reliably. Does this mean it's worn?

blackplatefrontidlertire.jpegblackplateback.jpeg
 
Here's the point of (non) friction between the idler tire and the take up reel.
idlertirefrictionpoint.jpeg

Quick googling shows that someone is selling tires for the Porta One, and a bunch of other machines, but not this one!
A youtuber made a new one out of a couple rubber plumbing washers, for the 244. I love the inginuity!

Porta Two is sadly not represented in the DIY idler fixing scene.
 
Ive found in many machines that to be an idler tire symptom. Its a good idea to replace all rubber.

Sweetbeats made a good point about the lube drying out.
 
Fixed, with a caveat!

I removed the idler tire/arm assembly (by lifting that little white plastic pin/cap thing to the left of the tire) ,cleaned, lubed, and then...kinda improvised a fix.
I took off the tire from the wheel, spooled a bit of thread around the wheel and put the tire back on. It's working wonderfully for now.
This only worked because the rubber is in decent condition, certainly better condition than the disintegrated or chewed up ones I've seen on youtube.
Not a permanent fix, but it's great to have this one working for now to at least test record functions and such.
 
I suspect that you have a take-up clutch issue rather than a belt issue. In the recorders which I have opened up, the actual "hub" which engages with the take-up reel in the cassette is connected to a spinning disk by a clutch. If the tape is bunching up after the capstan, then the take-up clutch is apparently slipping too much to turn the take-up hub fast enough to keep the tape at the proper tension after it leaves the capstan. I have found that those clutches are difficult to adjust if adjustment is even possible. If you have the service manual for that recorder, you might find information there regarding any adjustment that is possible.
If you can put the transport in motion without a cassette in place by somehow "cheating" any interlock on it, you might get a feel for take-up tension by holding the take-up hub as the machine pull against your hand. Since you say that it spins but very slowly, you might observe that the hub tension varies as the hub rotates through its 360-degrees of rotation.
Since you have altogether three of these machines, I suggest "knobman's knobby approach" as a possibility. If one of your "dead" machines still has a good take-up assembly, you might swap that assembly with the questionable one in the unit you want to save. If you can do that, you might solve your take-up issue.
If parts are still available for that machine, you might order a spare take-up assembly for it. To do that as simply as possible, you will probably need the service manual so that you can try to request the proper part number. Quite often, you cannot obtain a replacement part without the part number, the model number, and sometimes the serial number, chassis number, and the last four digits of your Social Security Number - well, ok, it isn't quite that bad; but because parts sometimes change within the same model, they might ask for a serial number.
I hope you are able to fix the "good" recorder by swapping out the questionable take-up assembly. Concerning belts, I doubt that there is any way to adjust belt tension on one of these machines unless they are using a spring-loaded idler to maintain belt tension; but offhand, I doubt that the belts are slipping to cause your problem.
 
Thanks for the info, hautbois!
If you look at post #6, you'll see that it was an issue of the idler tire not having enough contact with the take up reel. I worked out a solution, and it's still going strong!
 
I'm glad to hear that you have a fix that is still working quite well. We often have to improvise in a world of planned obsolescence and throw-away hardware. I was also interested in learning how that recorder's transport is made, since the cassette decks I have opened up had the clutch assemblies which I mentioned. The old Sony 105 open-reel recorders had a similar clutch setup on which an idler/belt arrangement spins a "table' on which the takeup reel sits. Very interesting, and I am glad to know that your system is working well.
 
I wouldn't pay more than $140 or so for one of these with this issue.
The scary part of course, is all the other stuff that might also be wrong once you have it up and running and testing.
 
I've fixed this issue on another deck by sanding down the idler tire just a bit to get to some fresh rubber again. It worked like a charm.
 
Back
Top