Riso RZ970 Paper Jam on printing area, every time

[thibaut]

Hey !
New thread about my super RZ970 which has a real big problem of timing (I had started another thread on a problem I have also with this machine : the masters don’t eject from the drum). I even had to change the TM for positions A and B. And it works ok (except for the master eject part).

But, all brand new. Since yesterday I had a singular paper feed problem, with paper stuck halfway in the machine (a bit is still outside). EVERY TIME after the making of a new master.
I have found this old thread where the OP post youtube link with EXACTLY the paper jam I have : RP3700 Paper Feed Issues

The problem was just keepin’ going and I could not print.
After many checks around the paper feed section, I went into the TM and make some tests with an history of the errors. The most recurrent error is A07-410 : Paper-ejection sensor was OFF when paper should have arrived, and the paper sensorwas OFF when the machine stopped (paper jam on the print drum).
So I tried to modify some TM to delay the OFF timing. Like TM742 (Paper-feed-clutch OFF angle ), TM748 (Scraper Clutch OFF Angle), TM753 (Paper receiving jam detection angle. (Paper IN)), and it seems (for now) to work, EXCEPT after the making of a new master, it paper jams every time.

I have to say I guess something is around a bad timing on the machine. But if you have some guesses... I just feel my parameters adjustments are not a long time solution.

Thanks!

[Paco Telescopios]

Hello,

Please excuse my bad english.

I had this problem in my Rp3700 some weeks ago. The pickup roller and the feed roller took the paper ok, then it seemed to stop in the second feed section which caused it to bend, and then a jam error.
It happened only at the reversed face with a light type of paper that previously had worked without any problem (+400 sheets printed one face)

Adjusting the first feed section did nothing; it worked ok
I seemed a problem of paper detection, but test said ok. I cleaned the paper sensors with no success
Check timing and seemed ok (maybe not, I'm new here. I have a foto somewhere...)
Even played with the adjustment of the double feed detection.

It came to my mind (I read it somewhere, I suppose) that the timing adjusts itself in some way with the feed speed, so I try this and the problem disappeared... just pushing the feed speed from minimun (my defaul then) to one step more!
I've not used this paper since then, but no problems with the others in this speed.

Not a very cientific approach, but hope this helps

[thibaut]

Hey, that’s a good idea !

Just one question to be sure: You’re talking about the feed speed parameter buttons on the machine, right?!
I think that’s an idea, as the problem got something to do with the timing of the sheet into the machine!
Will try that today, right now.
No scientific but if it works...

[Paco Telescopios]

Thank you,

Yes, just the speed buttons in the machine.
I also thought it to be related to the timming, but checked it and seemed ok (I could be wrong, no experience)
I examined the options in TM and was afraid of getting it worse, je.

In my case, the sheet after master went always ok, and I realized that by default it was setted at speed two, but after the master was made I used to lower it.
It is a very silly thing, but raising the speed seemed to work for me.

Good luck

[thibaut]

Thank you,

Yes, just the speed buttons in the machine.
I also thought it to be related to the timming, but checked it and seemed ok (I could be wrong, no experience)
I examined the options in TM and was afraid of getting it worse, je.

Ok, I’ll try that ! It drives me mad that the sheet after the master always made this A08-410 error, related to the Paper-ejection sensor !
And yes, you’re right : dealing with the TM timing settings is not recommended, everybody here gave me this advice
I unfortunately MUST change them in order to have a good position B and A for my drums so...

In my case, the sheet after master went always ok, and I realized that by default it was setted at speed two, but after the master was made I used to lower it.
It is a very silly thing, but raising the speed seemed to work for me.
Good luck

Ah ah, right now, to avoid the same paper jam occurring during « normal » printing i lower the speed. I just tried again : It does not work.

More : To print correctly after the master is made (and the first inevitable jam), I have to LOWER the speed at the minimum.... Otherwise, it just jam !