KM FS-607 too much loop after conv roller 4, causing back edge flick

[raplma]

All, this one has me foxed, so would appreciate any suggestions.

FS-607 on KM5501, 3.3Mill finisher regularly cleaned and service parts within date.

If you are able to watch the short video clip below, you'll notice that as the sheet passes through conveyance roller 4, the back edge of the paper is flicking up, as the roller accelerates.
Curl adjustment has little effect and in any case if I remember correctly, that controls the speed differential between the c5501 exit rollers and finisher entrance rollers - hence loop production - rather than the side in question.
It is doing it on all lighter weight materials, the material being used is 130gsm, SRA4 coated gloss, and a quality paper.

The only thought that comes to mind is that the surface of the roller is causing adherence of the material??

More info: the observant will notice that there is the loom for the punch present. I noticed that the punch was jumping, so removed it and replaced it with the standard conveyance plate from a dead finisher.
However having done so I now know the jumping wasn't due to the punch but rather the 'flicking' of the back edge.

Any thoughts most welcome

[tsbservice]

Any paper jam code could be pertinent.

[raplma]

Totally agree, however there is no jam, it will happily run like this, it does not affect the functionality of the machine, so doesn't code out, it just curls the back end of the sheet like scissors curl a ribbon.

[tsbservice]

Totally agree, however there is no jam, it will happily run like this, it does not affect the functionality of the machine, so doesn't code out, it just curls the back end of the sheet like scissors curl a ribbon.

OK, any Mylar put on there or missing to prevent this? Must to admit,
I'm not familiar with this model at all, just working with you.

[raplma]

Indeed, your thoughts are most welcome.

The mylar guides are all present and in good condition. The conveyance roller underneath the grey one you see is in good order too, as are the mylar guides on the black plastic assembly it sits in. And certainly on other machines i have seen these guides well worn down, but on this finisher they are good. The lower roller is also sprung and this moves freely, so the tension between the rollers should be ok.

From your experience, could it be the grey roller has lost it's coating? Assuming it could be coated?? It is 9 years old, and from my litho days the surface of a roller is critical.

[Toxic]

Have that problem few times on C5501.
Paper come out ok but curly.
Problem solved replacing 13QE45132 CONVEYANCE ROLLER 3
Rubber rollers on the shaft gets lower diameter than normal and can not provide same paper speed like rollers before them and that is why paper go up and curly.
If i remember good,if half open CONVEYANCE GUIDE PLATE 5 while machine working thats disengage contact this problematic rollers on shaft with paper and paper go straight then like it should.

[blackcat4866]

Have that problem few times on C5501.
Paper come out ok but curly.
Problem solved replacing 13QE45132 CONVEYANCE ROLLER 3
Rubber rollers on the shaft gets lower diameter than normal and can not provide same paper speed like rollers before them and that is why paper go up and curly.
If i remember good,if half open CONVEYANCE GUIDE PLATE 5 while machine working thats disengage contact this problematic rollers on shaft with paper and paper go straight then like it should.

That was my theory right there. The reduced roller diameter would decelerate the paper. I don't know how much disassembly is required for this part of the machine, but I use a paper strip wrapped around the roller, then make a mark to determine the circumference. =^..^=

[raplma]

Have that problem few times on C5501.
Paper come out ok but curly.
Problem solved replacing 13QE45132 CONVEYANCE ROLLER 3
Rubber rollers on the shaft gets lower diameter than normal and can not provide same paper speed like rollers before them and that is why paper go up and curly.
If i remember good,if half open CONVEYANCE GUIDE PLATE 5 while machine working thats disengage contact this problematic rollers on shaft with paper and paper go straight then like it should.

Many thanks for this, makes perfect sense, will try this out and report back.
Thanks again

[tsbservice]

Have that problem few times on C5501.
Paper come out ok but curly.
Problem solved replacing 13QE45132 CONVEYANCE ROLLER 3
Rubber rollers on the shaft gets lower diameter than normal and can not provide same paper speed like rollers before them and that is why paper go up and curly.
If i remember good,if half open CONVEYANCE GUIDE PLATE 5 while machine working thats disengage contact this problematic rollers on shaft with paper and paper go straight then like it should.

They changed that roller also, new one is: 13QE45133E Conveyance Roller /3
Good call Toxic!

[raplma]

Once again I doff my cap to you, you're spot on
See the video below, placing a pad block behind plate 5 to take the pressure it exerts on roller 3 off, and indeed no curling, no flicking.
I've put an order in for the roller and indeed does not look the easiest to instal, but should be ok
Thanks again
Mark