Konica C8000 How to adjust image to Squareness

[[email protected]]

Hi,

We print with a lot of different stocks on our C8000 and every time we use a new paper we have to have a service visit
to get the image to print squarely as opposed to a parallelogram. While Konica responds promptly and squares the image, it slows us
down and we would rather do it ourselves if possible. Most of the time the two long sides of the image (18" side) are fine, but
the 2 other sides while parallel to each other do not meet the long sides at the proper 90 angle. Can anyone advise us as to how
this can be adjusted?

 

[rsands]

Do you perpendicularity? As in the bottom of the sheet is needs to move sideways to match the second side? The top matches fine but the bottom doesn't?

Richard

 

[KopyBoss]

Can anyone advise us as to how
this can be adjusted? - Under paper setting, select both sides, select tray to adjust, select chart adj., print chart, enter x & y values, select adj. start, go back to select chart adj., until complete.

 

[[email protected]]

Yes Richard that is it exactly and the problem exists with all trays equally, the procedure that KopyBoss mentions has been tried repeatedly and doesn't improve the lack of perpendicularity

 

[rsands]

We are having same issue but its not consistent. One minute its fine, next its not. Have you tried increasing registration loop?

 

[InvisSoul]

I'll tell you from my experience that we haven't touched the chart adjustment since they setup the machine. We have the same problem with it being on and then off slightly. If you adjust your backup (Both Sides adjustment) for that tray you can get it within a millimeter or two. Granted these machines won't be perfect on every sheet but you can get most things pretty close.

Also if you're using cut stock it may help to wipe the edges of the paper down to take off some of the excess paper dust. We run a lot of different stocks and this helped up quite a bit.

 

[rsands]

we going to ask enginneers to sort so will keep you posted. it needs that adjustment and reg loop seems intermitent as well

 

[rsands]

Ye we tried all of those. We had the machine printing face down, once we switched to face up the skew disappeared...so that makes me think the machine was flipping the sheet somewere and it was skewing?

Going to get engineer to show us the mechanical adjustments though. Kind of baffled as to why Konica don't offer a skew setting.

 

[csudman]

Mores shit KM expects you to accept "within spec". Eventualy, you just get used to crosshairs not lining up and hope your customers don't catch it.

 

[rsands]

Well i was told now "there is no mechanical adjustment". The sheet is sitting tight against the guides in the machine, no skew, the reg loop rollers are working fine. So its either enginer firmware or the alignment of the drums to the sheet could be out? Is that possible??

 

[KopyBoss]

Not sure why you put up with this. We have had our 8000's for almost two years and 6500 for five. KM knows if we have a problem they are to fix it thats why we pay for service. I don't put up with there crap about it's in spec or this or that, I'm professional with them, but they know I will tell them to take there equipment out in the drop of a dime. We were all Xerox Color & B/W before switching all color to KM our volume is very high and Xerox is always on us to switch color back to there equipment. Bottom line I told KM if the machines are not running no one is making money and if there techs cannot keep us up I would go to a vendor that can do the job. I have had them switch out engines on both equipment in the past. You have more power with them than you know just have to use it. There are a lot of print for pay shops they went under and these companies are fighting to hold on to the ones that are left who do a large volume.

 

[ColorKeyOp]

We have three 8000's. We dedicated certain trays on each machine to certain sheet sizes, and switched out the little blue tab/screw thing for a metal screw. This locks down the trays to 12x?, 11x?, etc. Greatly improves registration.

 

[csudman]

Well i was told now "there is no mechanical adjustment". The sheet is sitting tight against the guides in the machine, no skew, the reg loop rollers are working fine. So its either enginer firmware or the alignment of the drums to the sheet could be out? Is that possible??

What ended up making the most difference for us was actualy the alignment of the large cap trays. I made my tech work for 2 hours shifting it back and forth till we couldn't get the registration any tighter. I can say, I have NEVER seen loop adjustment have ANY impact on skew or anything else for that matter.

Not sure why you put up with this. We have had our 8000's for almost two years and 6500 for five. KM knows if we have a problem they are to fix it thats why we pay for service. I don't put up with there crap about it's in spec or this or that, I'm professional with them, but they know I will tell them to take there equipment out in the drop of a dime. We were all Xerox Color & B/W before switching all color to KM our volume is very high and Xerox is always on us to switch color back to there equipment. Bottom line I told KM if the machines are not running no one is making money and if there techs cannot keep us up I would go to a vendor that can do the job. I have had them switch out engines on both equipment in the past. You have more power with them than you know just have to use it. There are a lot of print for pay shops they went under and these companies are fighting to hold on to the ones that are left who do a large volume.

You say "why we put up with this" PLEASE tell me what else I can do. They know we want them to buy out our lease. It makes no sence for them to do it, KM doesn't hold the lease. They've replaced the main engine once for a "like" machine from a demo room. We were professional and VERY patient, that didn't work and we weren't getting our issues resolved. I went to the brains at printplanet for help and caused a PR shit storm for KM(that wasn't my goal). But that hasn't fixed it. We're back at the point of patient and pleading for a fix. They are working on it is what we get. But never a full final fix.

We have three 8000's.

I'm sorry

 

[rsands]

Well after alot of fiddling we got there....service manual is the best pdf made!

A full understanding of the machine and its functions, paper paths, rollers, etc meant we adjusted a good bit and got it back into square. Now its holding 100% and giving no problems at all. Got the skew back inline and sorted.

CD Mag Skew Adj is a big one
then pre reg loop
then reg loop

Turn off auto centering and get the side 1 in line. Then once side 1 is in the middle ( CD Adjustment if i remember right) turn auto centering back on and put side 2 in line. With auto centering turned off it meant the machine wasnt trying to center the sheet - we were using mechanical adjustments to get the side 1 in line first

 

[Toner4Brains]

I was operating under the assumption that FD/CD-Mag are set up properly when chiming in on this, I apologize for jumping ahead when I responded above.

Something to point out that may need clarifying for others that run into this thread - registration loop and skew detection both address *paper* skew, not optical skew which is what CD-Mag Skew aligns. Without CD-Mag Skew dialed in, your starting point would be a parallelogram and even if your paper is traveling straight you will see skew when toner hits paper. Any mechanical adjustment to skew detection like I referenced above as well as registration loop adjustment would be for paper physically skewing through the transfer path.

CD-Mag (Cross Direction Magnification) and FD-Mag (Feed Direction Magnification) baseline image centering and lead edge timing respectively, which are the reference points the active registration system uses to properly place the image. Without these properly dialed in, the image frame is placed (and adjusted against) disproportionately to the lead edge and center of the sheet.