registration of the yellow rollers

hi again davor i do the registration again of the 3 yellow rollers form to the plate.
1. i do the 2 rollers form plate to 3-4 mm,and the third rollers that touch with plate at 2 mm but at the 3rd roller i see something wrong.this rollers dont makle an uniform line(or paralel) at the plate but left its less than 2 mm(lets say 1 or maybe 1.5mm) and right its ok and 2 mm.i cant do to registrate this roller.maybe i think its consumed or not? i set the temperature at 21 grade celcius but dont work again.have u any idea

 

Rollers adjustment

Hi Orange,

1st and 2nd inking form roller must have 3 mm line, 3rd 2,5 mm line. It is very important. Probably if you can not achieve those values - rollers must be replaced. I had many problems (very similar to yours) before changing rollers, specialy when printed sheet had high ink coverage.
If you see on checked line ends much wider value - this is an signal that rollers are old. Also for good ink flow is important pressure between rubber rollers and plastic rollers. If you buy new rollers buy it complete with new bearings. And don't forget to check lateral play after installing.
One of my friend who have QMDI also had problem with old rollers. In his case 3rd inking form roller was totaly invisible on plate (when setting screw was opened to maximum).

Davor

 

thnx davor for your help.today i am trying to put the yellow colour at the black section and the black color at the yellow .lets see whats happened.i have to see if its my foult of registration or not

 

back ground tintiung at yellow after 1000 paper printed

hi davor
i have 2 days that i do proves with rollers but dont work.yesterday and today i find something that i am in doubt.how is possible that the background tinting dont come when i print let say 100 sheets but appear after 1000 printed sheets.i am in doubt because if the rollers are not set correctly the print its not uniform lets say.so today i print 1000 sheet paper and then appears the backgroung tinting and not in first copies.how its possible this thing

 

If your number three roller is hollow shafted then ensure that its correctly sitting in its correct position via opertor side cover. Make sure retaining allen screw is secure.Check your roller with a vernier caliper for uniformity of roller. Finally after checking all your rollers are correctly set in roller train,make sure your offending roller is set paralell if its on an eccentric,you might have both sides set opposite to eachother when youve set your roller to oscillator

kev c

 

your rollers are set to plate with an allen key and is on an eccentric,make sure that you turn both adjusters the same way as it sounds that youve got the roller out of parallel.(askew)