dc12

[johnner66]

print with cmyk dots on it what is the cause of it sometime after change new drum working fine sometimes after 1000 print cymk dots again thanks any ideal ,.,.,.

[GusG]

print with cmyk dots on it what is the cause of it sometime after change new drum working fine sometimes after 1000 print cymk dots again thanks any ideal ,.,.,.

I just had a similar issue on my DC12, little oval CMYK dots about 1 mm long that sit right next to each other and come on every A4 sheet, twice on A3 and shifting a millimeter or so between prints. On inspecting the drum there was clearly a little "hole' in the same size and shape as the dots. Changing the drum has eliminated the problem.
Do you see a mark on your drum where the dots come from? If so, perhaps something inside the printer is scratching or knocking against the drum.

[johnner66]

dc12

hi>thanks i have the same mark on drum but after changing drum sometime ok if lucky but some time change after 1000 print having the same is there any drum issue on it

[GusG]

hi>thanks i have the same mark on drum but after changing drum sometime ok if lucky but some time change after 1000 print having the same is there any drum issue on it

Something must be creating those marks on the drum, whether from within the machine or perhaps if you are taking out the drum and it gets knocked???

[xcopytech]

Main reason for drum dots is developer housing

remove developer housing and check it

[davidj7]

you could put an extra bearing on the developer housing to make it hitting the drum less frequent.