JFX200-2531 print quality issue

[woody1512]

Good morning all, as you can see i have an issue with print quality (flatbed 1 image). we have replaced the encoder (this was needed anyway) but the issue remains. the red arrows where the issue is on print (NOT PRINT DIRECTION)
(flatbed 2 image) shows the print position on the flatbed. if anyone has any ideas, I would be grateful. A call has been logged. thank you

 

[guillermo]

looks to me that that area is a little higher than the rest, but if this is not the first one, check under the print head, some times, dirt is accumulated and causes to touch material, but is strange that only in that area.

 

[Smoke_Jaguar]

Might want to run a bed thickness check. Acceptable deviation across the entire bed is 0.4mm, but with time and some Allen wrenches, can get that down to 0.1-0.2mm easy.

 

[woody1512]

looks to me that that area is a little higher than the rest, but if this is not the first one, check under the print head, some times, dirt is accumulated and causes to touch material, but is strange that only in that area.

Thanks this was the first thing I though to be honest: print heads are clean as well as the head guard and lamp glass. numerous head height checks show 0.2mm difference across the sheet. we tried different brands of Di-bond and different batch numbers with no change. we have had a new encoder installed and there is still no change. the photo does not do it justice. it covers the whole sheet pretty much sometimes more obvious than others and certain angles under light show it. very difficult to see with this image when flat on the bed.

 

[woody1512]

Might want to run a bed thickness check. Acceptable deviation across the entire bed is 0.4mm, but with time and some Allen wrenches, can get that down to 0.1-0.2mm easy.

thank you Bud, engineer who replaced our encoder checked the bed it was 0.2mm deviation, he said this was fine and within parameters for the machine.

 

[guillermo]

also, check for accumulated in when printing beyond the substrate, that little ink will make a change specially if the material is hard, like dibond.

another trick, if I suspect that there is uneven material, I check thickness in 5 points, center and middle of the center and left, right top and bottom, and choose the highest one.

 

[woody1512]

Good morning all, as you can see i have an issue with print quality (flatbed 1 image). we have replaced the encoder (this was needed anyway) but the issue remains. the red arrows where the issue is on print (NOT PRINT DIRECTION)
(flatbed 2 image) shows the print position on the flatbed. if anyone has any ideas, I would be grateful. A call has been logged. thank you

UPDATE: we have had both heads replaced (they were starting to de-laminate) so far prints have been ok but i have another 120 panel job coming up shortly so that will be the big test. Thank you all for your input and advice.