HP Latex 365... Anyone know what causes this?

[FearinLoathin]

We've been coming up with this streaking when we do long runs, and it particularly seems to affect the black. It's happening when we print perf, regardless of the manufacturer. This is the Briteline 60/40, run at "Max Black" CMYK (all four at 100%).

Profile is a custom one I created from the Grimco stock perf profile, I just upped the passes to 12 and lowered the temp to 190, both adjustments based on what I've read on this forum. It started out printing just fine, and when I rolled out the panels to check the rest, it gradually fades out as the roll goes back in time.

I figure this is the best place to get answers (actually I know it is, apart from HP themselves), so if anyone has sorted this issue out, please advise. Thanks in advance!

 

[FearinLoathin]

Ok, scratch that, it ran through the whole damn print... I kept a close eye on this run while it was printing and this was not present as it was coming off the printer and through drying. It's almost like it's a material defect, but we had the same thing happen on a 50/50 we used previously.

That said, it does gradually get worse as the print continues.

 

[Geneva Olson]

looks like it's not quit up enough to be a head strike. Is the ink dry?

 

[FearinLoathin]

We think it was just too much ink... We changed the black to just 100% K and it seemed to work it out. Appreciate the response though!

 

[MikePro]

was gonna say, sounds like a lotta ink
my deepest blacks are usually in the 100K 10-30cmy range.

i get vertical streaks in perf prints when the material slightly buckles from the heat though, usually remedied by dialing-down the preheat and setting up the tension bar & takeup prior to starting print.

 

[Pastie]

We do 100 40 40 40 for our super blacks.

 

[Brian2345]

We've been coming up with this streaking when we do long runs, and it particularly seems to affect the black. It's happening when we print perf, regardless of the manufacturer. This is the Briteline 60/40, run at "Max Black" CMYK (all four at 100%).

Profile is a custom one I created from the Grimco stock perf profile, I just upped the passes to 12 and lowered the temp to 190, both adjustments based on what I've read on this forum. It started out printing just fine, and when I rolled out the panels to check the rest, it gradually fades out as the roll goes back in time.

I figure this is the best place to get answers (actually I know it is, apart from HP themselves), so if anyone has sorted this issue out, please advise. Thanks in advance! View attachment 177506

We just got a bad roll of Perf from Briteline, its probably the media. This has happened three times in 2 years for me, but it always happens at the damn worse times!

 

[citysignshop]

We think it was just too much ink... We changed the black to just 100% K and it seemed to work it out. Appreciate the response though!

I find 100K much too 'grey-brown'.....and need SOME of the CMY to darken it to true black! surprised this works for you.
Re: the striping....looks mechanical, either in YOUR machine, or BriteLines'. You say this happened on the 50-50 perf, was it in the same spot?
I'd guess they have a roller in their equipment that's contaminated with silicone lube or something....and your ink won't lay down nicely in that area.....
Lighter coverage hides it, but when loaded up with your 100-100-100-100 flood of ink, it shows up.
...but hey, just some armchair quarterbacking here, I haven't played much with profiles on our 365 to know the finer details.

 

[FearinLoathin]

I find 100K much too 'grey-brown'.....and need SOME of the CMY to darken it to true black! surprised this works for you.
Re: the striping....looks mechanical, either in YOUR machine, or BriteLines'. You say this happened on the 50-50 perf, was it in the same spot?
I'd guess they have a roller in their equipment that's contaminated with silicone lube or something....and your ink won't lay down nicely in that area.....
Lighter coverage hides it, but when loaded up with your 100-100-100-100 flood of ink, it shows up.
...but hey, just some armchair quarterbacking here, I haven't played much with profiles on our 365 to know the finer details.

Thank you for your reply. We discussed that it could possibly be an inconsistency in the dryer, because it is consistently in that area and the same "pattern" every time. I did a test print of about 4" of black all the way across the film, using different mixes of CMYKcm, and the heavier ink applications came out with the streaking in that area. I hit it with a heat gun as soon as I pulled it off the printer and the streaking didn't disappear, but there was an obvious change in the appearance.
I like the suggestion of a contamination on the rollers, we will check that out! I'm still sorting through comments but really appreciate the suggestions.

Edit: I also agree that running just the K at 100% doesn't quite create that richness you get with a dash of the others added in. Great tip!

 

[balstestrat]

When was your heater cleaned last?

 

[FearinLoathin]

When was your heater cleaned last?

That's a great question... I have no idea. There's a possibility it has never been cleaned! I'll look into it, thank you.

 

[balstestrat]

That's a great question... I have no idea. There's a possibility it has never been cleaned! I'll look into it, thank you.

If you've ever had SMK#3 service done on it, it should have been taken out on a table and done.

 

[FearinLoathin]

Gotcha. I've only been with the company since last July, so I don't know if that's been done. Doubtful, honestly.

 

[guillermo]

Did you use the take-up reel? it happened to me when I did a long run and did not use the take-up reel, that will help to keep the material flat under the heater, sometimes when there is not pulling down, it will touch the heather, upper side and cause that.... and there is a setting when you add a material that says, optimize or keep consistence for long runs.

 

[MNT_Printhead]

Bell & Howell via Grimco had a guy come out to do the smk3 a few years ago, their tech didn't remove the heater/curing unit to full clean it and I had this problem after. Find a real tech who know printers who will pull it off to clean it properly.