Need Help l25500 Printing Blurry on some passes

[Kelcy Deeds]

Anyone have any idea why my L25500 would be printing like this? Its been working fine so far, though it has taken me a while to figure out all the right temperatures for every different vinyl, this was printing on GF203 vinyl at 16 pass with 220 drying temp, 235 curing temp, and 35 for vac. I cant figure it out cause it will print many passes correct and then it will have one really ugly looking pass completely randomly. Thanks for any help

 

[papabud]

ok my guess is its one of 2 things.
watch your material run, is it bunching up in the print zone like the vac is not pulling it down
the other might be a bad cable issue where the head is getting a poor signal

 

[MikePro]

if the material isn't buckling/tunneling during the print, then I would guess it having something to do with media the feed.
I get those misaligned prints on my HP at the end of my roll, when the printer is trying to tug on the last bit of vinyl that is taped to the core.
either that, or your take-up reel could be inconsistently tugging on your waterfall & slightly pulling the vinyl through the printer faster than it is intending to feed the print.

 

[Kelcy Deeds]

Ok, I just did a printhead alignment so ill see if that helps and also i have the take up roll option off because i'm just doing small 2ft strips. Also I forgot to mention that i've heard a loud screeching sound at the end of the print, I don't know if that has to do with anything. never heard it before.

Would too much vacuum also cause this? i've turned up the vacuum to 35. up from the stock 25 because i keep getting jams. To me it looks like the carriage is to low and if the material is slight off the platen or curled just a tad then it hits the media. It makes me think i have a problem with the vacuum but i can clearly see the vacuum pulling the vinyl down, so I'm kinda stumped.

 

[Ian Stewart-Koster]

"end of roll"... I think that is the key... all sorts of gremlins lurk in that last metre!
Start a fresh roll, and see if it happens after the first 2 feet have passed.

 

[Kelcy Deeds]

It's a new roll already

 

[JTBoh]

Looks like you need a thrice reticulated focusing laser. Mine conked out a few years back, had to order one from Valles Marineris. Guy named Marvin.

 

[sts_par]

This is a long shot but.... have you recently run the end of a roll through the printer. Sometimes the adhesive that they use to attach the material to the roll can come off with the media and get transferred onto the printer's media path somewhere. This could randomly grab the media and cause the registration to be off. The screeching sound could be the media dragging across that adhesive at the end of the print cycle. Just a possibility.

 

[Kelcy Deeds]

Ok, I got in contact with a guy who will sell me a thrice reticulated focusing laser for about 8000$ so I went ahead and bought it. Does anyone know how to install this?

 

[Kelcy Deeds]

Hahaha, jk. Anyway I actually haven't gone through any rolls in the last few weeks.

 

[Kelcy Deeds]

I did a print head alignment yesterday and I haven't seen the problem at all after that. I guess maybe with getting quite a few head strikes that that could cause them to go out of alignment. Idk

 

[MIMO]

Anyone have any idea why my L25500 would be printing like this? Its been working fine so far, though it has taken me a while to figure out all the right temperatures for every different vinyl, this was printing on GF203 vinyl at 16 pass with 220 drying temp, 235 curing temp, and 35 for vac. I cant figure it out cause it will print many passes correct and then it will have one really ugly looking pass completely randomly. Thanks for any help View attachment 132137 View attachment 132138 View attachment 132139 View attachment 132138

I've been running L25500s x3 the last 6 years and yeah, they can be tough. To what the guys above have been saying, your media or carriage likely aren't travelling properly. A few things stick out:
-your drying temp can't be 200...it only goes up to 131F
-have you done a carriage rail clean and lube lately? If not do a couple of cleaning and lube cycles...it may be "grabbing" a little as the carriage travels back and forth
-your temps, vac and # of passes are really high for SAV so you may be cooking your SAV. If you're getting jams/head strikes the media is likely buckling from the heat. Reduce your heat and cure temps, reduce your vacuum and reduce the number of passes. 12 pass should be more than more than enough for really crisp resolution on an SAV.
-the heat issue can be compounded by the fact you are doing short runs, so your media is going through a lot of heating and cooling going on which can cause inconsistency. Similarly, if you're cutting your prints close to the end of the previous job, that first part of your next print has been exposed to the heaters and curing modules twice. These machines definitely prefer to do longer runs versus shot.
-I'm not sure of the overall quality of GF205 but when I've tested some bargain basement vinyl it will definitely produce a more pixelated result, but it would do it consistently, not just in certain spots

Do the carriage clean and lube if you haven't recently and lower your temps, vac, and passes. I run Oracal 3651 almost exclusively (which is indeed different than the GF 205) and I run 10 pass, 600dpi, 129F drying, 205F curing, 15 vac, no warm up drying offset, no warming curing offset, min drying power of .6, ink limits of roughly 200 and I always make sure I'm releasing jobs in such a way that the machine doesn't have a chance to cool down between jobs.

 

[MIMO]

Oh and yeah, you want to run a printhead alignment after anytime you've had a head strike / jam for sure.

 

[Kelcy Deeds]

Sorry! meant to say 120F drying temp. I turned it down from the 131 because i would keep getting head strikes right when the print would start and to me it seemed that the drying temp was to high so it would curl the edge of the vinyl just ever so slightly, and enough for the head to hit the vinyl. and when i turn the temp down on drying then it doesnt strike, but maybe i should turn the cure temp down a tad. i had it on 16 pass because when i sent it through with not enough passes then it just came out oily. I will copy all your settings and go from there.

 

[Kelcy Deeds]

I'm sure i will probably have to tweak a bit since I'm running different SAV but its a good starting point i guess.

 

[Kelcy Deeds]

I cleaned the carriage rail this morning and while i was doing the task I noticed that quite a few vacuum holes on the right side of the platen were all clogged up so i cleaned the whole machine a bunch and now everything works great. No more jams and i'm running at 10 pass with .8 drying power at 130F. Before, that same temperature would always cause jams.

Thanks guys for all the help.

 

[Kelcy Deeds]

oh and while cleaning the carriage rail i found a little piece of felt at the end of the carriage rail. thinking it may have been making the sound. also the carriage rail was filthy. I bought the machine used recently for 1750$ and put new print heads and it worked great, or so i thought. lol thinking its working good now though

 

[dypinc]

Did you examine the belt that drives the carriage. That is a known failure point that at some point would probably need replaced.

 

[Christian @ 2CT Media]

You need to get new felts for the carriage... If you are seeing chucks of felt your felts are damaged and you will have wobbles and dragging on the carriage which will eventually damage the carriage rails.

 

[flyplainsdrifta]

+1 for checking the belt. I've had one explode mid print and wreck some heads and whatnot. not cool.