Bowing/ Smiling In Print l25500

[BIG EASY DOES IT]

We have a HP L25500 Printer. We have had it for about a year. About a month ago we started having issues with it bowing the print. We downloaded the new software which contains a menu for "Substrate Straightness Optimization". Now our issue is with consistency. Today for example... I loaded a 54" roll of 3M IJ35C-10. I printed a 50" ruler With lines above and below it. The line had a bow in it (even though last week we had it correct). Anyways, I adjust for the bow and print another ruler. This time the ruler comes out perfectly correct. YAYYYYYY... But NO. Then I proceed to print some small ribbons for Print and Cut. The quality of the print is good but there is a bow in the print. This time the bow is the opposite direction.. Same Media I never unloaded it. Same Profile settings. What the hell is going on. I know one guy on here operates 4 of these same machines. Do you have any of the same issues. HP says lower the curing temp. and raise the number of passes. Which we have tried a little bit. It doesn't work. Then HP tells me it's the material... I have been using the same material for 8 months with no problem and now Your telling me it's the material PLEASE HELP. Guess I should pour this> over it and light the whole thing on fire.

 

[Gino]

Not knowing much about that printer... it sounds like an encoder strip or eye problem. It might help for starters.

 

[BIG EASY DOES IT]

Heres my question though if it was the eye or the encoder strip. I should have irregularities in the print correct? Like blurry lines, overlapping areas, something like that. My printed images look perfect there is just a bow.

 

[Sign-Man Signs]

I'm looking at one of these right now. Is the bow like a hump in the final print and this is a latex printer? Can you post a picture?

 

[BIG EASY DOES IT]

I could take a picture and post it but looking at the picture you won't be able to notice anything. say the left side and the right side are at zero. In the middle is at -2. any image you print has this slight bow in it but when you go to cut it. Since the left and right sides are at zero the plotter assumes that the image was printed correctly and doesn't adjust in the center to the bow. I've tried adding additional segmented registration marks but it still comes out the same.

 

[Nishan]

We also have the same issue. It is a problem with the l25500, an much less of an issue with the lx820. There are too many variables involved when using that much of heat on vinyls. We do print and cut, but not for tight registrations. I do not think it has anything to do with encoder strip etc. You need to check the heating elements, and also the reason you get a smily face is that the head spends longer time on the ends and less in the centre of the print, hence the heat is more in the centre. Try rotating the print, might waste media but cud get the job out.

 

[BIG EASY DOES IT]

What do mean by rotating the print. Say i have to cut 100 stickers and the print to the registration marks is 50X50. It's not going to help to rotate the print because it will still be in the same spots. What are your heating and curing temps with number of passes that you would use for a white self-adhesive vinyl. I'm using HP Profiles.

 

[HulkSmash]

i havn't had this problem. Can you post a pic. It will help..

 

[jayhawksigns]

I had this issue when we were doing some test prints on the 30" HP vinyl that came with the printer when it was set up. The temps were lowered from what the rip settings were in Flexi, and I was feeding the material back so that there was at most 1" out in front of the rollers. Tried different calibration settings and nothing really changed how it printed.

While the tech was here, I switched to our 54" media, ran at the default temps in Flexi for that media, but had the media fed out far enough in front of the rollers that I couldn't see it in the window. Making those changes fixed the problem for us so far.

Knock on wood it hasn't happened again. Was it the media, width of the media, amount of pre-feed? I don't know.

 

[BIG EASY DOES IT]

I don't understand how your going to be able to see a 2mm bow in the print but here is an attached picture. This is also handicap signs that are currently printing. The stuff I printed out earlier has already gone out to the customer.

 

[BIG EASY DOES IT]

I had this issue when we were doing some test prints on the 30" HP vinyl that came with the printer when it was set up. The temps were lowered from what the rip settings were in Flexi, and I was feeding the material back so that there was at most 1" out in front of the rollers. Tried different calibration settings and nothing really changed how it printed.

While the tech was here, I switched to our 54" media, ran at the default temps in Flexi for that media, but had the media fed out far enough in front of the rollers that I couldn't see it in the window. Making those changes fixed the problem for us so far.

Knock on wood it hasn't happened again. Was it the media, width of the media, amount of pre-feed? I don't know.

Unfortunately this scares me even more....making it seem like there is no one variable that is messing this up. We have tried lowering curing temp and upping the number of passes but that doesn't work. I use the profiles provided by HP and they don't work. This is all very unnerving. Because I can get this to print perfect straight lines. I then rip and print a row of stickers on the same loaded material, same temps, same everything and suddenly I have a bow again and this time it's in the opposite direction.

 

[HulkSmash]

Unfortunately this scares me even more....making it seem like there is no one variable that is messing this up. We have tried lowering curing temp and upping the number of passes but that doesn't work. I use the profiles provided by HP and they don't work. This is all very unnerving. Because I can get this to print perfect straight lines. I then rip and print a row of stickers on the same loaded material, same temps, same everything and suddenly I have a bow again and this time it's in the opposite direction.

interesting... what RIP are you using?

 

[ProColorGraphics]

I have been using Caldera VisualRIP+ and been having very similar problems.

 

[BIG EASY DOES IT]

We are using Flexi and using the Flexi Production Manager.

 

[BIG EASY DOES IT]

We also use Flexi and Illustrator to design things. When we print and cut all finished artwork is imported into illustrator on a mac where we use cutting master to create the registration marks and cut lines then is imported back to flexi on the PC production manager for printing. Then is taken off the printer and taken to the Plotter and we run the plotter through cutting master on illustrator on the mac.

 

[richsweeney]

I just ran 50 prints of a 54 x 30 ish sheet with 48 .5 x 1 boxes that had to be cut out. All ran very smooth after I changed to a stable subtrate, like 3m. It was like night and day. The cutter is the graftec

My only question is how to I print 50 copies and still get 50 sets of cut countour reg marks? I had to print each one out individully, a real pain. I am using onyx as a rip.

 

[ucmj22]

Using no experience and going on reason only, If the print looks fine, but has a bow, I would rule out hardware because the head isnt moving 2mm in the middle of its pass. I would have to say, it is a heating issue. If the heat is not even across the print, it will cause the media to expand more in, say, the center of the print than at the edges, and as it cools, it will create the bow. This could also attribute for why you had to adjust the heat twice. when you ran the test print, while the heating elements might have been up to temp, the media itself might not have been. by the time you re-calibrated and started the second print, the media would be up to temp, and therefore would change the results. Like I said, I have 2ero experience with this printing system,so I could be wrong, just using the old noggin

 

[ProColorGraphics]

Using no experience and going on reason only, If the print looks fine, but has a bow, I would rule out hardware because the head isnt moving 2mm in the middle of its pass. I would have to say, it is a heating issue. If the heat is not even across the print, it will cause the media to expand more in, say, the center of the print than at the edges, and as it cools, it will create the bow. This could also attribute for why you had to adjust the heat twice. when you ran the test print, while the heating elements might have been up to temp, the media itself might not have been. by the time you re-calibrated and started the second print, the media would be up to temp, and therefore would change the results. Like I said, I have 2ero experience with this printing system,so I could be wrong, just using the old noggin

This totally makes sense as the bowing issue is less of a problem when I turn the heat down.

 

[Suz]

Matt, I have been watching your posts with great concern, as I my new Latex Printer is about to be set up in our shop and I am hoping I made a good decision!!! As ucmj22's post mentions heat being the potential problem, I have to say I was wondering the same thing. When I have a question about heat being even across my flash cure unit, conveyor dryer, heat presses, or anything else in my shop, I check temperature in different areas with a very handy tool: Raytek minitemp thermometer - has a laser on it and gives you a readout. This little tool you will find advertised for about $80.00 or so, but I think I got mine (new) on Ebay a few years back for 1/2 that price. It is worth it's weight in gold. Good luck!

 

[robracer]

Getting the same results using Flexi & Colorgate rips, & on various stock so I doubt stock or heat is the issue, nor is it the rips.....looking for answers