HP R1000 prints scratches very easily....Need Help

[ToTo]

a curious question: if you reduce the vacuum do you have to watch for substrate lifting so it doesnt hit the printhead?

Thats why I said, to reduce as much as possible. If rigid substrate is not bent, you can go quite low with the vacuum

 

[Brandon708]

Well, if it works go ahead, but I wouldn't use a wire brush. Usually a fingernail will suffice. Heck, I wouldn't put a wire brush to anything painted or printed. Sounds like a disaster on purpose.

May I ask, what trimming are you doing that you need to cart a 1/2 printed panel around the shop ?? Reason being..... the more you handle it while somewhat uncured, the more chance of anything happening to it.

Those scratches look like you have little stones or shrapnel on your tables. I also don't understand how WATER can ruin a sign from just getting wet ??

Maybe I'm misunderstanding, but this is direct printing to the substrate, correct ?? You're not printing vinyl and laying it on one side at a time ??

When we have delicate signs needing to be flipped over, we Have thick carpeting we lay down and we still make sure we don't slide it around.

Maybe I was miscommunicating the process for us.
-I start with trimmed blanks that we cut
-Load the printer and print one side
-Take the printed sign and reload for side two
-Take the sign to trim if needed (phonematic shear red thing in the photo that says One Up Signs)
-Round corners
-Add grommets

I am very cautious about these panels not getting scratched and handling them with extreme care. I do blow off the table and shear when I have a printed sign to trim (usually only signs with full bleeds that don't fully bleed) Usually trimming off a 1/16" from the signs.
The grey Better Homes and Gardens sign I notice was scratched when I was putting on the grommets. Not the only time it happened just made me ask for help on fixing it.

As for the signs getting wet situation it happens when a sign panel is wet and they are two that are put together. The water and rubbing together turns the signs into water color painting. Imagine a installer getting a real estate sign panel that is wet and laying it on another sign panel. That is when it happens.
I will try to recreate this with the old sign panels I have and post a photo.

 

[Gino]

Don't know if others do this, but we hand clean our table tops when putting signs on them, especially freshly printed ones. Forced air cannot do it alone. That's why years ago, everything got tacked down 2 or 3 times in different directions.

About the only time we're somewhat careless, is when the masking is still on the blanks.

As for the water problem...... I don't think I've ever heard of water reconstituting already dried inks. How in the world do they hold up against rain or ice or some kid with a water pistol ??

Nice setup

 

[Brandon708]

Don't know if others do this, but we hand clean our table tops when putting signs on them, especially freshly printed ones. Forced air cannot do it alone. That's why years ago, everything got tacked down 2 or 3 times in different directions.

About the only time we're somewhat careless, is when the masking is still on the blanks.

As for the water problem...... I don't think I've ever heard of water reconstituting already dried inks. How in the world do they hold up against rain or ice or some kid with a water pistol ??

Nice setup

you're right about the air not being enough to clean the table properly. I have to do better cleaning the table.

Thanks!

 

[greysquirrel]

Lots of good answers, fought this for a while until creating a profile for the 2nd side with lower temp and slightly less vac. Always thought 2nd side was scratching until we realized that what was really happening was that the ink on the belt was heating and pulling ink off of side A, much happier after creating that second side profile!

second side profile resolves almost all of the issue. less vacuum is key. The vacuum on the printer has zero affect at holding down the ACM. The weight of the material does all of that for you. As far as "better options" Only the Swiss Q has a better IQ than the HP Latex flatbed printer. Every printer has pros/cons, as well as work arounds...too many pros to diminish the value of the R series and its quality over the competitors...HP could sell the front end software alone for job management and make a killing...

 

[ToTo]

a curious question: if you reduce the vacuum do you have to watch for substrate lifting so it doesnt hit the printhead?

Double sided printing is done on rigids, where you have a defined leading edge. These types of substrate are not in need of high vacuum, since they are not bent under normal circumstances. If you are going on cardboard, edgeholders might be always necessary. And the crash sensors will act before printheads might touch substrate.

 

[ToTo]

second side profile resolves almost all of the issue. less vacuum is key. The vacuum on the printer has zero affect at holding down the ACM. The weight of the material does all of that for you. As far as "better options" Only the Swiss Q has a better IQ than the HP Latex flatbed printer. Every printer has pros/cons, as well as work arounds...too many pros to diminish the value of the R series and its quality over the competitors...HP could sell the front end software alone for job management and make a killing...

Not agree, since the pinch rollers can stop movement for a very short time, but this can affect leading edge misalignment

 

[Brandon708]

I've noticed that even ridged materials need as much vacuum as possible. Most are warped even though they look straight, and ridged materials are the ones that I worry about hitting the print heads. Especially when the print zone is warmer and can change the shape of the materials causing them to lift.