Vertical “banding” FB700

[Glavin_ID]

Hey All,

I am at my wits end here so finally going to post and see if anyone has input. We are getting strange vertical lines in our prints with FB700. I have tried everything possible to remedy. Cleaned carriage rail, cleaned encoder, printed prime bars and jet tests (all look clean). Printing indoor signage on 3mm PVC (which we print all the time).

The strange thing is the solid colors are all printing fine, see text in attached photo. We ran a bunch of old jobs with solid colors and they print fine. It seems to be happening on light colors only. We have run only CMYKW on this machine for over 7 years and never had this happen on light colors before. Any ideas?

 

[balstestrat]

And you are 1000% sure you are now not printing with LMLC by accident?

 

[Glavin_ID]

Yup, 100%.

 

[Glavin_ID]

Figured it out. Flatten transparency worked. No idea why we would have to do that since we haven’t had to do it in the past but it fixed it.

 

[Glavin_ID]

Well, I take that back. Flattened transparency and it worked on a test sheet, went back to the larger sheets and it did it again. I feel like I’m losing my mind here haha. Now to test different versions of the PVC to see if that’s the issue.

 

[Glavin_ID]

Seems to be printing fine on scrap pieces of material we have around the shop so I’m thinking it’s the PVC. Heading to a different supplier right now to try some new full sheets.

 

[Glavin_ID]

Well I know this conversation has pretty much been with myself but we found it was definitely the material. Went out and bought some new sheets from a different supplier and this is the result we got. Hopefully the conversation with myself saves someone down the road from wasting 5 days and a bunch of material trying to figure out this issue.

 

[DL Signs]

I hadn't even see the post... Until now. My first instinct would have been to try a different substrate to eliminate the material as the culprit. There's been quite a bit of that kind of stuff happening lately, it's like all the quality control people quit working.

 

[Glavin_ID]

Haha trust me I’m over here kicking myself for not figuring it out sooner. We have used this material for a while from the same supplier without any trouble, some of the scrap I was testing with was from our last order with them. Now to wait and see what they have to say about it. I can only imagine it will be “sorry don’t know what to tell you, must be something you are doing”.

 

[DL Signs]

I've gotten so much bad material in the last couple years, last one was a batch of Avery lam, 6 rolls from the same lot number, all bad. It's getting crazy.