Prints are bending to the left! Epson SureColor 30670 and Onyx Rip

[nbk]

I've used many brands of large format printers, several different RIPs, starting in 1996.
I never saw this before. Facing the printer, prints are bending to the left, NOT skewing.
The media is tracking perfectly.

The resulting print (heavy coverage) on the right margin moves 1.5" in 7 feet, but it's totally inconsistent.
The print is not a rectangle, the horizontal leading and trailing edges are straight.
The vertical edges are curved.

Heavy coverage ink seems to curve it more, an 8' banner with a lot of white space, only curved about 3/4" in 8' (bowed in the middle actually).
See attached picture, the text is perfectly horizontal and the edges curve to the left (they are not straight).

Thanks for any help...

 

[Jester1167]

I am assuming all printers are basically the same. On a Roland my first guess would be a bad or dirty encoder strip. If you have one try cleaning it with a soft cloth and soap and water. They can be damaged even worse with harsh cleaners or abrasive cloths.

 

[nbk]

Found Timing Belt on Alibaba

There is a timing belt, listed on Alibaba:
Printer timing belt for Epson SureColor SC-30670 Printer
I'll see if I can find it on the printer & try to clean it.
Thanks,
Neil

 

[jfiscus]

I am also going to go with a dirty encoder strip or encoder reader. Can you run an encoder test or similar on your machine. I used to have a lot of problems with this on a Roland printer and it resulted in similar prints to what you're showing. I have never seen this on our Epson (yet, knock on wood!) but I'm betting that is what it is.

 

[TrustMoore_TN]

I am assuming all printers are basically the same. On a Roland my first guess would be a bad or dirty encoder strip. If you have one try cleaning it with a soft cloth and soap and water. They can be damaged even worse with harsh cleaners or abrasive cloths.

+1

 

[nbk]

Service tech coming tomorrow...

Hi,
Encoder strip appears clean and in good shape. I do agree though, that this should be the problem. It's like it misses reading a few encoder bars when it starts each row, so each row starts further to the left. If it missed bars in the middle of the row, there would be vertical voids in the print.

Tech coming tomorrow for a different repair, he will check out the encoder strip & it's sensor on the head. Over the phone today, he asked me to clean the two media sensors under the head, dirty but no help.

I am currently rasterizing prints in Photoshop then pre-skewing the top of the prints to the right, they come out almost straight (trimmed later on the table). The printer is skewing 1/4" per foot (it's not linear, that's average).

Thanks for the replies,
I'll keep you posted,
Neil

 

[jfiscus]

Hi,
Encoder strip appears clean and in good shape. I do agree though, that this should be the problem. It's like it misses reading a few encoder bars when it starts each row, so each row starts further to the left. If it missed bars in the middle of the row, there would be vertical voids in the print.
Thanks for the replies,
I'll keep you posted,
Neil

That is not true, if it is miss-counting going one direction, it simply "off-centers" the print by that much. It does not only count marks on the strip through the print; but it counts them all the way from the capping station all the way across its travel range every time it moves.

 

[Snydo]

What was the issue nbk? Or did D1 just throw a new print head in it and call it good?

 

[nbk]

Printer fixed

The repair guy came today, a day late.
The printer had two other problems as well:

1. It was running out of magenta at the head during heavy magenta coverage. The "pump & cap" was replaced, that problem fixed. This was not related to the two other problems.

Related problems,
2. Error code 150C that indicates the plastic gears in the head rest area were malfunctioning. These gears lower and raise the head at the rest / cleaning area.

3. Print drifting to the left, creating the curved skew to the left.

FIX: The sensor that reads the timing strip was dirty. The tech brought a new one. It was the wrong part, so he cleaned it.
It turns out that the 150C error occurred because the head didn't know where it was, it was not moving back to the right enough to engage the gears. The dirty sensor was causing the margin to drift to the left during the prints. The gears were left alone.

After he left at 3pm, we printed solidly for the next 3 hours, all perfect.

My comment earlier, about vertical banding (if the timing strip had been bad) was related to the tech directly from Epson support, I didn't have that issue.

Thanks for all your help.
nbk