SP540V alignment / stair stepping problem? photos attached

[NCR]

My first post. Thanks for this great forum.

We're having an issue with a Roland SP-540V printer. Every 3 banners or so (generally 3' x 8' with minimal graphics), I get this alignment / stair stepping problem (I'm not really sure what to "call" it). We've already replaced the encoding strip and that didn't fix it.

Help! Thx

 

[J Hill Designs]

try cleaning the encoder sensor?

 

[Fatboy]

try cleaning the encoder sensor?

 

[ova]

I think it's your print/cut length settings. Not for sure, but I think you have to enter a length that will be longer than your print or you'll get this.

Even though your default is set to xx", if the print is longer, the printer will not just stop, it will readjust and keep printing the remainder of the image.

I know I repeated myself, but don't know any other way to explain it.

Dave

 

[Fatboy]

I think it's your print/cut length settings. Not for sure, but I think you have to enter a length that will be longer than your print or you'll get this.

Even though your default is set to xx", if the print is longer, the printer will not just stop, it will readjust and keep printing the remainder of the image.

I know I repeated myself, but don't know any other way to explain it.

Dave

hey??

 

[NCR]

try cleaning the encoder sensor?

Assuming you're referring to the red light, yes. Once just blowing it out, and later taking it apart and cleaning. Unfortunately that didn't fix it.

 

[J Hill Designs]

network hiccup perhaps? make sure a) not wireless b) no antivirus, c) HD doesnt turn off (power settings in comp)

thats all i got

 

[NCR]

I think it's your print/cut length settings. Not for sure, but I think you have to enter a length that will be longer than your print or you'll get this.

Even though your default is set to xx", if the print is longer, the printer will not just stop, it will readjust and keep printing the remainder of the image.

I know I repeated myself, but don't know any other way to explain it.

Dave

We're printing on roll vinyl, so the length changes from banner to banner. In the VersaWorks program the length setting is greyed out. We haven't made any changes to these settings for the just about 5 years or so we've had it, and that setting has never been a problem.

 

[NCR]

I took a few more photos in landscape mode (rotated from the first set of photos) to hopefully better show how it's "stepping" once the problem begins.

One more thing. It seems to be kind of heat / use related? When the printer starts from cold, it almost always takes until the third banner before it occurs. BTW - I don't think there is magic in the third banner - could be any job.

 

[artbot]

i doubt it could be your encoder strip because an inclusion or scratch would cause the reader to skip a count thus always resulting in a y "0" that drifts further and further to the right. a dirty encoder sensor would result in the same. your print is drifting left. this is more likely an electronically failing encoder sensor.

 

[P Wagner]

i doubt it could be your encoder strip because an inclusion or scratch would cause the reader to skip a count thus always resulting in a y "0" that drifts further and further to the right. a dirty encoder sensor would result in the same. your print is drifting left. this is more likely an electronically failing encoder sensor.

+ 1

 

[jfiscus]

It reads from both left to right & right to left; based upon the travel of the head IIRC - so stair-stepping to either side IS possible. After you clean that strip, double-clean it & the eye sensor. Make sure you clean the strip behind where the eye "parks". If you still have stair-stepping; flip the encoder strip over & try it that way. (it only reads the top half of the strip)

After you cleaned the strip; you did run the test/check/calibration of the strip in service mode, correct? Running the linear calibration test (??? I'm not sure if that's what it's called anymore; been 2 years since I had my Roland machine) should count all of those itty bitty lines going both ways and ZERO OUT if the strip/eye is clean and good. If it fails that test, all you can do is clean again and test again until it passes the test. If you cannot get it to clean & pass the test, then order the replacement strip & eye.

 

[NCR]

Do either the encoder or calibration issues jive with our "from a cold start, it typically seems to happen once we're into the 3rd banner" comment?

Do the components involved get hot or whatever? In other words, why would it not happen when it's cold, but once it's been going for a little while the problem occurs?

 

[InkjetAuction]

Is the linear encoder sensor "riding" on one side of the scale, as opposed to straddling it?

You can adjust the position... there's a single set screw.

~E

 

[Northern Design]

Wow =That's a lot of guessing, clean the encore strip with alcohol first then move to another step. This is a maintenance issue

 

[artbot]

it goes without saying to never diagnose almost any printer issue in bidirectional mode. especially an encoder strip issue.

here are some custom test files for diagnosing stepping issues. one is grayscale (single pixel vertical lines) and the other is single pixel cmyk vertical lines. you'll need to open them in photo shop, canvas size out to 10,000 pixels and cut/past them end to end until the file is the width of your printer.

set your rip to uni- and print this file at a relatively low res' to exaggerate the step y vs the feed going x. in your rip you can trim the file so that you only print the first inch all they way to the width of your platen.

the stepping will show up on a certain point of the file and that is where you just may find damage or dirt/ink splatter on your strip. if the file staggers regardless of how short or long the file is output, your strip is not the issue and most likely is your encoder.

if in uni- and you are stepping to the left, then most certainly you have an electronic issue with the sensor.

also if dirt seems suspect. as you clean and locate the inclusions, the file will improve until is prints perfect. you can keep this file around to run it every week or two to make sure you aren't losing the slightest step over time.

 

[NCR]

Just a quick update. We're in the process of testing some potential fixes. Will post as we know more.

 

[BlueDuck]

Hi NCR & others
I am having an almost identical problem with my SP300.
The printing is drifting. It is not consistant, sometimes to the left then straight for awhile and then in bigger steps to perhaps the right for awhile.
Even the test print will be out between the two passes (which are one directional.)
Turning the machine off & unplugging the power cord sometimes seems to reset it for awhile
I did one job (600mm x600mm) last week that initially looked perfect but when I put it on the sheetmetal it was out of square by 5mm. It had drifted a little all the way(I got away with it - just.)
The problem seems to be too bad to get any good prints out now.
I did have the same issue about 6 months ago. I had a tech out (several times) who replaced the encoder strip & fiddled with alignments etc. I do not think he "fixed" as it continued sporadically after he left but it did settle down (I got a bit used to the odd print drift failure) until just this last week when it is now near impossible to get out a larger print.

 

[BlueDuck]

I might add a bit more to my story- that I have cleaned the encoder strip and then tonight taken it out to cleaned it more carefully, inspected it with my eye glass it all looks as new (I know what a worn one looks like) & finally flipped it over in any case to a new side. result = no improvement!!

I am wondering about the "red eye" encoder reader. I have had a go at cleaning it and if it was a hair or fluff I would have got it but not much else I can do there. Do these readers fail?

Just now I printed the bi directional test print & it was just mush with every pass was in a different place this time drifting left away from the control panel end.

 

[phototec]

My first post. Thanks for this great forum.

We're having an issue with a Roland SP-540V printer. Every 3 banners or so (generally 3' x 8' with minimal graphics), I get this alignment / stair stepping problem (I'm not really sure what to "call" it). We've already replaced the encoding strip and that didn't fix it.

Help! Thx

I just wonder how many people actually READ all the OP's info before suggesting fixes?

He said:

The "stepping" ONLY occurs on the third banner after the printer has run for a while, so if it was a dirty encoder strip or eye, wouldn't it happen on every banner?

Also the OP says he has installed a NEW encoder strip, and still has the exact same problems with stepping on the third banner.

So, how can the stepping be caused by the encoder strip? To me, the problem has more to do with something electrical after heating up for a while.

OP says, it prints fine at COLD start-up, and only after running a while (the third banner) does the stepping problem occur, so wouldn't this be some electrical component that after heating up is failing, and NOT necessarily the encoder strip?