Welcome To Signs101.com: Largest Forum for Signmaking Professionals

Signs101.com: Largest Forum for Signmaking Professionals is the LARGEST online community & discussion forum for professional sign-makers and graphic designers.

 


  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Roland RS-640 What is causing this shifting

Discussion in 'Digital Printing' started by Banners Signs Etc., Jun 26, 2019.

  1. Banners Signs Etc.

    Banners Signs Etc. Active Member

    609
    0
    16
    Sep 21, 2011
    Kentucky
    I'm thinking it has to be the encoder strip or reader. Whenever we run let's say an 8 ft banner it starts off centered then by the end there is barely enough for a hem. It also is having a hard time printing crisp lines and shifts sometimes.

    I replaced the encoder strip maybe 5 months ago with a generic and everything was fine for a while, but it seems to get progressively worse. Do encoder readers wear out? Or would it be something different altogether.
    I've cleaned it several times.
     

    Attached Files:

    Tags:
  2. Gino

    Gino Premium Subscriber

    33,968
    2,511
    113
    Jun 7, 2006
    PA
    It definitely looks like 'encoder' something. Strip would be my first thought and unless you have a lotta overspray clogging up your strip, ya might look into replacing the eye.
     
  3. C5 Service&Repair

    C5 Service&Repair Member

    328
    42
    28
    Jan 14, 2018
    Omaha, NE
    Definitely the encoder strip is dirty or needs replaced.
     
  4. Banners Signs Etc.

    Banners Signs Etc. Active Member

    609
    0
    16
    Sep 21, 2011
    Kentucky
    Does the eye generally go bad at some point? Seems near impossible to clean it. We've used this machine daily for 7 years now after buying it used.
     
  5. Gino

    Gino Premium Subscriber

    33,968
    2,511
    113
    Jun 7, 2006
    PA
    Have our machine since 2005. Replaced the eye once, about 6 years ago. Replaced the strip once, but have cleaned it several times and reversed it to make it work.
     
  6. C5 Service&Repair

    C5 Service&Repair Member

    328
    42
    28
    Jan 14, 2018
    Omaha, NE
    Take 2 sponge swabs, not cotton but sponge ones, and dip them into 70% iso Alcohol. DO NOT use 99%, only 70%. Squeeze the excess alky out of them so they are just damp.
    Pinch the strip and slide the length of it. Move the carriage one way or the other so you can get the part of the strip behind it too.
    Allow it to dry about 3-4 minutes and try a print.
     
  7. Andy_warp

    Andy_warp Member

    317
    68
    28
    Jan 28, 2013
    Seattle, WA
    I don’t run a Roland, but that looks like a media feed issue to me. Are you sure the material isn’t walking? Maybe wipe down your pinch rollers and mark the platen with some tape at the media edge...
     
  8. Joe House

    Joe House Active Member

    973
    218
    43
    Feb 5, 2004
    WA
    The encoder sensors rarely go bad in my experience. There should be no physical contact with them and the power supplied to them is generally steady. There's an LED on one side and a light sensor on the other side. If you don't have your encoder strip centered between the two arms, it can rub on the sensor and ruin both the sensor and the strip.
    I have seen them get dirty, which will block the light passing between the two legs. Usually a blast from some canned air will fix that. Don't use a compressor for this as the pressure is probably too high and the air is contaminated unless you've got filters and traps on your air supply.
    The closeup on the letters shows that it's stepping at each pass which is classic encoder problems.

    Blast the sensor with the canned air and clean the encoder strip. I like C5's technique.:) I usually use an alcohol wipe from the pharmacy (or 2 if it's really dirty) but there are usually sharp edges right around there and you have to be careful of cutting yourself. Using swabs would keep the fingers safe.
     
    • Like Like x 1
  9. eahicks

    eahicks Magna Cum Laude - School of Hard Knocks

    2,500
    356
    83
    Apr 17, 2012
    DALLAS, TEXAS
    You can also double up a pair of those white cotton gloves, soak your fingers in alcohol, then clean as mentioned....same process, just easier without having to jam a long foam brush inside the machine.
     
  10. Andy_warp

    Andy_warp Member

    317
    68
    28
    Jan 28, 2013
    Seattle, WA
    I’ve seen the same looking artifact from having to tug fabric to avoid head strikes. We run grand format, and 50-75 foot prints are fairly common. We have to take great care in keeping rollers clean and tensioning the load perfect or we have walking issues.

    Never fun to find out 400 inches in!

    I keep my machine pretty clean so the encoder doesn’t have a chance to get funky. The carriage rails are exposed so I have to clean and lube them daily. Any time an oily rag gets near the encoder strip, it gets wiped clean too!
     
  11. McDonald Signs

    McDonald Signs McDonald Signs & Graphics

    99
    13
    8
    Feb 11, 2013
    Guin, Alabama
    Clean Encoder strip. If banner material is shifting too, use all of the pinch rollers
     
Loading...

Share This Page

 


Loading...