jv3 (wandering margin problem)

[artbot]

need some advice before i start over nighting the wrong parts...

the right margin on my jv3 160sp doesn't stay put anymore. this causes a tons of headaches in that each sheet gets several passes in the printer. so i need the print to register to a perfect consistent margin.

currently, i let the machine measure a thin piece of white tape (to act as "media") inside of the black rubber lane that the media width sensor. that would yield me the same "zero" for the last year. whenever i would pull a sheet to print, it would register at the same spot/margin to the millimeter.

for the last few weeks, i've seen the carriage wander a bit during measuring upon booting. so, i cleaned the sensor, and cleaned the media lane. that seemed to clear up the issue. but maybe not? on closer inspection it seems the "zero" margin even drifts between "measuring" sessions. it's usually off by 1/8" to 1/4".

does anyone know of anything other than a media width sensor that can cause the margin to change between prints? could the motors be losing steps (the printer has developed a tiny "eek" sound upon it changing directions on the right side. haven't located the squeek yet.)?

i'm stumped.

thanks in advance.

aa

 

[Letterbox Mike]

I'm sure you're thought of it but I'm going to throw it out there anyway... encoder strip... every time I hear of anything wandering or walking in the head travel direction that's the first thing that pops into my head. Not sure if it's at play here if this is only happening during media measuring though. Seems like it would also walk while printing.

 

[artbot]

that's not something i thought of (good idea to check). if there's a dirty line that's seen sometimes and not other times, it would definitely cause the printer to lose count during the print without being aware. i think when it returns home (more slowly then when printing), it may be "re-counting" using the encoder strip, thus counting wrong.

what is the standard acceptable cleaner (alcohol, windex?)

 

[artbot]

well, upon inspection the strip has some ink on it behind where the head carriage is parked. a little white one, little magenta one, and a medium sized black one near the top.

i understand that alcohol and water is what is used to clean the strip, but ink isn't going to come of with alcohol. right?

 

[Mentor signs 440]

you might want to use the solvent that is used to clean the machine just dilute it a bit. The "Eek" sound may be the track bar that the print head rides on, it need to be oiled we were told by a tech when ours was doing that. Put some multipurpose oil on a coffee filter and rubbed it on there and it got rid of the noise and worked great

 

[MikePro]

my 70% isopropyl/water mixture and a little patience/effort was always enough to clean ink droplets off my encoder strip, in the past.

After seeing what a couple of spills have done to the plastic covers on my machine, I've always been worried about using printer cleaning solution on the encoder strip. I'm sure it would get the ink off, but wouldn't it burn the encoder strip in the process?

 

[Letterbox Mike]

I was always told to only use distilled water on the encoder strip, that any solvent could haze or fog the surface of it, which in theory would ruin it. If you've got some ink globs on there I doubt water will get it off. Try diluted alcohol sparingly and gently, I'd have to believe they made the strip out of a somewhat chemical resistant material.

 

[gabagoo]

I have always found that my Mimaki (jv3130spII) will start at different areas at the beginning of the print. I dont know if thats what you are reffering to.
For example when I hit "Roll" and the machine tells me I have 52.5" of a 54" roll, is that correct? It has always done that no matter the size. 22.5" on a 24" roll...etc
In Flexi I tell the rip the size on the Mimaki readout and if we are cutting decals afterwards I want at least 1.5" to move in before printing. Sometimes it is at 1.5" or so and other times it seems to go in 3" or more.

I have never had to do panelling since I have owned the printer but that scares me that nothing would line up if the printer head is not sure where the media starts?
I shall check my encoder strip also.


On another note a customer wanted decals printed on silver vinyl. I said no problem, but the printer could not detect the edges of the vinyl due to it being silver. I guess I need to tape a 6" leader to the vinyl to fool the printer?

 

[MikePro]

yup! i fool my printer all the time when i need to print as close to edge-2-edge as possible. I make the automatic 1.5" (or whatever) margin disappear by taping an extension to my media, tell the rip i'm using larger media, and then freely send out the size I need.

 

[MikePro]

in regards to your "eek"ing, my carriage/motor has been making the same noise for the past year or so... usually resulting in a Y-CURRENT error every couple of weeks that I don't lube my rails with 3-in-1. (see lube thread for more useless detail)

i'll keep stewing on the media sensor issue as I have no other ideas, at the moment, other than the media sensor, encoder strip, AND (I don't think anyone's mentioned this yet but) isn't there a secondary sensor that registers the encoder strip? OR even the "zero-point" sensor on the top-right corner above the capping station?

 

[SightLine]

I'd also check that the media sensor itself - on the head carriage has not come loose. Ours has a couple of times in the past - it was still partially held in place but had become tilted. It would still detect the width of the material but not nearly as accuratley until I snapped it completely back down.

 

[MikePro]

OR even the "zero-point" sensor on the top-right corner above the capping station?

scratch that... if the zero-point wasn't working, i would assume a more noticeable issue would occur as the carriage would never seat correctly on the capping station.

 

[artbot]

@ gabagoo for silver or wood veneer, all you need is that white tape inside of that groove where the black rubber is. after measuring the tape the machine is oblivious to the material. but keep in mind, i've hacked the rear sensor that tells if you've raised the feet of the printer so i can basically do what i want and the first boot measurement stays in tact.

one thing you can do on a mimaki (possibly other machines) is enter a negative right margin. my printer stops at -10mm.

i'm off to get some denatured alcohol and a air can. will have to do some plunking around just before i'm forced to overnight an encoder strip. the client will have me shot if i don't deliver their project. it's for a big donor event...

here's the project.

brushed/imaged metal pass, white pass, color pass. all has to be perfectly aligned and trimmed.

 

[WrapperX]

brushed/imaged metal pass, white pass, color pass. all has to be perfectly aligned and trimmed.

Gorgeous work as usual Abot! Hope it works out and everything gets fixed. Wish I could be of more assistance. It's the least I could do after everything you've helped me out with!

 

[MikePro]

Gorgeous work as usual Abot! Hope it works out and everything gets fixed. Wish I could be of more assistance. It's the least I could do after everything you've helped me out with!

+1 ...despite me being completely useless with this particular issue

 

[artbot]

thanks guys... dad is getting a bit tense. the weekend is here. the purple giant is a bit schizo and the 15th of this month is closing.

 

[gabagoo]

you guys talking about cleaning the encoder strip i decided i would clean mine..... now I went and I swear I must have been day dreaming but I cleaned it with a little alcohol and looked at the kim wipe and it was pretty dirty although I think it was also rubbing against the black rubber band that runs along the strip. I did a quick job of it and used very little alcohol.
After tossing the wipe I thought I should move the head out and clean the area there and went back to get more alcohol. I see my cleaning solvent sitting on top of my yellow ink tray cover and then i smell my hand and realize I inadvertantly used cleaning solution on the strip!!!!!!!
egads... I dowsed another wipe with alcolhol and went over the strip again. it looks ok but I have not printed anything today.
Man I have to wake up!!!

 

[signage]

gabagoo are you sure this isn't the problem today

 

[gabagoo]

gabagoo are you sure this isn't the problem today

no !!!! thats later :ROFLMAO:

 

[artbot]

results after cleaning....

well, thanks for all the input. so far this is where i'm at.

cleaned the encoder strip with denatured alcohol. that worked slowly except for the dots of white ink. white ink just didn't come up with alcohol. i used cleaning solution for the white dots, inspecting the strip with a loop and didn't notice any degradation at all.

not endorsing using cleaning solution but as a last resort, wipe it on and have a second dry swab ready to immediately dry it off.

the seems the strip is made of heat stabilized PET with a laser printed microfilm. PET is the most solvent resistant plastic, so i don't know how it's been given the bad wrap as being so delicate. ???

upon boot, the printer measured 61.75" it always measures 61.19" so that is definitely odd. hopefully the purple pain in the ass is done for the next few months. will update if it keeps doing the drifting margin routine. otherwise, thanks for all the help.

aa