Mimaki Strange Fading Issue

[Cmiller01]

Hello all,
My Mimaki Jv3 160 has been doing some odd banding. It almost looks to me like ink starvation, but I am not quite sure. We have had this printer for 5 years and it is a great workhorse. We run it all day and most of the time we run it overnight. We havent had any major problems with this machine , although a few months ago we had the encoder strip replaced. It is very sporadic, I could print something for hours and then all of a sudden it freaks out and prints these strange light- normal- light bands in the print. It does this on our normal Avery vinyl material and also on our wallpaper so I know it is not a media issue. Because of the heat we have the room air conditioned....
If I see it printing these strange stripes I will stop it and do a test draw. All the nozzles are accounted for every single time. It seems to like to do it mostly in solid colors, but is not choosy. Also will do it on .tif,.jpg and .eps and on files we have been printing forever.
It sort of looks like what it was doing before when the encoder strip had to be replaced. I have cleaned and dried and encoder strip and the sensors, and cleaned just about everything else I could think of including oiling the carriage bars.I have determined there is nothing left on the encoder strip..... Also all I have checked the wire connections from the computer to the printer and they seem to be plugged in firmly and stable...
I am using Onyx Postershop as my rip and we print on 360x540 12 pass. I tried to go down to 360x540 6 pass and it looks worse on that. I would prefer not to go any slower as this thing is already so slow!!!

 

[WrapperX]

Pictures?

 

[ChicagoGraphics]

Try printing at 720x720 8 pass bi directional

 

[WrapperX]

Try printing at 720x720 8 pass bi directional

I wondered about that - wondered why you weren't printing at; at least; 720x720 for quality reasoning. But it's your shop and you can print at what you want is what I came up with as a reason. So I didn't bother with asking.

However I don't think printing at a different speed will solve what your describing.

Still waiting on a visual aid though to get a better idea.

 

[MikePro]

moar pix! and make sure you observe this site's picture-posting guidlines
or else...

 

[Cmiller01]

I cant upload pictures I have no camera here......we called the tech and he said it sounds like the dampers are going. I happen to think it is the encoder strip, but it was replaced a few months ago so that seems strange. As for the 360x540, it prints pretty nice, and just started here about 7 months ago. We do a ton of repeat work for some chains, and that is how it was set up when I got here with the color filters and all, so that is how they wanted it to stay. The Mimaki doesnt print bad, but it is so slow. I come from a background using Vutek and HP's for the last few years and this thing has been very tempermental compared to those.

 

[serverjohn]

Cmiller...
does it look like what I have attached?
I think I am having the same problem.
*Notice the black swatches

 

[Cmiller01]

Serverjohn,
That looks like you have having a problem with your black printhead. Are you missing nozzles when you do a test draw ? The problem I have is very sporadic, and I have vertical and horizontal lines, and sometimes missing blocks of ink as though it is being starved of ink. I found a small kink in the end of my decoder strip this morning when I went back for a once over cleaning again, I have come to the conclusion that is the root of all my issues.....
Ive also found that if you shut the machine off and switch off the back and leave it sit for about a half hour, things come back normal.

 

[serverjohn]

Whoops didn't mean to hijack. I thought it was similar in that my test pattern is perfect. Just trying to help

 

[gabagoo]

Funny that I read this and not 5 minutes ago I printed a small golf sign and it did the streaking issue. I print at 360 x 720 and ran 4 pass bi directional due to the fact that they are low cost signs. It almost has a look like a form of ink starvation but I know it is not. I might be suspect to it being from possibly to much heat when printing. I ran mine at 45 / 40. If I had run the job at 720 x 720 8 pass I would not be seeing it nearly as bad.

 

[WrapperX]

Typically I never ran as high as 45/40 - we were getting weird vertical streaks as well and it was from too much heat. We brought our heat settings down to 35/30 for most vinyls and 30/27 for most banners.

 

[mkp007]

DX5 Decoder going bad

I too have been having this issue. I think my dx5 decoder board is starting to fail. This happened a while back where about 20-30 inches (in the feed direction) into a print, it would act up majorly with banding and/or ink channel not printing (problem was across the width). I took apart the cables to the decoder and chip and then the problem when away. Now, I'm getting banding 1/2 inch wide at about 2 inches and 16 inches (in X direction) that continue in the feed direction.

This is not due to ink starvation. It could be a kink in the cable but I have been switching them out and have not noticed any change. I'm thinking the capacitor on the decoder is shot. I have ordered another decoder and hope it get it quick. Kind of out-of-luck right now.