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Question bad encoder strip cause banding? head replacement cause heater issues?

signgirl71

New Member
Of course after replacing a head, replacing a fuse, I get all the colors back up and running, do the best I can to align everything - test prints look good. Go to print and there is fuzzy overspray. Knowing I had a little bit of a problem with reading the registration marks I have ordered a new encoder strip as this one has already been flipped. But I also noticed banding in my print, banding like I'm using the wrong profile. I've been using the same legacy profile I have had for years but went ahead and re-installed it anyways. Will the encoder strip cause this or do I now have a profile that has gone bad? I also have another problem where when my machine is in it's sleep mode I can feel that the front of the machine is still warm which makes me think I might have hit a heater switch or something after installing the new head and took it out of its sleep mode to turn the heaters off? Even as I sit here I can hear the click once in a while that I have heard before when it is warming up. Once in a while now it will make a one beep but by the time I get to the machine there are no error codes or anything to read so now I have been turning the machine off because I'm worried something else will go that I can't afford. Any ideas?
Thanks in advance,
Chris
 

damonCA21

New Member
Have you done the test prints in service mode to check the small nozzles as well? This should let you know if the head is working properly.
Not sure about the heater, but you can turn the heaters off in the heater config on the printer and see if that stops them coming on at all
 

signgirl71

New Member
OK, the heater issue is solved but the overspray is still there and I am still wondering if it's a profile gone corrupt or something else. I just changed the encoder strip and it's still doing the overspray with some banding. Finally took some pics - any suggestions would be appreciated. As for the lines not exactly lining up - that's about the best I could get it as that friggen screw or hex I believe is stripped but it is still better then before I changed the head.
 

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Jim Hancock

Old School Technician
Print the fill test pattern in service mode. Watch while it prints and see if you have any obvious banding during the print passes. When it's finished, examine the both edges of each color, take pics and post them please.
 

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signgirl71

New Member
just went back under the hood - lol - noticed the spring that holds the encoder strip on if off. When I go to put it back on it seems loose and won't let me do the encoder set up again. Runs to the end and says turn motor off. I have a feeling this is my culprit but how do I tighten that up?
 

signgirl71

New Member
Thanks Jim - I had that already and already had installed it and everything. When I went back in I saw the spring had come off and it seems pretty loose to me so I reattached it (hoping it doesn't come off again) and tried to do a limitization or whatever you call it again and it kept giving me a motor error. I played with it a while and made sure there were no obstructions or bad wires and such and got it to finally do it. Tried to print again and it's still overspraying. Here's the fill I did before seeing the spring came off. Banding is more noticable in the magenta. This is a problem I have never had before so I'm a bit stumped - wrong time too as finally I'm getting a bunch of work in. Maybe something to do with the caps or head height - I'm just guessing at this point. Guess I will be scanning the internet later trying to figure it out. ugh.
 

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damonCA21

New Member
Did you change the encoder sensor as well as the strip? I dont think thats the problem but is work doing as well. Have you tried printing other colour jobs to see if there is any other overspray as it seems to be only the magenta, which would point to the encoder all being ok.

I would be looking at the magenta head cable as that could be faulty. Was the magenta head the one you replaced or the old one? The other things to look at would be the transistors for the magenta on the main board. If these are failing they can cause random printing. other option could be a bad main board or servo board, but you need to go through and check things bit by bit to narrow it down.
It looks to me more like a signal problem to the head as what you are getting isnt really overspray and the magenta shouldnt be banding like it is
 

damonCA21

New Member
To expand, overspray normally gives a fuzzy edge around things fairly consistently and can often be from a worn print head with deflecting nozzles. What you have looks more like the head isn't turning on and off properly when printing, so some nozzles are continuing to fire when they should be off.
Did you also replace the wipers when you did the head? it is worth double checking they are clean and also that there is nothing physical on the face of the magenta head, but I think in this case it is more signal to the head related
 

signgirl71

New Member
OK, persistence counts. I went through everything and cleaned everything the best I could, made sure that spring was still connected (which I am still worried about it since it seems loose) but I am back up and running! No overspray - hope it lasts!
 

damonCA21

New Member
The strip should be fine as long as the sensor doesn't hit it at all when it passes. The spring is only there to keep the strip taut. If it is loose you can detach the strip from the clamp on the right hand side, make a new hole a bit to the left of the old one and use that to hold it in the clamp which will put more tension on the spring at the other end.
 

unmateria

New Member
Hi :) you need to do printhead alignment (first of all, align the hardware), pf motor alignment (specially if you have horizontal banding with white or too saturated horizontal bands) and bidirectional alignment and then make new profiles. Look for the sp300 service manual since its all there. You can avoid temporaly avoid those (most of then) problems just printing on unidirectional mode and turning off heaters. Leave the media on the same room 24h before printing too if your roll store location has different temperatures than the printing room.
 

DL Signs

Never go against the family
Sometimes the simple stuff gets overlooked. Had a spray issue like that on a SC-540 I used to run after changing a head.
Is that Magenta head seated correctly, if it's cocked at all, not parallel to the bed, or higher than the other heads, they'll spray like that.
 
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