Problem with banding on AGFA Anapurna M4f

[Tim Kingston]

Hi,
I need some help with this problem. I get banding fairly often and don't know the cause. The banding it not banding due to improper feed adjustment; I wouldn't think. When this problem is not occurring the prints look perfect.

If I print on a normal shutter setting the banding looks like strips ( usually a few passes) that were printed with the shutter set to reverse ( gloss like appearance). I've tried to adjust the vacuum for table, belt tension/ alignment is good, bled the sub ink tanks for air and clean / purge the heads quite often. Also, the lamps were due for a change and changed them out. The problem still persists. When I purge the heads I do get less of a flow through yellow and black heads ( ends of the manifold ) than the other two. I also run cleaning solution through the heads and manifold with no problems. Any helpful suggestions would be much appreciated. Thanks.

 

[HIGHSPEEDGRAPHIX]

I ran a Agfa Flatbed a couple years ago at a shop I was at. We had a similar issue with Banding in the black......they ended up changing the head on it. If its a glossy band and matte band then I would think its in the lamps.

 

[Tim Kingston]

I ran a Agfa Flatbed a couple years ago at a shop I was at. We had a similar issue with Banding in the black......they ended up changing the head on it. If its a glossy band and matte band then I would think its in the lamps.

We thought that too but I installed new lamps yesterday, still getting some banding today. Thanks.

 

[HIGHSPEEDGRAPHIX]

maybe clean the lenses of the lamps?

 

[HIGHSPEEDGRAPHIX]

low flow on black and yellow, maybe a clogged line? do you keep soulution in the system on the weekend and when its not being used for a few days?

 

[sheitmar]

Tim,

We're having the exact same issues on our M4F. Were you able to diagnose what was wrong? We typically print in 4 pass bidirectional, but found the banding lines almost disappear in 8 pass bidirectional. It works, but it's not really a solution - our prints now take twice as long.

 

[artbot]

are you sure that your shutters are opening and closing equally on both sides? if not you can get curebanding from one direction being less cured and also wetting a bit more before kicking to a cure.

 

[klmiller611]

Any Solution?

Tim

Did you ever come up with any idea of what might be causing the banding. My Mv is having more and more problems of late with it. I've adjusted the feed, adjusted the heads, replaced both bulbs.

I've also had occasional places where the ink just simply is not curing. I print a lot of signs, 7x44, running 6 at a time, loading 3, then loading three as the print progresses. On occasion, not every batch, not a specific sign out of the six, but one will simply not be cured coming off the printer, totally wet and unusable. These signs are name signs with just black print, no background, not other print. These are name signs for booths at trade shows, I know you've all seen them.

I had been running these in a 2 pass mode, on the dull side of the board, but the ink seemed to get so thin in places, it was a weak gray, again, no specific, repeatable action.

Yesterday, my left lamp did not seem to be cooling like it should, like the fan had stopped, but appeared to be running. The case was obviously hotter than the right after about 20 minutes of printing, so hot that I was concerned of burning myself if I contacted it. I don't know if this has anything to do with it.

Obviously any ideas will be appreciated. Going to go clean some more, and hope for the best.

Ken

 

[Gino]

This is gonna sound kooky, but try putting a cardboard cover over the top of your fan area where the air gets sucked into the fan enclosure on both of them. It sounds like your lamps are being told they are drying too lightly and not producing enough heat, so to speak. It's a mechanical failure and one thing will counteract another until you have banding and non-drying in spots. This will reduce the amount of light regardless if it's new lamps or not and you won't get pure curing/drying. Too much cold air passing through there wil do this. I might've explained it wrong, but it did the trick for us. This is a problem if the area air is too cold.... and virtually in any machine from any manufacturer. This comes from the lamp manufacturer themselves. This bad winter, we had this problem and that cured it. The lamps will test perfectly on their work taable, but not work properly in your machine. The different scenarios you all mentioned was the root for it.

 

[klmiller611]

Thank you Gino

That is truly an interesting thought. I believe that this may be on the right track. A new issue has developed in the last two days which sort of goes along with this. The lamp housings on the Mv (and I think the other M series) are designed (I assume) with an air intake side and and exhaust side. Normally, you can hold your hand up over the housing and feel the exhaust. In the past two days, the exhaust has stopped on the left side lamp, and now the housing gets so hot in 20 minutes, you cannot touch it. After about that time, I assume, some protection device kicks in and shuts off the light. The intake fan appears to be running correctly (from visual inspection) but I cannot see anything on the exhaust side.

Now, with that, the last things I ran yesterday, cured perfectly, of course, I only have 20-25 minutes of run time to do anything, which is not good, but it seems to me that what you describe seems like a viable issue. Now, I have to figure out what is failing here and get it fixed.

My biggest problem is that the machine is 5 years old, no longer in service contract and the nearest AGFA service man is at least 4 hours away. I'd like to narrow down the issues, so if I have to bring someone in, at least it won't eat us alive to fix stuff in a day.

Best
Ken

 

[Gino]

Thank you Gino

That is truly an interesting thought. I believe that this may be on the right track. A new issue has developed in the last two days which sort of goes along with this. The lamp housings on the Mv (and I think the other M series) are designed (I assume) with an air intake side and and exhaust side. Normally, you can hold your hand up over the housing and feel the exhaust. In the past two days, the exhaust has stopped on the left side lamp, and now the housing gets so hot in 20 minutes, you cannot touch it. After about that time, I assume, some protection device kicks in and shuts off the light. The intake fan appears to be running correctly (from visual inspection) but I cannot see anything on the exhaust side.

Now, with that, the last things I ran yesterday, cured perfectly, of course, I only have 20-25 minutes of run time to do anything, which is not good, but it seems to me that what you describe seems like a viable issue. Now, I have to figure out what is failing here and get it fixed.

My biggest problem is that the machine is 5 years old, no longer in service contract and the nearest AGFA service man is at least 4 hours away. I'd like to narrow down the issues, so if I have to bring someone in, at least it won't eat us alive to fix stuff in a day.

Best
Ken

Don't count on it being a cheap fix. The agfa techs don't even know about this lamps/heating/cooling defect even exists. They charge $275 an hour for travel [both ways] time and $250 an hour on site. That will add up very quickly for some dolt to just look at it and scratch his head, saying.... you think the lamps are wha.... ?? Find a local geek and show him the problem. He'll fix it for a whole lot less. You can order your parts from wherever, but don't get their techies in there.

 

[klmiller611]

It would certainly be no cheap fix if I called in the tech. Before taking the lamp apart this morning, I got my flashlight and blew some air down into the exhaust, on the right, it turned readily, the left, not at all, took it apart, and the fan can barely be turned by hand. Fortunately, I had one of those on the shelf, the same side had failed just about 2 years ago. Like a lot of other stuff, these were made overseas, in this case Switzerland. So, I found their website and emailed them. Did not hear back in a day, so ordered one from the manufacture at about $800 for one. Then got an email from the company with a US distributor, those were $175 each, ordered two to have a spare. Today's price is now $250, but another is on the way.

Hopefully this will solve some issues. Going in to install the spare fan now.

Thanks again
Ken

 

[klmiller611]

Follow up on fan change out

Thanks again Gino for the most helpful suggestion. I now believe that the lamp exhaust fan was causing the majority of the problem. I'd never have guessed it without your suggestion.

I changed out the exhaust fan yesterday afternoon, and what had been printing as a banded mess now appears to be OK. Now, I've not printed anything other than the name signs today, but they had driven me crazy over the last month or so. I really believe that the fan was giving me intermittent service and the light was cooling or heating too much.

Never, never would have guessed it!

Best
Ken

 

[Gino]

I just like happy endings.

psst..... don't let Fred or any of the other naysayers know I helped you.
​

 

[Kevin Richard]

The issue with the banding was due to the blue head missing a nossel at the very top. We were unable to see it in the test prints as it didn't look very different than the other test prints. We had the AGFA tech here and he noticed it right away. A very expensive fix, just an FYI on this issue that Tim posted about. This is the machine that Tim was working on.