• I want to thank all the members that have upgraded your accounts. I truly appreciate your support of the site monetarily. Supporting the site keeps this site up and running as a lot of work daily goes on behind the scenes. Click to Support Signs101 ...

Gandi 3150x2

cwb143

New Member
Something weird happened recently. 24 print heads suddenly quit firing! Cyan, Magenta, and Black. The other 24 are good. I took a filter out and dissected it and it was clean as a whistle. Took a print head out that was bad cut it open and it had ink that was coagulating near the jet tubes as well as the chambers that bolt on top of the heads. so all this ink has been geling up in the print heads. What do you suppose causes this? Im looking at $30,000 replacing heads. I can do that or sell the machine.
 

kanini

New Member
If you have that many out with the same issue I'd contact some company that cleans printheads and ask for a good price on all the clogged heads. If it's gunked up ink there's perhaps a good chance you could get them cleaned for a fraction of the cost it takes to replace them? Just a thought there...
 

cwb143

New Member
Your probably right. I'll look around. At first I thought it was I/O board. but was wrong. First time something like this has happened. We take pretty good care of this printer. We thought maybe it was an ink problem. But I doubt anyone will own up to a bad ink situation.
 

artbot

New Member
i'd try this before getting the heads to a cleaning service. we recently had our used CET installed. unfortunately the printer sat in a crate in the hot texas summer for two months. when we got the printer up and running, we got word that we had clogged heads. the installer removed seven heads, soaked them in CET flush over night. the heads were still clogged. before we dumped $7600 on new heads, i suggested we try cleaning them with NMP. with the heads installed, we syringed NMP into the worst, most horribly clogged head (we did this because we knew it was a gonner and we might be able to send the remaining six to a cleaning service). well that head cleared up immediately and became the cleanest head in the whole carriage. we proceeded to do this to all the heads. now or heads are perfect. we have watched for any adverse effects from the NMP over the months but we've seen none. also, i did test the NMP with the CET uv ink for compatibility. ...no issues.

here's the deal. NMP doesn't melt ink. it's disperses it. head cleaner softens then gums up further up the resin clog. NMP is like a liquid plumber for the ink. it breaks it apart then goes to the next deeper layer.

the normal use for NMP is to clean urethane foam guns, and stripping powder coat. it's also the "green" solvent in HP latex ink. it feels like soap, has no scent (or maybe a light ammonia scent). i get mine from sprayfoamnation.com for $35 a gallon.
 

Typestries

New Member
24 heads in one bank? did you swap any of those heads to a different position? Ink temp issue in reservoirs? Clogged osmosis filter in reservoir/lung that needs backwashing? What ink are you using?
 

cwb143

New Member
Thanks Artbot. I'll give it a try got nothing to lose except 24 print heads LOL. @Typestries It was heads on both sides of the board. So it wasn't electrical. and it wasn't operator error. I've swapped heads before but I don't it was recent enough to make a difference. but the room temp has been ideal. reservoir looks good as usual so i don't know.
 

artbot

New Member
i've never read the msds on the NMP. maybe being a "green" solvent i figured it was no big deal. i get it on my hands, no irritation. just wash it off with soap. i'll read up and be more careful if necessary. that said, if i avoided every material that ever had a spooky msds, i would have never built my business. i've got 25 years of exposure to nasty stuff and i'm the healthiest guy i know.
 

DIGIXTRA

Digixtra
i'd try this before getting the heads to a cleaning service. we recently had our used CET installed. unfortunately the printer sat in a crate in the hot texas summer for two months. when we got the printer up and running, we got word that we had clogged heads. the installer removed seven heads, soaked them in CET flush over night. the heads were still clogged. before we dumped $7600 on new heads, i suggested we try cleaning them with NMP. with the heads installed, we syringed NMP into the worst, most horribly clogged head (we did this because we knew it was a gonner and we might be able to send the remaining six to a cleaning service). well that head cleared up immediately and became the cleanest head in the whole carriage. we proceeded to do this to all the heads. now or heads are perfect. we have watched for any adverse effects from the NMP over the months but we've seen none. also, i did test the NMP with the CET uv ink for compatibility. ...no issues.

here's the deal. NMP doesn't melt ink. it's disperses it. head cleaner softens then gums up further up the resin clog. NMP is like a liquid plumber for the ink. it breaks it apart then goes to the next deeper layer.

the normal use for NMP is to clean urethane foam guns, and stripping powder coat. it's also the "green" solvent in HP latex ink. it feels like soap, has no scent (or maybe a light ammonia scent). i get mine from sprayfoamnation.com for $35 a gallon.

Hi Artbot
Thank you for an useful answer. May I ask what is the full name of NMP?
 

cwb143

New Member
We injected NMP today with a syringe into 24 heads. Each head twice. Then we came back to the first head we did and tried it again. We didn't notice anything special so we decided to let them sit till tomorrow and try again. Keep in mind these are SE 128 spectra heads. They have nano size jets in them so if ink is gelled up in them that NMP needs to soften it up to blow out So maybe letting them sit will work. Unless Artbot has any ideas on our methods. BTW we wore tyvek suits latex gloves liquid proof gloves, goggles, and a breathing apparatus inside a paint booth to work with this chemical (NMP).
 

artbot

New Member
the nano size shouldn't be an issue. i got an old clogged dx4 to clear up once and it has very tiny jets. on the other hand i have three tables covered with every imaginable solvent, resin, and glycol in open containers for mixing my proprietary inks.
 
Top