[leedjc]

Hi all, I’ve got a 1430 which I bought second hand. It was already converted to DTG.

The only problem with it is that the white prints “dirty” until it’s purged, which is usually part way through the print.

I read that the CISS tanks being too high or low could cause it, but I’ve adjusted the height and it’s not made it any better.

I’ve tried different ink and purged it all through. It’s slightly better if printing immediately after a head clean, but is still a problem.

Has anyone got any ideas as to what the problem might be?

Thanks

 

[leedjc]

Here’s an example print....

 

[zerg71]

Hi,

is your printhead 100% healthy? I mean if all the nozzles are firing during the nozzle check? Remember that your printer has only two channels for white and it's in my opinion not enough to print solid white in one pass (probably i will print white two times). If some nozzles are clogged, then it's far from enough to lay down needed amount of ink in one pass.

Secondly, the important thing to consider is that white ink is made of TiO2 which tends to settle from the ink. That means you need to agitate your ink daily, before turning the printer on. Even when doing that, some ink is resting and settling in the tubes/dampers at night or weekend when you are not printing. That's why you need to do head cleans and let "fresh" ink flow to the damper/printhead.

Dampers are also a consumable parts. When they worn off (they're a bit clogged) they blocks the ink flow to the printhead.

And the last thing that comes to my mind is preatreating. The area you want to print white needs to be properly coated with PT liquid. Properly means not to less, not to much and uniformly on the whole area. But I bet you already know that.

As you can see DTG printing is not that easy, especially when it comesto printing white.

 

[GunnyJeeves]

One thing not mentioned yet is waste ink tank pressure...

My waste tank had the hose under the ink level and the temperature went up a degree or two... well, the ink and or the air in the tank expanded and pushed the ink up into the tray. (So each time it hovered over the tray it did get contaminated.)

Check that. My ink hose stays above the ink level now, and no more problems.