Printhead Doctor, Just Started Using It

[Smoke_Jaguar]

Finally snagged a PHD for use in the shop on the army of clogged heads lining my shelves. The Oce Arizona 550 GT I got a while back came with a big box of Toshiba CE2 family heads, and I have a good-sized stack of Mimaki 4 channel Ricoh Gen5 heads to knock out. The machine is the bare-bones and apparently discontinued PHD11, but it has nice pressure control, the higher frequency ultrasonic tank and it seems to work well if a bit manual in its nature. The machine was an eBay purchase but came to me in good shape. The tiny capsule filters were the first to go and I swapped to larger 5-micron ink filters (same spec, larger filter and one I have in stock). Other than that, I picked up a Toshiba head adapter for $250 and some cleaning solutions. 4UV and R-UV. The cleaning solutions are definitely going to cost more than the machine in the long run.

Currently working with the Toshiba heads exclusively, so mixed results there. Keeping pressure at around 5PSI (which is the purge pressure on the Arizona and an assumed safe bet) has seemed to be a bit of a sweet spot. R-UV and the 4UV aren't compatible, since the former is solvent based and the latter surfactant based. Not super thrilled with the surfactant approach. Probably better for thinner inks, but seems almost ineffective. R-UV seems to be way more aggressive, but to the point of being a detriment. Plus only a 3 hour safe working time. Cycles are around 30 minutes. I have had good luck using flushes provided by the ink vendor I use as well. Wanting to try other fluids as I go, but that is going to be cost prohibitive.

Heads that seem to recover need to have around 20% or more of their nozzles free to let the fluid move around and do its job. Completely clogged heads are almost a guaranteed loss, as I would've suspected. Soaking the heads is also a good idea, so it's not magic by any means. Running head recovery on the Arizona 550 has been pretty good. The printer sat for 3 years in a building that lacked climate control. 1 white head was a total write-off, but 5/6 heads went from around 40-60% working nozzles to well over 95% just running a single forwards push-through cycle.

As for the machine itself, no gripes on the build quality. It's definitely a niche market machine, so those will be expensive. Documentation is a bit sparse, and I don't expect to see much support for me as a person who bought a used unit. The machine could've gone for a better setup when it comes to draining and swapping fluids, but it's by no means awful.

Seeing as most folks write off heads as they get clogged, I have basically an unending source of heads to play around with.

 

[VizualVoice]

watching this to see your updates. It's interesting.

 

[damonCA21]

It 'may; help with some heads that aren't too badly blocked, and non solvent heads, but I have never seen any proof of it 100% recovering DX4 and DX7 heads. Getting 95% nozzles back isn't that useful for most printers.
The people who were selling them made very bold claims, but if they were recovering so many heads back to perfect working order, how come they were never selling any of these heads, or released any verifiable videos?

I think the reason it became a niche product is because it just didn't work that well

 

[damonCA21]

As an aside to this, anyone can pretty easily make a machine that will do the same thing from an ink pump, power supply and hoses and connectors. Ultrasonic baths are cheap to buy separately.

 

[netsol]

i don't have it with me, but, you should discuss with VLAD who invented the printhead doctor. i will send you what contact info i have when i go to my office
he has been very helpful in spite of the fact that i use a chinese knockoff, not a real printhead doctor
he sells MANY different flush/cleaning solutions. depending on the chemistry of the inks that have clogged the heads
i assume most of your machines are DTF & UV? you recently got a Oce'/ Arizona . they have special flush solutions (and i assume special recommendations for how to clear those heads)

i am jealous, you will be able to adjust temperature of your flush solutions, (i have to use an aquarium heater)

typically, if i am unsure of the chemistry of an ink type, i request the form with all the environmental info for an inkset from the manufacturer (this normally gives you a good idea what the solvent in an ink is.
then i normally "whack" the flush solution i am using with my closest guess at the magic elixir that restores the head to full flow.
you want a solution strong enough to clear clogs, but not strong enough to delaminate that plate below the nozzle plate

 

[Smoke_Jaguar]

To be fair, almost any machine can be built with the ready access to commodity parts and information on the internet. I've been using standard pumps and stuff to clean heads in-situ for a while, but it's nice to have a nice monolithic machine that's well put together to do the job. As for the ultrasound, the 75khz system is far less destructive than the common 40khz stuff used for removing rust from old bolts or whatever general cleaning purposes. Sometimes the cost of the machine isn't the parts, you're buying into what others have both built as well as things they've learned. The older you get, the more projects you're going to have stacking up. Sometimes it's just worth writing the check and focusing on other things. If you have built one you're proud of though, hell yeah, show it off. One of the fun things about forums is seeing the cool stuff people build. There's some seriously talented mofos kicking around in here.

As for 95% recovery, that isn't hard to push further with a second cycle. The main thing is, if there's good flow, you can usually flush more gunk out. Having a machine like this seems more like a maintenance device than it is one of necromancy. I just happen to have a lot of heads that have been sitting in bags since 2020 of the same type to test, so that repeatability is great for me.

When it comes to Epson heads, you're talking some of the most fragile heads in existence. The things can barely handle 2 PSI without delaminating, they are super vulnerable to lots of solvents and the adhesives that bond the nozzle plates on seem to have a limited shelf life. But, that said, nothing wrong with seeing if you can push a head from 'rough' to serviceable if you're already to take the hit of getting a new one.

Even Digiprint seemed to have done an ultrasonic cleaner, and some OEMs have dabbled with them. For printers where getting to the head and being able to hook lines up to the head in-situ is possible, it can be an ideal way to clean a head. Being able to move a cleaning fluid through on circulation while filtering out built up debris and whatnot is a really good idea. Especially when you compare it to just barfing out more ink through the head and hoping whatever it is blocking the nozzles gets forced out.

As for the ultrasonic, it barely runs, the magic is in the solutions, soaking and breaking down clogs with constant movement of a solvent or solution. Relying on just the ultrasonic is a great way to have a head that flows like a lawn sprinkler but just bleeds all over the place and doesn't work. The trick is keeping those nozzles in their original condition, not blasting them out with cavitation by constantly blasting through the head with high energy ultrasound. If you ever get bored and have access to a 100W or more ultrasonic tank, toss an Epson head in there for 5 minutes and watch it get obliterated.

 

[netsol]

It 'may; help with some heads that aren't too badly blocked, and non solvent heads, but I have never seen any proof of it 100% recovering DX4 and DX7 heads. Getting 95% nozzles back isn't that useful for most printers.
The people who were selling them made very bold claims, but if they were recovering so many heads back to perfect working order, how come they were never selling any of these heads, or released any verifiable videos?

I think the reason it became a niche product is because it just didn't work that well

they work very well for routine maintenance.
the problem is, buy the time most people think about using one, it is too late

 

[Smoke_Jaguar]

i don't have it with me, but, you should discuss with VLAD who invented the printhead doctor. i will send you what contact info i have when i go to my office
he has been very helpful in spite of the fact that i use a chinese knockoff, not a real printhead doctor
he sells MANY different flush/cleaning solutions. depending on the chemistry of the inks that have clogged the heads
i assume most of your machines are DTF & UV? you recently got a Oce'/ Arizona . they have special flush solutions (and i assume special recommendations for how to clear those heads)

i am jealous, you will be able to adjust temperature of your flush solutions, (i have to use an aquarium heater)

typically, if i am unsure of the chemistry of an ink type, i request the form with all the environmental info for an inkset from the manufacturer (this normally gives you a good idea what the solvent in an ink is.
then i normally "whack" the flush solution i am using with my closest guess at the magic elixir that restores the head to full flow.
you want a solution strong enough to clear clogs, but not strong enough to delaminate that plate below the nozzle plate

When I turn on my heater, it smokes. Used machine, lol. The heating element is up really high, so I have to dump a lot of cleaner in to cover the element. We are an all-UV shop, since the ink basically stays liquid for years if kept in the dark, it's the best bet for recovery. We do some aqueous as well, like the Epson TFP heads. Messaged Vlad before, but mostly dead air from them and I am actually buying stuff from them. But I think their contact page is broken again. Talked to the guy before, and he's a smart dude.

One of these days I just need to find someone who can do the business side of things. Being broke all the time sucks and I tend to avoid bugging the pros unless I have the budget to buy stuff from them as well.

 

[Smoke_Jaguar]

Yeah, that ain't recoverable... Ricoh Gen5 4-channel head from a UCJV300 with no flow on the cyan channel. Took a drill bit to get down into it.

 

[kehall]

As an aside to this, anyone can pretty easily make a machine that will do the same thing from an ink pump, power supply and hoses and connectors. Ultrasonic baths are cheap to buy separately.

40KHz ultrasonics are a plenty, 75KHz baths are harder to find.

 

[netsol]

Recovery Fluids

Recovery fluids for Print Head Doctor

digitalsigntech.net

this is vlad's website. he invented printhead dr. they are very happy to transfer you OR GIVE OUT HIS CELL PHONE for questions

 

[Smoke_Jaguar]

Yup, been ordering the expensive dranks from them.

 

[netsol]

I know very little about us chemistry.
what hardens the ink in your bad heads?
you would think it isn’t cured by uv. Light INSIDE a printhead
pinholes letting light in from hoses or seams?

 

[Smoke_Jaguar]

Sometimes ink can catalyze and harden without light, sometimes it happens in the lines or in the head itself.

 

[netsol]

Sometimes ink can catalyze and harden without light, sometimes it happens in the lines or in the head itself.

I always assumed when it hardens in the lines, the lines we cheap shit that looked legit. Small pinholes yielding tiny clumps that kill your heads. When you use a drill bit, do the ink shavings dissolve in acetone or MEK?

they must dissolve in SOMETHING (and if it is something that doesn’t destroy the he’d WE WIN!

now get back in there and get started on chemistry class!

 

[Smoke_Jaguar]

They do dissolve in acetone at high strength, haven't tried MEK. That said, getting the gunk purged safely is an effort in futility, so far.

 

[netsol]

1) identify a solvent that dissolves the hardened inks
2) test to see if it destroys the integrity of the printhead IF NOT
3) find a filter element that traps the gunk"

YOU are more than up to the task

 

[Smoke_Jaguar]

When you're trying to dissolve stuff in a blind hole, it can take weeks.

 

[netsol]

looking at some of your early postings refurbishing printers makes me feel like an amateur

 

[netsol]

40KHz ultrasonics are a plenty, 75KHz baths are harder to find.

i am not sure WHICH FREQUENCY gives you less chance of destroying the internals of the printhead

we have used ultrasonics on many different types of equipment but these printheads are fragile like your grandmother's christmas ornaments

I WOULD BE STARTING with a marginal good printhead, varying the temp (remember my aquarium heater, much easier & more predictable) pressure
(the real printhead doctor has bypass valves, i believe) intensity of the ultrasonic cleaning) & chemistry (I HAVE FOUND that vlad is more than willing to discuss
chemistry