Why do inkjet heads clog?

[time]

It's important to remember that different manufacturers use quite different techniques for depositing the ink onto the paper. In particular, there is Canon's 'bubble-jet' system where the ink is heated, and Epson's microscopic piezo impellers. Consequently, the ink formulations are radically different. I wonder if the cartridge refillers care?

Anyway, I've been told by someone who ought to know, that Epson heads almost never clog if you stick religiously to genuine Epson inks. And here's something in support of that claim:

http://www.epson.com.au/FourFacts/fourFacts.html

In particular, check out the third fact concerning the required cleans per cartridge.

 

[Fushigi]

I've had problems with refilled cartridges on the Canon & Epsons that I had so I've learned that the best results (except for financial results) are obtained with OEM cartridges. I'm reasonably sure, in fact, that refilled cartridges are at least partly to blame for the demise of my old Canon.

And as much as people knock HP DeskJets, I'm way more satisfied with my 990 than with any other inkjet printer I've ever used.

- Fushigi

 

[Pradeep]

My Epson C80 requires a head clean at least once a week. Using geniune inks. I imagine that as the droplet size reduces, the chances of clogging increase. The C80 has 4 picolitre minimum droplets.

 

[Pradeep]

http://www.epson.com.au/FourFacts/fourFacts.html

In particular, check out the third fact concerning the required cleans per cartridge.

Absolute bullshit if I've ever seen it. I have used the original Epsons that came with my C80, and they clog just as much as the OEM tanks I'm using now. At least they aren't spewing the "non Epson inks will void your warranty UD that they used to spew. They are simply trying to justify their outrageous pricing. I believe the cost of ink from factory carts is worth more than gold, when you work out the cost per gram.

 

[Pradeep]

OEM = non Epson (from carrotink.com)

 

[Tea]

I can't speak for inket refills. I haven't owned an inket, let alone refilled the cartridges, since my wonderful old Deskjet 500. (Err ... that was Tannin's, I mean. I wasn't born yet. Sort of a racial memory, or something.) The DJ500 lasted for more years than I could count without using both hands, and mostly ran on refilled ink. They didn't have those natty little refill kits in those days, I just bought a half-pint bottle of the stuff. But that was back in the days when the words "HP" and "quality" used to sometimes appear in the same sentence, and it didn't also have the words "cruddy", "shoddy" or "appalling" in it either. Which is to say quite a long time ago.

I used to use non-genuine carts in my HP 5Ls and 6Ls though. Refills never gave the same print quality or lasted anywhere near as long as you expected, but the 5L/6L cart is exactly the same as the one that some of the Canon printers use. (Which, seeing as Canon make them in the first place, should be no surprise.) HP 6L cart? AU$160l. 100% identical Canon cart from the same factory? AU$120. You don't have to be Einstein to work that one out.

 

[Prof.Wizard]

All inks clog, according to their quality of course that is more or less. I usually find my inks clogged after long (month or so) of non-operation of my printer. And even that, only some times.

I think EPSON is very good in its inks however. Lexmark AFAIR was fine too.

 

[time]

My Epson C80 requires a head clean at least once a week. Using geniune inks. I imagine that as the droplet size reduces, the chances of clogging increase. The C80 has 4 picolitre minimum droplets.

This is the sort of response I was hoping for.

Firstly, I want to make it clear that I think that all inkjet manufacturers are pirates, and I'll single out Epson for going from not too bad to sometimes bloody awful in their printing costs. The separate ink refills for the C70/80, for example, are a cynical exercise because they're double the cost of the Canon equivalents (although Epson rightly claims extra features for their base ink such as it being fast drying, waterproof and fade resistant).

But I also have known for some time that genuine Epson inks contain solvents etc that minimize the need for regular head cleaning. It is absolutely true that you can often resurrect a clogged head by swapping in a genuine cartridge.

Epson inks are fragile. Last time I looked, the shelf life was only six months. They need to remain sealed at all times to prevent moisture or air contamination.

I believe Epson's test was authentic (i.e. no manual cleaning required with their own cartridge). I think the real question is why people like Pradeep (if he's sure about those carts that came with the printer) can experience regular clogging while others apparently don't.

BTW, unless they changed the specs, the C80 has a minimum droplet size of 3 picolitres, not 4.

 

[Pradeep]

When I say head clogging I mean that when I print the test pattern, some of the lines aren't printed. I do the head clean thing, sometimes twice, and the test print works fine again.

I got the C80 when it was first released, so I would imagine that the inks were relatively fresh. Now if I were to print 50 prints in a row, one after the other, I'm sure I wouldn't have any clogging. It only occurs after a couple of days of non use. What is a real pain is when you waste a good sheet of photo paper because the heads are blocked. I need to change my method of operation to test the heads before printing I think. One thing to note is that I didn't have as many clogs when I used an Epson Stylus 670.

The only terminal head clog I had was with an HP DeskJet 500, the ink leaked out after many months of non operation and it was a write-off.

Yes sorry 3 picolitres

 

[Pradeep]

OK I see the problem. It looks like the Epson tests just print one after the other till the ink runs out. The methodology is not clear. Now this doesn't really correlate with real life use, where one would prob print a few images, have a few days non-use, then some more etc. The clogging only really occurs after periods of non-use.

 

[SteveC]

For the latest Epsons, I think you can still use the generic inks, but you can't refill the Epson cartridges. They have a sensor to tell when the ink level increases, and they won't print. I have the Stylus Photo 780, and I normally use the genuine ink cartridges because I haven't had very good results with the generics. You're correct about the six month life-span, but that has never been a problem for me.
It seems to get clogged after long periods of inactivity, or after printing with thick paper. All I have to do is run the quick nozzle check, then if it needs cleaning, I run the head cleaner. After 1 or 2 tries (and in very rare cases 3 times), it prints the test pattern just fine and I can continue. I've never had an Epson that became permanently clogged, and I've had several over the years.

Steve

 

[timwhit]

Sorry this is a little OT, but how do color laser printers compare to the newest inkjets?

How about thermal printers? They are supposed to be much cheaper to run than inkjets I thought.

 

[Cliptin]

I have an HP 722C that I print from maybe once in two months. I've never had a clog problem. Maybe it matters that I don't keep it powered on when it is not going to be used.

Recently, within the last four months, I put a dust cover on it so that the papers would not have dust ditting on them when I wanted to print. It won't hurt the print heads either I guess.

 

[Tea]

We used to get the following pattern with Epsons:

1: wonderful reliability in the initial period, practically zero percent return rate.

2: significant number of failures on the first cartridge replacement. Always the first one - if they survived that first cartridge change, they would go forever. Quite possibly this was contributed to by people's failure to RTFM, but I don't know for sure.

But that was quite a while ago, five years or more. These days it just doesn't seem to be the issue that it once was. Our failure rate with Epsons now is miniscule. I think we have had two Stylus 460s and a 440 come back. (I don't count the cheap and horrible little 480 - we bought ten of those sight unseen and had roughly 50% come back within the first few weeks. Tannin sold the warranty returns off to the trade below cost and dropped the model from our line-up.)

Mostly we sell the #2 and #3 Epson models: Stylus C40 and 670/C60 till recently, now the C41 and the C61. I don't know how much cleaning and clogging they get, but no-one ever rings us up and complains about it or brings ther printers back, so it can't be too much. As for our own machines, they are all lasers, and I can honestly say we have never had a blocked print head on any of them.

 

[Pradeep]

Sorry this is a little OT, but how do color laser printers compare to the newest inkjets?

How about thermal printers? They are supposed to be much cheaper to run than inkjets I thought.

Pretty good, though they can't compare to a 6 colour inkjet for photolike quality. At least the entry level US$1000-2000 models can't. Also the cost of four toner carts is not cheap, tho I guess the cost per page is less than an inkjet. Main benefit is being able to print on normal paper.

Haven't heard much about the thermals (Tektronix/Zerox Phasers). I believe Merc has one. Apparently best suited to colour business documents (pie charts etc).

 

[Pradeep]

Oh yes, one of the major benefits of both laser and thermal is that they have far greater duty cycles than the inkjets. And speed.

 

[time]

Only the very well heeled should contemplate a color laser.

If you use it to print any volume of pictures or graphics (which is the most likely application), running costs are not necessarily that much better than an inkjet. On the other hand, they obviously work far better with laser/copy paper, which is a considerable saving.

What almost everyone doesn't realize is the ancillary costs associated with a color laser (the latest generation seems greatly simplified, but costs seem to still work out about the same). Here's some of the parts that are scheduled as consumables for an HP 5/5M:

Cyan toner bottle    $43 (3000 pages)
Magenta toner bottle $43 (3000 pages)
Yellow toner bottle  $43 (3000 pages)
Black toner bottle    $9 (3000 pages)
Toner collection kit $30 (20000 pages)
Coating pad kit      $57 (20000 pages)
Black developer     $205 (40000 pages)
Color developer     $585 (40000 pages)
Print drum          $360 (30000 mono/60000 color pages)
Transfer belt       $195 (60000 pages)
Fuser unit          $275 (not stated)

All prices in USD. Toner-related page estimates are usually based on 5% per color or 15% total page coverage.

Putting it all together gives 8c per page.

In comparison, consumables for the Epson C80 inkjet printer:

Cyan ink cartridge    $13 (420 pages)
Magenta ink cartridge $13 (420 pages)
Yellow ink cartridge  $13 (420 pages)
Black ink cartridge   $29 (870 pages)

Or 12.5c per page.

 

[time]

It seems to get clogged after long periods of inactivity, or after printing with thick paper.

What's a long period of inactivity, Steve? Pradeep reckons in days, but I imagine it's worse with aftermarket inks, combined with the really small nozzles his has.

 

[SteveC]

It seems to get clogged after long periods of inactivity, or after printing with thick paper.

What's a long period of inactivity, Steve? Pradeep reckons in days, but I imagine it's worse with aftermarket inks, combined with the really small nozzles his has.

A long period would be a few weeks. The Photo 780 is a 4 picoliter printer, which may explain the difference in the frequency of cleaning.

Steve

 

[Cliptin]

What almost everyone doesn't realize is the ancillary costs associated with a color laser...

Lets assume there are two classes of customers. Those who print only a little, and those who print a bunch. Keep in mind that both of these printers come OEM with ink and a one year warranty.* We need to have a common time frame to work from and the warranty period is a good one. In actuality the numbers are relative and it doesn't affect the outcome unless you consider that an out-of-warranty inkjet will die before a out-of-warranty laserjet.**

I have based my projections on a LJ5 purchase price of US$400 (ebay) and a C80 price of US$149 (MSRP) plus the list of consumables provided by time. I also assumed the use of paper that can be purchased for US$5/500 sheets. Be aware of the quality of prints that are typical of this quality paper.

Based on my calculations, I can show that until the consumer prints 1990 sheets the inkjet is the more economical buy. In order to print that many sheets ,within the warranty period, the consumer would have to print 5.4 pages every day. Further, based on the information time provided, a set of toners will last 3000 copies. Those who do not print a massive amount may never see the second set of toners before the HP printer goes out of warranty. In order to run out of toner (3000 sheets) at about the same time that the machine goes out of warranty you would have to print an average of 8.2 pages a day every day for the entire year. These folks will need no consumables other than paper for the laserjet. If the consumer continues to print up to the 3000 page mark before they retire the printer at the end of the year, they will have saved US$227.

There is a small range between 3000 and 3130 sheets when the inkjet will be more economical. This is due to the much higher cost of the laserjet toner. The maximum cost differential is US$11.

I had originally calculated the break point at 6950 sheets. However this calculation included many consumables that were not consumed until well after the break point. While the revised calculation does indicate a break point of 3130 sheets, be aware that the return on investment after 3130 sheets will be influenced by consumables not yet taken into account. In other words, once you get into the 20,000 and 40,000 sheet region you will have to purchase consumables that will eat into your savings.


*I am aware that printers normally come with a reduced size cartridge. I have disregarded this information in order to reduce the number of unknown variables.

**Even if you consider that an out-of-warranty inkjet will die before a out-of-warranty laserjet, you should not be concerned because printers normally do not wear with time but with use. The number of pages at which the inkjet is at its most economical is well within the ability of the printer; but beware to heed the recommended duty cycle.

 

[Prof.Wizard]

If you print less than 20 pages a week I don't think a Laser Printer justifies the initial costs. I personally print even less in cases I don't have a paper to deliver...

 

[jtr1962]

Looking at the maintainence schedule for typical lasers, it is likely that the only consumable the average home user will need to replace are the toner cartridges. Most of the rest of the items are scheduled for 20,000 pages and up. Assuming you use the printer for 5 years, that's 11 pages per day, or 4000 per year. I don't think most home users print even close to that. Assuming you can afford the $2000+ price for a color laser, that will likely be your only expense for the first year or two.

Regarding the other items, although scheduled to be replaced at a certain time, I would wait until there was a noticable decline in print quality. Since most homes are a good deal cleaner than offices(at least ones I've been in), it is reasonable to assume you could perhaps get a bit more life out of print drums, belts, and the like. No doubt occasionally opening the printer and cleaning the moving parts if they need it would prolong the life.

It would be interesting to see exactly what chemicals the developers and toners are to justify the high prices. If lasers were more popular, we would probably have cheaper generic replacements for those.

BTW, I've been using refill kits for my Deskjet 940c with good results. Thus far, the print quality on cartridges I've refilled has been indistinguishable from OEM. The downside is that the cartridges don't register as filled, so my printer software perpetually says I'm low on ink. I'm careful enough not to buy those stupid, generic all-in-one refill kits, but instead get ones designed specifically for my cartridges. No problems with clogging nozzles so far, either. This was a problem with refills on my Deskjet 400c, however. I also noticed a degradation in print quality as well after about 10 refills.

That remark by Cliptin about dust was also interesting. The 940c has the paper under the output tray, so this partially shields it from dust. In fact, if I were to cover the small space between the paper and output trays, it should eliminate dust. Anyway, the way the paper feeds(face down side gets printed on) pretty much omits the possibility of dust contamination. My brother once clogged the heads on his BJC1000 because he was spray painting within a few feet of the printer, and apparently the very fine(and not 100% dry) mist got on the paper and clogged the nozzles. I was able to unclog them by soaking in lacquer thinner, and refilling the cartridges enough to force ink out of the nozzles. Now it prints just fine.

 

[Fushigi]

I have an HP 722C that I print from maybe once in two months. I've never had a clog problem. Maybe it matters that I don't keep it powered on when it is not going to be used.

Actually, it probably doesn't matter. Our 990 is left on 24x7 and we sometimes go for 2+ weeks without printing. No problems at all with clogging. Heck, it's unusual to hear it do a head cleaning.

After experiencing this fast, silent HP I have to wonder what Epson engineers are smoking. The Stylus 900 (I think that was the model; it retailed for US$399) I had before I bought the HP had awful color print quality on label stock (compared to the Canon 600 it replaced & the HP 990 that replaced it). It was slow (well, a little faster than the Canon but way slower than the HP). Rather loud vs. the HP which is pratically silent. To top things off, it took a long (& loud) time to clean the heads when powering up, even if I used it every day, which I did from time to time.

- Fushigi

 

[Cliptin]

If you print less than 20 pages a week I don't think a Laser Printer justifies the initial costs. I personally print even less in cases I don't have a paper to deliver...

3130 pages is the magic number. If you expect to keep your inkjet printer for no longer than the warranty period (one year), then that comes out to 60.1 pages a week, every week for the year.

If you feel like a gambling man and expect the inkjet printer to last 3 years then you must only print 20 pages a week. Based on the printer's duty cycle (5000pages/month), I think the printer will probably last three years producing 80 pages/month. However the manufacturer will not hold your hand if you are wrong therefor it is a gamble.

PS. The LJ5 is a color laser printer. $400 remanufactured on ebay.

 

[Mercutio]

The LaserJet5 is also approximately 2.5 feet (say, .70m) in any dimension and weighs about 100lbs.

I think they drive cars Europe that are smaller than that.

 

[time]

A few issues with your reasoning, Cliptin:

Firstly, you quote the price for a definitely used HP laser, but talk about it having one year's warranty and assume all of the consumables are new. In reality, the color Laserjets on Ebay are all part of the way through the long life consumables, in some cases enough that the seller has already replaced some. And I could only see one that estimated the amount of toner remaining. It would be rather extraordinary for someone to dump one of these immediately after replacing all the toner, so it's an obvious thing to budget for.

And of course the price of a new color laser would blow your numbers out of orbit.

Secondly, the page life numbers I quoted are only a guide based on minimal page coverage. Just like an inkjet, those numbers shrink dramatically if you use it to print graphics. Again, looking at the examples on Ebay, I noticed a "drum unit" had been "recently replaced" on one, yet there was only 45% life remaining on the drum. I suspect that in fact nearly all of the consumable life expectancies are related to page coverage.

For those considering a second hand color laser, bear in mind that later models have a quite different consumables schedule that appears to shift a lot of the cost onto the toner carts. The current HP 4600 series:

Cyan toner cartridge    $235 (8000 pages)
Magenta toner cartridge $235 (8000 pages)
Yellow toner cartridge  $235 (8000 pages)
Black toner cartridge   $175 (9000 pages)
Transfer kit            $220 (not stated, 25000 pages for HP 4500)
Fuser unit              $275 (not stated, 50000 pages for HP 4500)

Note that all the prices I quoted previously are about 15% too high, but I used the same basis here to make it easier to compare. And the 4500 is quite different from the 4600, but it was the best I could manage from HP's specification vacuum. :x

Anyway, we all have to pay for the new HPQ somehow, and at 12c per page, I guess this is one of the ways. Notice it only makes a bit over 1c/page difference if you don't include the long life consumables.

BTW, the manufacturer will hold your hand if you take out Epson's three year extended replacement warranty for $25. You should probably factor that in as well.

 

[Tea]

What's the deal with Epson's extended waranty, Time? (I probably should already have this info somewhere, as Epson send me all sorts of stuff, but I never find the time to read it all.) Does the user buy it direct from Epson? Or some other scheme?

 

[Cliptin]

I certainly did give the laserjet option a lot of leeway. The point I made, which you seem to have missed, is that you will have to print a lot of pages before the laserjet becomes the optimal choice. All of the variables which you have examined more closely point to an even greater number of pages that would need to be printed before the laserjet becomes the optimal choice.

 

[time]

Tea,

In this country, Epson doesn't exactly go out of their way to push the extended warranty. AFAIK, it's only available through dealers and must be registered with 30 days of purchase (meaning you pretty much have to sell it with the printer).

There's a different product code for the warranty for each printer model, and you need to purchase them like any other stock. If you're not already dealing directly with a distributor, you might need to approach one (but I don't know - I might find out more in the next day or so).

Distributors in Victoria are Alloy, Digiland, Tech-Excel and Tech Pacific.

AUD RRP is $49 for C41, C61 and 810; $79 for C70, C80 and 895. The latter is just extortion given it's USD25 in North America, and I can't see the former adding up for a humble C41.

Still, in my experience Epson honours their warranties, and maybe some C61 customers might spring for it. Some of us seem prepared to pay that kind of premium to get a three year warranty on a hard drive (WDJB). :-?

 

[Tea]

Hmmmm... Thanks Time. I think that some people would go for it, though about 25% lower price would make a big difference. Worth doing for an 810, possible for a C61 ... C41 .. yeah.

We have usually bought our Epsons through Comnet, a rather low-rent mob here in Melbourne that are pissing me off quite a bit lately. Just last week Kristi and I were pondering giving them the flick in favour of Alloys. We like Comnet because our rep works really hard for us, because they are super-quick to ship an order and Leigh will go out of his way to find weird stuff when we need it. Price-wise they are competitive. But their warehouse guys are no good: you'll remember my tale of badly packed Samsung drives, and their RA service leaves a lot to be desired. For printers, this is a non-issue: printers don't need packing and service is direct to Epson (and with Epsons, service is a rarity anyway). But it's the little stuff that annoys me: external USB drive boxes, video cards, stuff like that they frig me about with.

Alloys don't offer me the vast range of odd stuff that Comnet have (though they have a very impressive range of printers, of course) , and I'll have to find someone else who has those excellent Samsung keyboards, but Comnet's warehouse has buggered it up once too often.

 

[Cliptin]

I have discovered that you can dislodge clogs in an HP cartridge by soaking the cartridge in water for an hour and then create a vacuum on the nozzles. Before you try this little trick, let me figure out and tell you how long it takes for the ink to wear off the skin. :mrgrn:

 

[P5-133XL]

I didn't know that HP was using water-soluable ink. My guess would have been to apply the standard non-H2O solvents of rubbing alcohol, terpentine, or finger-nail polish remover with a q-tip and then apply the vacume.

 

[Buck]

I didn't know that HP was using water-soluable ink. My guess would have been to apply the standard non-H2O solvents of rubbing alcohol, terpentine, or finger-nail polish remover with a q-tip and then apply the vacume.

Who uses non water-soluable ink? Would they actually use petroleum based inks like I did on a press?

 

[Cliptin]

I didn't know that HP was using water-soluable ink. My guess would have been to apply the standard non-H2O solvents of rubbing alcohol, terpentine, or finger-nail polish remover with a q-tip and then apply the vacume.

I did try a rubbing alchohol soaked paper towel but it did not seem to be working. As to water solubility, my printed pages always run when they get wet. In addition, the water was changing color as the cartrige was soaking.

This article and the links from it provided some new direction.

 

[time]

Who uses non water-soluable ink? Would they actually use petroleum based inks like I did on a press?

Epson and some wide format manufacturers, and yes, they are also moving into oil based inks.

This site has some excellent information on inks and other printing issues:

https://www.inkzone.com/resource/inksandsys.cfm

 

[Buck]

Thank you for the link Time, that is a good article. I have always disliked the technology of aqueous inks because of their inherent limitations. The VOCs for solvent based inks are an issue too, although I wonder what the impact the small amount used has on an office environment. As a printer, we were in the process of changing our solvent based inks from petroleum to soy. Soy inks require less solvent as a vehicle for administering color. Perhaps this will be used in ink jet printers.

 

[Cliptin]

Soy is tasteless!

 

[Pradeep]

The dpreview.com printer forum talks about the potent fumes/smell emanating from the Epson 2200 and it's ilk. Can't be good for you.

 

[Buck]

The dpreview.com printer forum talks about the potent fumes/smell emanating from the Epson 2200 and it's ilk. Can't be good for you.

I guess after a decade of inhaling large quantities, you get used to it. As a matter of fact, I like the smell of certain inks, especially Toyo and VanSon's CML Oil base.

 

[time]

The dpreview.com printer forum talks about the potent fumes/smell emanating from the Epson 2200 and it's ilk. Can't be good for you.

Probably get you high if you hang around it enough. Desperate people sniff various off-the-shelf products like glue and correction fluid thinner to get a buzz from the solvents.

I guess this means the water cooler will no longer be the office congregation point.