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Forgotten elements of Total Cost of Printing – Reliability – Part 4b, Laser supplies failures

Issue #1003/1 – Laser printers and toner supplies are generally perceived as being much cleaner than inkjet printers and ink supplies. But, is this true? We show that just as much mess (if not more) can come from defective toner supplies and that costs associated with them are considerably higher than costs associated with defective ink supplies.

Typical faults and problems associated with toner supplies also fall into two broad categories: leaking toner and imaging unit damage.

Specific problems we have experienced in recent years revolve mainly around leaking toner, both from the cartridge itself and from the waste toner container on a separate imaging unit, which filled up and overflowed before the imaging unit life had expired.

Cartridge faults
Leaking toner is not as unusual as one might imagine. Almost any user of laser printers will have experienced a smattering of toner escaping onto the inside covers of the printer itself or onto their desk as old cartridges are removed and new cartridges inserted.

However, this is, in itself, not a great problem – a quick wipe once the cartridges are safely stowed in their respective receptacles (cartridge packaging and printer). Where there is a problem is if the toner manages to leak within the printer and find its way onto the printed page. This may occur if any of the seals in the cartridge are providing inadequate protection.

In the series of photos below, excess black toner is escaping from the toner hopper and onto the developer drum. The trouble is that there is too much toner on the developer roller in relation to the electrostatic image on the OPC drum. So, the toner scatters, falling indiscriminately onto the drum or other parts of the printer. Inevitably, this toner will find its way onto the page and will be fused to the paper as the page is ejected from the printer.

Leaky toner 1Black toner leak inside laser printer

Because it is black toner involved here, it is not easy to see against the dark insides of the printer. The left hand image was taken without flash while the central and right hand images were taken with flash. They show the leaked toner in different ways and how it has accumulated on and around the imaging drum.

Showing how unacceptable a print is when toner is leaking in this way, the images below show severe thickening of all the black parts of the image, together with smudging around and amongst the characters and a general black smudging all over the page, caused by the black toner fault. Compared to a good print of the test page, the fault is very obvious.

Leaky toner 4Effects of leaking black toner

In the next set of images, yellow toner is escaping from the toner hopper and accumulating around the developer roller. The left hand image shows the developer as it should be, with an even coating of toner, while the middle image shows the excess toner that had accumulated after only 20 pages had been printed. The right hand image shows the toner once tipped out onto a clean sheet of paper.

Leaky toner 2Yellow toner leak around developer roller
Toner blobBlobs of yellow toner
find their way onto the page

Excess toner like this rapidly escapes onto the drum and the transfer belt and then onto the page itself, causing unsightly colouring on the page. In these next images, we see how these two faults show themselves on the printed image, the result of printing only 70 more pages (total 100 pages).

Yellow toner smearing can be seen in patches along the length of the page (yellow not visible enough in a scan of the page, so not shown) but also showing clearly how lumps of toner have fallen onto the transfer roller. This page would be totally unacceptable as a top quality print.

So, how can we apportion costs to this type of fault?

First of all, what we have to accept is that when a fault of this nature develops there will be time wasted in attempting to clear the fault and obtain clean prints. The length of time taken may depend on both the experience and the stubbornness of the individual involved.

An experienced user will recognise that this is a fault that cannot be rectified with any simple cleaning procedures and that the only remedy is to replace the rogue cartridge. An inexperienced user, on the other hand, may spend as much as a half hour removing the cartridge, inspecting it and the inside of the printer, cleaning the cartridge and its surrounds, replacing it and trying to print again – only to find that the fault is still there.

So, to be realistic about costs, we have to include both time and a new cartridge (meaning the cost of the portion of the defective cartridge that has been wasted) in the cost calculation. For the purposes of this illustration, we will assume that 50% of the toner has been used and 50% wasted.

Leaking toner cartridge

Time to diagnose problem 10 seconds
* Remove & inspect cartridge 30 seconds
* Clean and replace cartridge 1 minute 30 seconds
* Return to desk to print test page 1 minute
* Inspect test print 10 seconds
Repeat process * 4 times before giving up 12 minutes 40 seconds
Time to diagnose and resign to problem 16 minutes
Cost of investigations @ €50/hr €13.33
Order new cartridge say 10 minutes
Receive and install new cartridge 5 minutes
Time to reprint spoiled pages 1 minute
Time to order and install new cartridge 16 minutes
Cost of buying new cartridge @ €50/hr €13.33
Cost of toner wasted in faulty cartridge
@ say 50% of new cartridge cost
say €50
Cost of wasted pages – say 10 @ €0.075 €0.75
Total cost to resolve problem €77.41
Potential printer downtime ~24-48 hours

Note: Cost of time at €50 per hour is based on cost model outlined in article .

Overall, printer downtime will depend on the availability of a new cartridge – is there another cartridge waiting in the store cupboard or does one need to be ordered? If there is a new cartridge ready and waiting in the cupboard, there may be justification for deciding that there is no cost involved in acquiring a new cartridge because a replacement can be ordered up in due course as part of the general administrative process. But, even then there is an unplanned cost involved in collecting the toner from the cupboard and installing it.

Even if we assume no toner is wasted in the faulty cartridge (because it is close enough to end of life to be written off), the cost of determining the nature of the problem and arranging for a new cartridge, outside of the normal course of administration, would still be in the order of €20. However, the counterbalance to that is that the total cost of a cartridge failure early in the life of the cartridge could be much higher than the €70 in this example. No doubt a complaint to the supplier would follow but remember, making a complaint has a significant cost in terms of time that could easily exceed the value of obtaining a replacement under warranty! (There is definite ‘satisfaction value’ in obtaining the warranty replacement though!)

Waste toner / imaging unit faults
Firstly, if a waste toner container, that is an integral part of the laser printer imaging unit, fills up and overflows, the result is one almighty mess that not only spoils the inside of the printer but very quickly finds its way onto the printed pages, rendering them unusable. The accompanying photos illustrate what that mess can be like. There was no software or control panel warning that the container was full and no clear indication of what the exact problem was when the printer cover was opened. Only after a significant amount of wasted time was the precise nature of the problem diagnosed and a solution possible, during which time print jobs were wasted along with the paper and toner – plus the time that inevitably goes with wasted print jobs and having to reprint those jobs.

Toner mess 1Toner mess from overflowing
waste toner container

What I should have done at the time was to phone the manufacturer and ask whether the unit was covered by warranty for this sort of a fault. But in the middle of a test program this wasn’t really feasible. In addition, the page count of the imaging unit was near end of life, so it was just changed and the end of life page-count logged. I have since been able to determine that this fault is probably not covered by the warranty unless it occurs very early in the life of the unit.

Toner mess 2Toner mess on inside of printer
from overflowing waste toner container

However, the point here is that the printer should have had a sensor to indicate that the waste unit was full – but it did not. By the time the problem had occurred, the machine had to be cleaned out anyway, so changing the unit was almost incidental.

Cleaning out a laser printer is no quick task. At least an hour was spent carefully vacuuming out the spilled toner and brushing the surfaces to extract as much of the runaway toner as possible. A further 40 minutes was subsequently spent online with the manufacturer’s chat support line, with no clear solution or explanation as to why the fault occurred, just the recommendation to ‘clean the imaging unit’! Even the product manual only offers the options of cleaning inside the printer or replacing the imaging unit! Not satisfactory.

Overall then, the cost of this fault was (not including purchasing a new imaging unit as life was running short anyway):

Leaked toner inside laser printer

Time to diagnose and test (as above) 16 minutes
Time spent accessing online support 40 minutes
Time to clean inside printer 1 hour
Time to receive and install new imaging unit 5 minutes
Time to reprint spoiled pages 1 minute
Total time spent rectifying the problem 2 hours 2 minutes
Total cost of time @ €50/hr €101.67
Cost of phone calls €2.00
Cost of wasted pages – say 10 @ €0.075 €0.75
Total cost to resolve problem €104.42
Potential printer downtime (with next-day delivery) ~24 hours

Note: Cost of time at €50 per hour is based on cost model outlined in article .

In this instance, it is not so much the failure of the unit that adds cost, because it would have needed replacing soon anyway – hence not including the cost of ordering, buying or installing the replacement unit. Although I may have lost a small percentage of the life of the unit, the major cost is in diagnosing the fault and cleaning the inside of the printer.

Just supposing the fault occurs early in the life of the imaging unit and it turned out that the manufacturer would not accept liability under the warranty, then the added cost here is around €250 for ordering, buying and fitting a new unit!

Furthermore, as there appears to be no way of preventing this fault from occurring again, and the only indication of the problem is when the printed pages become dirty (by which time it is too late and a full-blown clean-up is required anyway), then the cost of cleaning could be repetitive – say once per year over three years = €294.75.

OPC imaging drum damage
Just a brief comment regarding OPC imaging drum units in laser printers. Damage to these units can occur if they are not handled correctly and carefully or if cheap paper is used in the printer.

Many users do not realise that the OPC drum is quite so sensitive and they may place a toner cartridge down on an inappropriate surface, allowing the drum to come into contact with foreign materials, or touch it with their fingers. This can cause scratches, marks or grease spots on the drum that then appear as artefacts on the printed pages.

In addition, dust from poor quality paper, and/or paper with a coarse surface, is also a source of potential drum damage as it causes abrasion to the drum surface during its rotation cycles.

When this happens, and if the damage is causing unacceptable marks on the printed pages (for instance, making them unsuitable for sending to customers) then the only remedy is to replace the toner unit or imaging drum – depending on the supplies configuration involved. This results in cost being incurred before the rated life of the unit is expended.

Where single-piece cartridges are involved, there may also be a high proportion of toner still remaining in the discarded cartridge that is inaccessible to users and is therefore wasted.

Needless to say, users really do not wish to have to discard a toner or drum unit early due to damage of this nature.

Cost implications do not just include the lost life of the drum and wasted toner in the cartridge but may also include attempts to reduce the effects of the damage by cleaning the drum or vacuuming out the paper path within the printer. This process would probably take around 30 minutes, thus adding €25 to the cost of printing every time it is necessary. While vacuuming loose dust out of a printer is clearly a good move, the damage is already done to the drum and, unless either handling is improved or a better quality of paper is used, the problem is more than likely to return.

Use of third party toners
While any third party remanufactured laser supplies item can experience exactly the same symptoms as OEM items, the scope for failures to occur are magnified, depending largely on the skill and integrity of the remanufacturer.

One of the primary contentions of the third party industry a couple of decades ago was that the imaging drum contained within a single-piece toner cartridge could be expected to have a life expectancy of at least two to three times the official OEM life expectancy rating. Thus, the cartridge could be refilled a couple of times without degradation in print quality. In today’s business environment, branded remanufacturers tend to insist on the drum being replaced as a matter of course because they recognise the dangers associated with reusing a drum, the paramount importance of print quality and the threat to their business if customers are unhappy with the overall quality of their products.

This principle also rolls over to the other mechanical parts in the cartridge as well. There may be the need to replace most of the mechanical parts, including wiper blade, doctor blade and developer roller, in addition to the OPC drum. This involves the complete disassembly and reassembly of the cartridge once cleaned.

If these items are not replaced when they should be, or the cartridge components are not cleaned thoroughly and correctly, print quality is sure to suffer and the integrity of the cartridge is in jeopardy, potentially resulting in increased potential of leakages occurring.

Every refilled or remanufactured cartridge (toner or inkjet) that fails or leaks for any reason has three probable effects. First of all, it incurs additional, unplanned and unnecessary costs for the user. Secondly, it reduces the user’s faith in the supplier of the cartridge and, thirdly, it damages the reputation of the OEM printer manufacturer!

I say this because a user rarely distinguishes between the OEM and a supplies remanufacturer to the degree they should. It should be obvious that a problem arising from the use of third party supplies is not the fault of the OEM. But, by association, because the printer hardware itself has been manufactured by the OEM, in the mind of the user there is frequently an apportionment of blame towards to the OEM as well as to the third party supplies remanufacturer.

In summary then, it must not be assumed that the only printer failures, and the only costs arising from a reliability issue, involve only the printer unit itself. Printer supplies are just as vulnerable to failure, depending on the quality of the design and of the manufacturing (or remanufacturing) processes involved.

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