Why are there Lines on my Copies?

You wouldn’t want to spend $75.00 to $150.00 for a technician to come out to just clean your glass, would you?  No, I didn’t think so.

Slit Glass

With the age of Multi-Functional Printers, (MFP’s) comes new problems.  Fax Machines, Digital Copiers and MFP’s all have one thing in common.  They all have an item on them known as the “Slit Glass.”  Each machine that uses a slit glass as a way to scan images will eventually get dirty and cause lines on copies along with transmitted faxes.  These machines don’t scan the same way that older or analog copiers do.  Analog copiers use the entire glass with mirrors to get the image to the Photoconductor.  Digital copiers use the slit glass.  It passes along this small area and uses mirrors that direct it to the CCD unit.  The CCD unit then converts the analog information into digital information.  When using the Document Feeder or Processor the original only passes over the slit glass.  It does not get copied from glass where you lay down your original.

How to Determine if the Slit Glass is the Problem.

On Copiers, MFP’s and Fax Machines you can quickly diagnose if the slit glass is the problem. 

Copiers:

First make a copy on the glass.  If there are no lines showing, then make a copy through the Document Feeder or Processor.  If there are lines on the copy then more than likely it is the Slit Glass causing the problem.  I say more than likely because there are occasions where this may not be true. 

Fax Machines and MFP’s:

First print a journal or a function list.  To print these refer to your Operators Manual.  If you don’t have a line, make a copy through the Document Feeder or Processor.  If there are lines then your problem is the slit glass.

Digital Copiers and MFPs

This type of slit glass is easy to spot.  Just lift the Document Feeder up and look for the small rectangular glass around 1 inch by 12 inches.  Look at it carefully.  If there is anything stuck on it, this will cause a line. The Image defect will look like a small pin sized line all the way across the page, although I’ve seen larger even 1 inch wide.  The most common substance that I have found stuck to the glass is white-out.  This happens because they don’t let it dry well before running it through the feeder.  When it dries on the glass it doesn’t come off easily.  Another issue is blobs of ink, again this is because of not allowing enough time for it to dry.  Being impatient actually will cost you more time in the long run.

Cleaning the Slit Glass.

Cleaning the slit glass is easy but you need to pay close attention and be sure that you have removed all of it.  Take your finger nail and scrape off as much as you can.  Get a cotton towel and saturate it with alcohol.  I also recommend using an alcohol swab.  These come in little sealed pouches and are inexpensive and easy to find.  Let the spot soak for a minute and this will loosen up the white out.  Glass cleaner does not remove it as good as alcohol.  There is something about alcohol that breaks down the white out.  Next, go over it with a lint free cotton towel soaked with glass cleaner, and then dry it off to eliminate streaks.  Never spray the liquid on to the glass because some of it may find its way inside the machine.

Fax Machines.

The slit glass on a fax machine may be a bit harder to get to.  The document feeder or processor is normally under the control panel.  Lift up the panel and shine a flash light on to the small slit glass.  It is about 1 inch by 12 inches in diameter.  Use the same technique to clean it.

You Cleaned the Slit- Glass but the Line is Still There.

Some times the blob of white out is really stuck on the slit glass. I have a procedure that is fool proof in finding where the spot is, because sometimes it is so small that you can’t see it.  First, get the copy that has the line on it.  Hold it directly and evenly on the slit glass.  Look carefully and see if you can follow the line to the glass.  This is where the spot is.  One thing about this procedure.  You must check it both ways.  Turn the original 180 degrees and inspect it again because the image is reversed because of the lens.  Now that you have found the spot you may have to use a solvent to get that spot off.  These can be stubborn and difficult to remove.  You can try WD-40.  My technicians use a solvent called D-Ink (Coopers).  D-Ink is very expensive but it works well.  If you still have the line on your copies then you have another problem.

Calling for Service

 Call a qualified repair person to come out and take a look.  I recommend using a local independent repair company.  Look them up in your Yellow Pages.  I recommend an Independent because they usually are a smaller company and they will give you more personalized service.  I hate those crazy phone systems, being stuck in a loop when trying to call for service.  Most of the time they also have more experience and you won’t be paying for over- inflated hourly rates of an authorized dealer or huge corporation.

Other Line Problems

If you followed my tests and you have a line both copying from the glass and using the Document Feeder then you have another problem.  I believe that it is always a good idea to have a good technician ready to call, but why spend money when it is something so simple anyone could do it.  Here is a list of probable causes.  Many things could be wrong so I am not going to go in too much in detail. 

Possible Causes / Lines

Laser Printers, Laser and LED Fax Machines

Toner cartridge, Charge roller, paper or object stuck inside blocking the scanner, transfer roller, optics, and corona wire.  Note: You can clean these but if you don’t know what you are doing you can damage something.

 Inkjet Printers and Fax machines

Print head, Ink cartridge, dirty optics, paper or object stuck up inside machine blocking the print-head or optics.

Copier and MFP’s

Toner cartridge, Charge roller, paper or object stuck inside blocking the scanner, transfer roller, corona wire, and dirty optics.  Note: You can clean these but if you don’t know what you are doing you may damage something.

I hope this article has helped you save some of your hard earned money.  There really is no reason to spend money when you can just clean it yourself!