Epson 4990 scanner. Help with glass platen cleaning needed!

[rayfoxlee]

I have just bought an Epson Perfection 4990 scanner for medium format scanning to replace my very old, but serviceable 2450. Not surprisingly, the inside surfaces of both glass platens need cleaning – I know this is a frequent problem with most flatbeds and I have successfully cleaned the glass on the 2450 a couple of times. The 4990, though, is a bit more challenging! With the experience of the membership here on RFF being so wide, I am hoping someone can help me out, please.

The glass platen in the lid is the unfamiliar part to me and although I have the exploded view diagram from betterscanning.com, I don’t want to cause any damage – despite the modest cost of the scanner! Can anyone who has cleaned one of these machines help with some advice, please, as there is nothing on the web that I can find that covers cleaning this part of the machine?

• In particular, should the lid locking mechanism be on or off for removal?
• The plastic surround for the glass is secured by 5 screws – should all 5 be removed or are some screws securing part of the internal mechanism that can be left in place?
• On the outside front of the lid, there is a strip of plastic bearing the Epson name. Does this need to be removed? There appear to be plastic lugs, which look similar to those securing the top part of the lower base unit to the floor pan.

Whilst on this topic, as far as cleaning the glass platen on the base unit is concerned, this looks a similar process to the 2450, but is there anything to particularly watch?

Hope to hear a few thoughts. Many thanks in advance!

Issue now resolved 1 Nov 2018. Separate post details steps to clean both glass platens.

Ray

 

[rayfoxlee]

Is there no-one who has successfully opened up the lid? No service manuals on the web, nothing apart from the exploded view on betterscanning.com.

Ray :bang:

 

[rayfoxlee]

Having just posted the piece above, I've succeeded in removing the cover to clean on the inside of the glass platen.

If anyone is interested in doing this job themselves, let me know and I will post instructions.

Ray

PS. It pays to be danged stubborn and persistent! 😀

 

[grooves1200]

I'd love to know -- was never able to get those "hidden" screws out to fully clean things.

 

[peppard]

Good job!
Please, post instructions, as I am in need to do the same procedure.

Thanks a mill,

Giorgio

 

[Lou Iaquinto]

Me too Ray.

Regards,

Lou

 

[rayfoxlee]

Instructions to clean a 4990 scanner

OK, let’s start with the lid. This is where the main dust problem was inside the glass with my unit.

Try to work in a dust-free room if possible – a tiled bathroom (without carpets!) is ideal, after running the hot shower to clear the air. Let the steam dissipate.

1. Turn-off the power supply to the scanner and unplug the mains lead and the supply to the lid.
2. Lock the lid by moving the slider to the right to lock. Pull the lid upwards to remove and lay on a flat surface on the lid top (glass uppermost). Now unlock!
3. The dark grey insert holding the glass platen is secured by 5 screws and 8 plastic tabs – all visible. Remove the screws and keep safe.
4. The 8 plastic tabs (2 on the front curved part of the lid and 3 down each side) can be seen in the small rectangular recesses or slots. Take a smooth flat screwdriver that will fit in the slots or a small round edged implement and, starting at the front of the lid, gently prise up the dark grey cover by just enough to pop the lugs free. The edge or rim of the outside of the lid cover is very flexible and is designed to flex sufficiently to allow this without damaging the parts. If the front silver plastic strip with the Epson name starts to work loose, this is simply held in place by snap-in lugs and can be removed, although removal should not be necessary to get the dark grey part off.
5. Prise up the other 6 tabs. By this time, the grey plastic insert should be clear at the hinge end of the lid. Carefully lift it clear of the lid, making sure that the scanner light source does not lift up in the process – this might happen if you have forgotten to release the lock fully. Using your fingers keep the light source unit in place – don’t move it down the guide rails, if you can avoid it, as the position is important on reassembly to ensure that the lock works correctly.
6. You can now clean the underside of the glass. The Epson repair manual for the 4870 says use a soft clean lint-free cloth, but you may have to use a glass cleaner or methylated spirits dilute 50/50 with pure or distilled water for stubborn marks. DO NOT WASH as the glass is held in place by adhesive tape! Use soft kitchen paper towel to wipe clean – you may have to do this a few times. To examine your work, get down to eye level with the glass placed on a dark surface (black paper) and using a light, see if it needs further cleaning.
7. Using a blower brush, give the glass a blast of air.
8. Now clean inside the lid shell. Hold the light source unit in place and clean with a blower brush to remove debris from inside the case. If you can turn it onto its’ front edge whilst still holding the light source in place, this prevents dust falling back into the shell. Cover it with a piece of paper or card to stop airborne dust from getting in.
9. Reinstall by locating the dark grey plastic glass surround’s front lugs into the slots in the front of the lid. Press all down to locate them correctly.
10. Now lock the lid again before installing – but remember to unlock before using! Make sure that the lock fully engages – if the light source unit has moved away from its’ normal resting position, the lock may not engage. After releasing the lugs again, move it back and try again. When all is OK, reinstall the five screws.
11. Set the lid safely to one side after the outside of the glass has been given a clean.

Now deal with the base unit.

1. Lock the lid when moving the unit.
2. Unlike previous Epson models, it seems that Epson have modified the way the top is secured.
3. The cover with the glass is held in place by 4 screws – 2 under silver plastic caps on the surface and 2 deep in the hinge recesses. To remove the plastic caps press down a piece of duck tape onto each cap and leave for a few minutes, then quickly pull the tape off – this should remove the caps without damage. Remove all the screws.
4. The front part of the base unit is the part with the scan button, light and the words ‘Epson Perfection 4990 PHOTO’. This part needs to be removed to proceed. It is held in place by lugs at the bottom (you can see them by looking down into the machine through the glass towards the front) and side tabs. You will need a slimmer implement to prise the bottom part up to release the lugs. This will also release the side tabs. It is fairly flexible. You can now lift this clear.
5. Now release the lock!
6. From the back of the base, carefully start to lift the top clear – BUT BE CAREFUL as the light source and sensor unit may start to lift with the upper part. Whilst lifting the top, with the fingers of one hand gently lower the unit back into its’ resting position if it does start to lift up with the upper part. Also note that an electrical cable from the unit is secured to the inside of the upper part to power the on/off button and light. Don’t unplug this, as the top can be placed upside down alongside the base whilst still attached by the lead.
7. Now clean the inside of the glass using the same process.
8. When the glass and inside the base is clean, reposition the top on the base, by locating the front edge first and lower towards the light unit. You may have to use your fingers again to gently lift the light source unit to clear the locking mechanism. Now secure with the screws and the screw caps.
9. Lastly, replace the front nameplate by securing the lugs and tabs in the reverse way to removal.
10. Remember to unlock before using!

JOB DONE! 🙂

 

[Lou Iaquinto]

Many thanks Ray,

I've had mine for 11 years. It needs a clean!

Cheers,
Lou

 

[Nokton48]

Thanks Ray!

I just bought a 4990 for scanning my large format. I think this will work well for me, for 9x12/4x5, 5x7, and 8x10. Waiting eagerly for it to arrive.

Invaluable information here.

-Dan

 

[paulcerv]

There is a Youtube video where someone shows how to disassemble the scanner and drills out the plastic screw covers because the suggestion of using duct tape did not work. Same problem here, however I found that hot glue works perfectly and is easy to remove after applying. I took a bic pen, removed one end and put a small dab of hot glue around the rim of the plastic. Set is on the tab for a minute to harden and pulled up to remove the plastic cover. The hot glue just peels off after.