Tag Archives: Fix

Pentax K-30 / K-50 Black Picture Problem and Fix (Aperture Control Block)

Pentax K-30 and K-50 have a problem with the aperture control block mechanism within the camera that causes them to not actuate the aperture, hence giving only black photos. This is due to a small solenoid within the camera, that over time becomes more magnetized and fails to actuate.

The fix is simple: take out the moving horseshoe part from the solenoid and then file or grind it down to reduce the magnetic force imposed on it at rest. The filing works because it reduces the effective contact area at rest, hence reducing the amount of magnetic flux lines going through it.

This post is an addendum to the very useful video posted here by MBS TV. This will show you how to open the camera and also a good technique on saving the screws.

What the video doesn’t show you is how to do it for a K-30 nor how to extract the solenoid. To extract the part on the K-30, there are two tricks missing in the video:
• Unscrewing the solenoid: You should use the bit of a multibit screwdriver to access this. Normally there should be enough clearance and once the glue is removed, you can remove it by hand.
• Taking the solenoid out: You need to bend the top cover case slightly and simultaneously use a pair of tweezers to extract it.

Once it is extracted, you can grind it down. I have shown an example of the ground down part here. Remember to reassemble and test the camera before putting the case back on.

Photo 1: Unscrewing the solenoid. Note the screwdriver bit which comes from a mobile phone screwdriver set. If you search Amazon for this, you should find one. Also, you’ll probably find it handy for opening the camera in the first place.

Photo 2: Extracting the solenoid means you have the carefully bend the top cover by applying force as indicated by the red arrow.

Photo 3: Photo of the actuator in the solenoid once round down. you can see that grinding down the tips are the most important thing to do in order to reduce the magnetic flux going through the horseshoe.




Fix for Epson R3000 Ink Smearing / Dropping on Prints (Also works on R3880, R2880, and others)

A common problem with the R3000 (and other Epson printers that use the same print head), is that after a couple of years of service ink drops begin to fall on your prints. This is not due to a head strike, but actually due to with the PK/MK switch within the ink supply unit that gets blocked over time. After a while, especially if you use Photo Black (PK) only, such as myself, the MK line will block at the switch and then start leaking black ink.  This process will work for any other Epson printer with a PK and MK ink switch, i.e. 3880, 2880, etc.

UPDATE: Another user has confirmed that this works for the R3880. Great!

One solution is to switch to MK and then cut PK cartridges to fit into the MK hole – but this is hardly satisfactory. Another solution is to replace the entire ink supply unit, but this costs about 200 EUR and is labour intensive.  A final solution that I have tried (and works!) is to perform a complete line clean on the R3000, using refillable cartridges. The total cost is going to be for a set of refillable cartridges (~25 EUR), some flushing liquid (~25 EUR) and a set of cartridges (2 x PK + MK, i.e. about 100 EUR). Note that the cost of the cartridges you will require anyway, if you do perform an ink supply change.

Here is how it works:

  • Ensure you have a couple of days where you don’t need to print and a set of PK and MK cartridges in the printer at least 50% full, and as a minimum one new set at hand.
    • The 50% full ink cartridges will allow you to perform the PK / MK switch if you have a problem with your refillable cartridges.
    • You will need at least one new set of cartridges to recharge the lines and the supply unit. I would recommend two as a minimum.
  • Buy a refillable R3000 cartridge set and solvent cleaning set. I recommend the following (or similar):
  • Load the PK and MK cartridges with cleaning fluid. Load them into your printer. Store the original PK and MK cartridges in plastic cling wrap, making sure that you have covered the ink outlet holes and the whole cartridge.
  • Perform multiple ink changes between MK and PK. This will charge your PK and MK lines with the cleaning fluid. I would do this for a whole refillable cartridge capacity. Reload them and perform the switch again.
    • Perform intermittent print head checks to see if the lines are being flushed. You should see the full black head starting to get lighter and lighter until it becomes transparent (for PK and MK).
    • Open a word processor and print a page full of full black. You should see the print getting successively greyer and greyer. It should be somewhat grey at the end (due to the R3000 mixing other greys to print black), so remember to use the print head check to verify it is fully flushed.
  • Wait for 2 days. Switch to the other black ink. Wait for another 2 days. (i.e. leave the switch on each black colour at least 2 days on the cleaning fluid).
  • Perform another print with the word processor on full black. It should now be clean.
  • Unwrap the real PK and MK ink cartridges. Reload them into printer and perform a switch between PK and MK to charge the lines. Note that you will need about 20ml of ink to recharge the lines.

Epson sells a software utility for the R3000 to prime the lines to feed ink back through them. If you don’t have this tool, then you should use between 3-5 head cleaning cycles to do the same thing (one for PK and MK).

At this stage, the R3000 should now be fixed and no longer be dropping ink. Change to new PK and MK cartridges when ready.  Congratulations, you have just saved your printer! (Well, at least it worked for me …)

p.s. Do NOT use the syringe directly into the feed line — even though this may be recommended on some sites. This is for small format printers only, and if you do this, you may blow the lines into the supply unit permanently damaging the R3000.

Before Fix: Ink drops on prints due to problem with PK / MK switch. These are not head strikes.


After Fix: No more ink drops on prints!