Originally posted by caliscouser Originally posted by Not a Number Since that (Californian) person's main business seems to be selling used parts from cameras including Pentax DSLRs it is just as reasonable to conclude the repair he makes is to replace the solenoid with those taken from other Pentax bodies.
No I don't think so. A few people on here have reported that the repair from this vendor has failed after a few months.
It is a shame that we cannot peep into one of those Pentaxes he repaired
Originally posted by caliscouser Plus their own website states "This repair includes a modification of the aperture control block", a 'modification'. Later they state they don't do a 'replacement' like Pentax official repair as they believe it will fail again.
Sounds very strongly that he either files the horseshoe or he uses the soldering method.
---------- Post added 02-03-18 at 03:30 AM ----------
Originally posted by Rob-48 Originally posted by Tonytee My Pentax k-50 has 3,403 shutter activations.
Date of Birth: 1/20/2016.
Serial Number: 6096174.
Tonytee
My research suggests that the failure is a function of 'age', rather than of 'number of photos'
Neither nor!
It is more a question of (low) shutter activations and not using the Pentax often enough.
Several reasons for this:
1. The green solenoid has a stronger holding force
2. The green solenoid is made out of cheaper material (plastic and metal used for the horseshoe*)
3. This part which guides the movement of the horseshoe has more play
4. The horseshoe does magnetize (and de-magnetizing does NOT help)
The combination of those factors result in the horseshoe remaining stuck.
The filing method helps against the too strong magnet, but it does not help against the cheap materials and play.
One could compare this with bearings: A good bearing has lowest possible friction and lowest possible play.
This solenoid is a combination of all those factors. Through the filing method (or the soldering method) the horseshoe cannot be guided as well
anymore in the housing and tilts more towards the right side where the mechanism acts on. The horseshoe has MORE PLAY now! This tilt can finally result in the horseshoe being stuck again.
A little better solution would be the use of a weaker magnet, but this does not eliminate the other negative factors and it cannot solve those
*problems due to bad material:
- I have found corrosion on some horseshoes.
- I have found damage to the inner lining of the plastic of the body in which the horseshoe moves.
So DIY by using the white solenoid is the only option. Or finding somebody who repairs and guarantees that he uses the white solenoid!