Cleaning fresnel focussing screen

Discussion in 'Camera Building, Repairs & Modification' started by Zuikopath, Apr 28, 2010.

  1. Zuikopath

    Zuikopath Member

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    I have an old Spotmatic SP which has a pretty grubby focussing screen - is it possible to clean fresnel screens or should I be on the lookout for a replacement...?
    I thought I would ask the question before I take it to bits and have to wait a while for a suitable part.

    Cheers
     
  2. ic-racer

    ic-racer Member

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    I know a good way to turn it white. Clean it with 90% isopropyl alcohol (ask me how I know :sad: )
     
  3. richard ide

    richard ide Member

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    Try a very small amount of lens cleaner and a Qtip. Won't do any harm.
     
  4. paul ron

    paul ron Member

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    I have been trying for a long time to get em clean but it seems no matter what I use it only gets worse.

    Recomendations... untrasonic clceaners? A friend in Ga told me he uses it and works wonders for him. I don't have one of those expensive cleaners so I cna't tell you how good it is.

    But I can tell ya this... After playing with my old stereo records this week in an effort to get em cleaned of 30 years of sitting around, I was thinking maybe a good record restorer may be just the thing. Soundguard and another product D4 is suposed to work wonders to remove old dirt from the tiny grooves of a record n leave no residue so why not try it on our focusing screens?

    AS someone mentioned above.. DON"T USE ALCOHOL... it will turn the screen white. Ask us how we know?



    .
     
  5. richard ide

    richard ide Member

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    Another idea: If the screen can be removed; take it to a jewellery store and ask them to clean it ultrasonically (water base cleaner only).
     
  6. wiltw

    wiltw Subscriber

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    I have taken focusing screens and run water over them, then put a drop of dishwashing detergent on the screen, rub around very gently and rinse under running water without further touching. Dip into distilled water (tap water is too full of minerals to air dry spotlessly) and stand up on edge to dry...Do NOT wipe with a cloth to dry, as the 'groundglass' finish of plastic screens can easily be marred and the cloth leaves lint.
     
  7. Zuikopath

    Zuikopath Member

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    Thanks for the help - I will dismantle it and have a careful look. I was aware that they are easily damaged, hence the question.

    paul ron - I have a huge vinyl collection and swear by anti-static inner sleeves to store them.
    I use Nagaoka No.102 sleeves and they make a big difference to noise levels - much of the crackles and pops you hear from vinyl is not dirt but static bouncing from the surface of the record to the stylus and back.

    I may be preaching to the converted here but if not, give them a whirl...!
     
  8. paul ron

    paul ron Member

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    Not to side line this thread.... I figured the record washes are designed to lift dust out of micro grooves n work very well, so, it may help for our screens. I'm going to give it a go soon just as an experiment since I have trashed lots of screens over the years n am fed up with spending so much money on em with the crazy prices they get today.

    BTW Thanks for the sleeve advice, I may be getting all new sleves soon anyway. I've switched to non-acid all rag sleeves used by museums back in the early 70s n they helped a great deal in preserving my collection, proof is in the pudding they are still pristine. The covers on the OTOH are falling appart, crumbeling old paper. But, after not playing em in almost 40 years they tend to attract dust on their own.

    Just another tip... grounding is everything. I run a separate ground bus to every component n back to the electrical house system, as well as using a condutive foam mat on my turntable platter to keep static to a minimum, that really quiets the system. At full volume I can only hear a nice soft hissssss n no humm at all.

    Now you wouldn't know where I can score 3 heads for my Teac 3300 R-R?
     
  9. Zuikopath

    Zuikopath Member

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    Apologies for sidelining my own thread :rolleyes:

    Record cleaning can work very well - I used to work in the high-end Hi-Fi industry and we offered a cleaning service for vinyl.
    I can't remember the make of the maching now but it was a wet process type and had a marked effect on noise.
    Google 'record cleaning' for loads of web pages on the subject - try here.

    Good luck with your search for TEAC parts.
     
  10. paul ron

    paul ron Member

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    Someting just dawned on me last night, Plastic. It's immune to acid. So to burn the dirt out, why not a dunk in acid, a good rinse in fresh water n the screen should be dirt free good as new?
     
  11. epatsellis

    epatsellis Member

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    A VPI record cleaning machine, or a suitable homebuilt clone, can do wonders for vinyl you swear was junk.


    erie
    (who still has the same Ariston RD-11Superieur/Signet XK50 combo for nearly 25 years, most recently with a Monster Alpha 2 MC cart.)