Stylus Photos - High Magnification

Discussion in 'Audio Hardware' started by Koptapad, Jan 31, 2008.

  1. Koptapad

    Koptapad Active Member

    Location:
    Minnetonka, MN
    I had a used Radio Shack RX-1500 cart about 5-7 years old for examination. It's got AT logos on it. Here's a link I found to a replacement stylus for it. http://www.lpgear.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=LG&Product_Code=RSRT1500 I only had maybe 100 hours on it, probably less. I usually cleaned the stylus with alcohol/cotton swab. The stylus was not cleaned before it was stowed away and I did not clean my vinyl back then too.

    This exercise was not meant to be a cleaning technique test. I was simply curious what it looked like at high magnification but I did a cleaning test for the hell of it.

    One important note. The sample being looked at needs to be conductive in the scanning electron microscope. Unfortunately, the diamond is not electrically conductive so there is some bright "charging" on the diamond. Therefore the diamond look splotchy and uneven with bright areas. But, for the third set of photos I sputtered the stylus with a thin layer of gold to make it conductive so there is no charging on those photos. The diamond is a lot more interseting in the third set due to a very clear photo.

    First Set - Stylus as is, before cleaning.

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    Second Set - After cleaning with a piece of Magic Eraser, up and down into it about 10-15 times. No compressed air after the ME, I forgot.

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    Third Set-after coating with gold. The diamond details and topography is easier to see now.

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    Looking straight down onto the stylus from above, the leading edge is down and the trailing edge is up. So, the perspective is that the vinyl would be traveling in an upward direction in the photo.

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  2. Eric B

    Eric B Active Member

    Location:
    Baltimore,MD
    Amazing!
  3. Natt

    Natt Active Member

    Location:
    Acton, Canada
    Thanks for sharing this insight with us!

    Graeme
  4. KT88

    KT88 Forum Resident

    Great photos. Looks like ya missed a spot ;-)!
    -Bill
  5. Baron Von Talbot

    Baron Von Talbot Well-Known Member

    the diamond tip seems damaged at one side..
  6. Mike in OR

    Mike in OR Through Middle-earth...onto Heart of The Sunrise

    Location:
    Portland, Oregon
    Amazing.....truly amazing photos! :thumbsup:
  7. LeeS

    LeeS Tubes Rule

    Location:
    Atlanta
    Pretty cool. I wonder what Zerodust would do.
  8. luckyman

    luckyman New Member

    Location:
    Brick, NJ
    Unbelievable pictures!:thumbsup:
  9. gloomrider

    gloomrider Forum Resident

    Location:
    Hollywood, CA, USA
    Posts like this are the reason I look at this forum several times a day! Thanks! :righton:
  10. dbz

    dbz Bolinhead.

    Location:
    Live At Leeds (UK)
    Amazing photos. Thanks for posting. A Quick question about the diamond tip (Its years since I had a turntable-but I'm getting the bug again), is it actually cut with a flat side or is that indicative of wear? If it's wear is that only 100 hours?
    Thanks.
  11. Doctorwu

    Doctorwu Well-Known Member

  12. bonjo

    bonjo Well-Known Member

    Location:
    USA
    You have a scanning electron microscope???
  13. Koptapad

    Koptapad Active Member

    Location:
    Minnetonka, MN
    That concave-looking side (third set of photos) is the trailing part so there's no contact with the vinyl? But I don't think it's really that concave. The leading edge has a small strip in the center where it's smooth too. It kind of makes sense. There is no vinyl contact directly in front but because of sharp turns in the vinyl it will hit the front at all angles. So the front will have only a small area of untouched diamond where the back edge will have a larger untouched area.
  14. KT88

    KT88 Forum Resident

    That is how a diamond is polished to shape. The photos are of an elliptical stylus. Diamonds are polished using wheels of diamond dust or similarly hard materials. not much else will put a dent in it ;-). I think that much more is made of stylus wear than actually exists. Most cartridge problems are of another mechanical source such as suspension "droop" or failure, stylus falling out of the cantilever, electrical circuit problems due to wiring failure or corrosion with age, and the ever popular cantilever being bent or broken.

    Record surfaces not being cleaned properly before play is what causes most record wear. Also it is hard to see if you have cleaned a stylus or to tell when it needs to be cleaned again visually (most of us don't have high res scopes or can't be bothered with removing the cartridge every few weeks to inspect them ;-). If some stubborn crap is stuck to the stylus, that gets dragged through the record groove and could cut into the walls or become embedded. There must be some heat build-up to cause problems in that case although it is of a "flash fast" nature and "heals" immediately. How well it "heals" is what would bother me. Imagine an object being partially embedded on a pass and the vinyl healing around it, sort of like a splinter in your finger. Microscopic photos of that at this resolution would be most interesting (wink, wink, nudge, nudge.. ;-).
    -Bill
  15. DrJ

    DrJ Forum Resident

    Location:
    Davis, CA, USA
    Incredibly cool...Thanks!
  16. KT88

    KT88 Forum Resident

    Wow...

    Here we go, Groove wall damage from a severely worn stylus and poorly adjusted tracking weight or misaligned stylus:

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    ...and stylus tip wear on an elliptical diamond (I have a stereo scope but can't quite get these levels of res and could use a bit better scope).

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    Get the whole low-down here: http://www.micrographia.com/projec/projapps/viny/viny0300.htm

    -Bill
  17. Koptapad

    Koptapad Active Member

    Location:
    Minnetonka, MN
    Interesting link. I guess it says my stylus is now almost conical in the front due to stylus wear and when new, the front was flat like the back as seen in the OM-30 photos.
  18. dbz

    dbz Bolinhead.

    Location:
    Live At Leeds (UK)
    Great:righton: many thanks guys-appreociate all the additional info.
  19. KT88

    KT88 Forum Resident


    No, I don't think so at all. Your photos are much higher resolution. So much so that I really want to see a record groove section or two (Por Favor? ;-). The OM30 photos he has are probably stock photos from ortofon or were not used to examine the tip (it is a new styuls after all) but were taken for illustrative purposes.

    What you are looking for in stylus wear is a fine polish on either side of the flat landings that have been initially polished into the stone by the mfr. Look closely at the 350x and 1000x photos and you will see an ever slightly smoother, glassier look to the stylus right at the tip, just on either side of the flat spots. That is where the record contact has heated and polished over and off a very tiny bit of the shape. Also notice that it is smoother there than at other locations on the stone, so a little bit of wear is a good thing and has an almost lubricating quality to it as it plays through the groove.

    The front landing polished on the stone creates a more narrow side to form the ellipse, and the back side which is more heavily polished really forms the larger part of the shape as it doesn't cut into the groove wall. If you look even closer, you can see that the surface of the two flat landings are not "exactly" parallel. It's close but they are off by almost a degree or so. Look at the 450x gold sputtered photo and notice how the ends of the landings tail off just away from 180 degrees apart. You can see that at the base of the stone. That is because these things are made by hand for the most part and that is super high magnification and shows incredibly fine tolerance. I would imagine that the diamonds are set in a jig and then moved into a polishing wheel and inspected until the desired shape is achieved. Your photos are amazingly revealing of just how complex the process is at that level, ie; you are Da Man ;-)! (I like looking at bugs under my stereo scope the most - it is awe inspiring and really presents a strong argument for a God greater than natural evolution, no matter how hard I try to avoid it :).
    -Bill
  20. Ski Bum

    Ski Bum Well-Known Member

    Location:
    Long Island, NY
    Great, great photos. Thanks for sharing. :righton:

    Now I just have to figure out a way to explain to my wife that I want a scanning electron microscope to assist with my stylus cleaning and maintenance. :sigh:
  21. Jerryb

    Jerryb Forum Resident

    Location:
    New Jersey
    Looks like the pictures from Mars!
  22. Koptapad

    Koptapad Active Member

    Location:
    Minnetonka, MN
  23. Dinsdale

    Dinsdale Dixie Fried

    Location:
    South Carolina
    Wow - after all these years, I've never seen the needle or the groove to this resolution. Thank you!
  24. hushypushy

    hushypushy Active Member

    Location:
    San Jose, CA
    Amazing photos! I haven't used a scanning electron microscope for years, but they are soooooo cool. The last time I used one, I was looking at a gold plated bee...the level of detail is quite simply stunning.
  25. xman

    xman Active Member

    Location:
    Los Angeles, CA
    I'll never look at my stylus again the same way. Miraculous!

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