Poly checking on a 71 LP ? pics, opinions wanted

Discussion in 'Luthier's Corner' started by judson, Feb 11, 2019.

  1. judson

    judson Senior Member

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    so this morning im playing a 71 lp project i bought a few months back and look down and see the sun is hitting it and a ton of spider checking is there but not even, more just in sections.

    the seller i bought it from said it was stripped and coated in polyurathane.. i thought poly would not crack like nitro?

    i wanted to lightly sand this sheen off and maybe give it a clear coat of laquer and leave it alone..there are parts that are already dull but others still have a sheen to it

    there are other issues that need addressing ahead of the finish but i was somewhat surpised at all the very fine checking that isnt really noticable from 4 feet away just if you look close...:dunno:

    if i sand with extra fine grit to knock the sheen off, will the checking leave? nothing on the back at all just the top looks like he put the poly on

    your thoughts are appreciated...thanks


    IMG_20190210_094117990.jpg IMG_20190210_094555524.jpg IMG_20190210_094521281.jpg
     

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  2. warprider

    warprider Senior Member

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    Dude. Leave it. It looks fantastic.
     
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  3. BPW666

    BPW666 Senior Member

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    Yeah me likey too, leave it love it.
    Ben
     
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  4. Heppe

    Heppe Senior Member

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    Yes! Looks great as it is:applause:
     
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  5. Rocco Crocco

    Rocco Crocco Senior Member

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    If he truly refinished it in poly, it wouldn't check like that.
     
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  6. stp

    stp Senior Member

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    poly does not check.
     
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  7. rockstar232007

    rockstar232007 Senior Member

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    Actually, depending on how thin it is applied, it can most definitely check.

    I've had vintage, poly-coated guitars, that looked just like that.
     
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  8. B. Howard

    B. Howard Premium Member

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    Most modern poly will craze like that when the maximum coating thickness is exceeded, so it was likely put on much too thick....

    Overs-paraying with lacquer or anything else will not make the crazing disappear and may in fact make it stand out more by turning the cracks either white or black.
     
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  9. Dilver

    Dilver Senior Member

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    lots if people pay for checking like that... be happy with it.
     
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  10. endial

    endial Senior Member

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    IF it's the case he stripped it, he my have neglected to wipe it down with lacquer thinner or acetone, leaving traces of the lacquer on the wood. Poly over light areas that still have lacquer might just do something like that.


    Edit: It DOES look really cool. So-
     
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  11. lunchbox

    lunchbox Senior Member

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    I’ve had poly chip off and separate from the body in bubbles (late ‘70’s Matsumoko Vantage VS650), but I’ve never seen it check like that. I don’t believe that is poly.
     
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  12. charlie chitlins

    charlie chitlins Senior Member

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    As it was explained to me buy a serious plastics guy, the molecules in plastic line up in long, straight chains.
    That's why some plastics, like candy wrappers, tear easily in one direction, but not the other.
    The only poly "checking" I've seen is long straight lines all going in the same direction.
    There was a custom painter I knew who did "crackle" paint jobs where the top coat would crack in all directions and reveal the bottom coat.
    I think this was done with synthetic/plastic-based paints.
    Whatever it is....as said...leave it. It looks great!
     
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  13. malcostuart

    malcostuart Senior Member

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    it's gained character ! love it. it's just what I'd like on a gold top, or any other actually. thanks for the eye candy !
     
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  14. malcostuart

    malcostuart Senior Member

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    in fact, a picture of the full body would be really appreciated, please ?
     
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  15. judson

    judson Senior Member

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    thanks for the coments,

    so if i lightly sanded and coated with laquer i was hoping thr checking would come thru more maybe??

    as you really dont see the checking from 2 or 3 feet away like in this pic

    i took the picguard off to see underneath is the second pic

    i think it was a cherryburst before from looking in the cavity, pots date late 1970

    neck binding removed and sanded thin, refret cuts my finger bad, toggle holes suck but plays great ....

    it has other issues i need to adress first as i mentioned but the checking caught my eye

    yesterday

    IMG_20190210_094430376_HDR.jpg IMG_20190210_093951561_HDR.jpg
    IMG_20180907_095216855_HDR[1].jpg IMG_20190210_094430376_HDR.jpg IMG_20190210_093951561_HDR.jpg
     
    Last edited: Feb 11, 2019
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  16. WhiteEpiLP

    WhiteEpiLP Senior Member

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    Maybe test in a pick up route or under the switch chip, put a drop of acetone on it an see if it softens the finish. If it is poly acetone wont do anything to it but if it is nitro it will soften it. Tread carefully though cause if it is nitro and you get the acetone anywhere you dont want it your gonna have a bad time.
     
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  17. judson

    judson Senior Member

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    thats a thought but maybe just a light sanding under the rings or pokerchip....

    i know what acetone can do as i use it too often really some would say :)

    its gonna take time to get all the other issues straightened out before i put any serious concern into the finish but it was something i just discovered and i bought this a few months back...yes its sort of cool...
     
  18. elephantrider

    elephantrider Senior Member

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    man, that this is sexy. wouldn't do a thing to it.
     
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  19. malcostuart

    malcostuart Senior Member

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    :slap:Thanks for the extra uploads, they only go to show just what a beutiful colour that top is ! So unique. The only alterations I'd do to that guitar is put some cream P90s replacement pups in. Maybe it's still a good guitar even if painted green or red but the top just wouldn't be the same. It's a unique colour , a one of a kind, things like that aren't manufactured. Just keep it clean and play it often. Thanks again:acoustic:
     
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  20. charlie chitlins

    charlie chitlins Senior Member

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    So...you're thinking about risky things to do to your guitar so your checking can be seen from further away.
    Is that accurate?
     
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