Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups Warmoth.com
Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups Warmoth.com
Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups Warmoth.com

Repairing hairline crack in poly finish

Discussion in 'Finely Finished' started by andrewnelles, Sep 30, 2017.

  1. Silverface

    Silverface Poster Extraordinaire Platinum Supporter

    Age:
    65
    Mar 2, 2003
    Lawndale CA
    The usual method is not "building it up" and feathering is pretty much impossible- it's drop-filling the gap (after dye is used) using thin viscosity CA and a pipette with a fraction of a mm spout. Once the gap is filled *then* the high part is gently scraped with a cabinet-scraper shaped razor blade. Most of the blade is masked with scotch tape; only about 2mm or so of the prepared blade is exposed. The tape prevents damage to the surrounding coating.

    Once the area is as level as possible - and sometimes it takes two or more passes of drop-filling/scraping - the area is polished
    (wet sanded starting with 2000 or finer if necessary, but a clean scraping job doesn't usually require any sanding).

    Scraping with an unprepared and/or unmasked razor blade almost always results in unwanted scratches and/or damage.
     

  2. Vizcaster

    Vizcaster Friend of Leo's

    Sep 15, 2007
    Glen Head, NY
    I wasn't suggesting feathering out the filler like autobody work or drywall where you put a hump that spreads out, but rather the process of leveling as a practical matter will mean you're sanding or scraping a larger area than the crack itself.

    I think we're saying the same thing - you wan to drop fill the gap, not try to build up the low side of a ridge that you can feel before the repair.
     

  3. andrewnelles

    andrewnelles Tele-Meister

    Age:
    30
    167
    Jul 11, 2003
    Chicago, IL
    Success. The crack is now nearly invisible. The light really has to hit it the right way for it to be visible.
     

    Attached Files:


  4. harold h

    harold h Tele-Afflicted

    Feb 15, 2004

    Looks great.

    How did you do the repair?
     

  5. andrewnelles

    andrewnelles Tele-Meister

    Age:
    30
    167
    Jul 11, 2003
    Chicago, IL
    Leveled the crack with razor scraping. There was a nearly microscopic gap left. Filled that with StewMac black tint CA. Scraped again, some light sanding, buffing, done.

    Not visible in the photo, there is a tiny spot on the crack where there was slight paint loss. Didn't notice until after the CA, so it's visible, but sealed under the CA. Doesn't really bug me.

    Guitar is all strung up now and plays great. Not bad for $270.
     

    Attached Files:


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