Sanding/Finishing Poplar

Discussion in 'Finely Finished' started by newuser1, Oct 13, 2021.

  1. newuser1

    newuser1 Tele-Holic

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    I'm working on a 2-piece poplar guitar body and I'm in the final sanding stage before applying finish. I've sanded the body all the way up to 320 grit and yet I have spots that are fuzzy (don't know how better to describe this). The problem is more pronounced in the greenish parts of the wood.

    Surely 320 is more then adequate grit to apply finish to, so I was wondering how can I fix this issue?
    Should I keep sanding the problematic spots to higher grits?

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  2. Dano-caster

    Dano-caster Tele-Holic

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    I don't know poplar but my R.O. sander brings ash and mahogany down pretty smooth with 320.Are you hand sanding? Could be the paper also...
     
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  3. KokoTele

    KokoTele Doctor of Teleocity Vendor Member

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    Raise the grain by wiping with a damp cloth and letting it dry. Then apply a very thin wash coat* of your finish and let it cure. That will make the little fuzzy fibers hard enough to break off when you sand them.

    * Wash coat means that it’s thinned at least 50%
     
  4. newuser1

    newuser1 Tele-Holic

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  5. dsutton24

    dsutton24 Doctor of Teleocity Ad Free Member

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    You're up against a classic grain filler issue. Much depends on what your final finish will be.

    You don't want to go to higher grits. If you get it too slick you may have trouble getting your finish to stick. I only sand as high as 220.

    I did a poplar guitar. What I did was to apply a few layers of lacquer to seal the grain, sanded that back, then applied the finish as usual. It worked just fine.
     
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  6. dsutton24

    dsutton24 Doctor of Teleocity Ad Free Member

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  7. newuser1

    newuser1 Tele-Holic

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    Poplar has very tight grain, and in general doesn't require grain filler according to many posts on this forum. I also plan to use Duplicolor Perfect match for finishing, instead of lacquer.
     
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  8. newuser1

    newuser1 Tele-Holic

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    Yes, I do.
     
  9. jfgesquire

    jfgesquire Friend of Leo's

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    If I remember correctly, I used shellac as a pre sealer. Then a white vinyl sealer because I was spraying red lacquer, which goes well over white.

    No problems with the surface at all.

    I love shellac. As a very general rule - shellac sticks to everything and everything sticks to shellac.

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  10. dsutton24

    dsutton24 Doctor of Teleocity Ad Free Member

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    I've used poplar. It does have a tight grain, but depending on how it's sawn you can get the fuzz that you pictured. If you look closely at the fuzz it looks like end grain.

    If you're using Duplicolor I'd prime with primer / surfacer and sand it back to a smooth finish. Shellac would also be a good choice.
     
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  11. ChicknPickn

    ChicknPickn Tele-Afflicted Silver Supporter

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    I share your opinion regarding shellac. But I have to say that, having tried the Zinsser stuff once because I was impatient, I will only use shellac that I've mixed from flake myself from now on. I like mixing it thin and spraying from a Preval unit.
     
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  12. jfgesquire

    jfgesquire Friend of Leo's

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  13. ChicknPickn

    ChicknPickn Tele-Afflicted Silver Supporter

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  14. newuser1

    newuser1 Tele-Holic

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    I have a big can of Zinsser SealCoat, and I've had good experience spraying it with cheap HomeRight sprayer, so I'll try to seal it with that and sand it smooth after.
     
  15. eallen

    eallen Friend of Leo's

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    Normal on soft closed grain woods. No grain to be filled. Seal it, sand it, move on. Sealer will harden it enough to sand smooth.

    Eric
     
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  16. NoTeleBob

    NoTeleBob Friend of Leo's

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    Which Poplar is this? American "Tulip Poplar" or Asian Poplar?

    The American stuff is a hardwood. The Asian stuff is technically hard wood but is very soft, light, and open grained. Looks like mahogany grain, but dents with a fingernail like balsa.

    The American stuff can probably be sealed with something (above) and then finished.

    The Asian stuff needs serious filling unless you want it to look like open grain mahogany. I'd use a high build primer and sand it back to "just filling the grain". Then proceed as normal. That won't work if you're going for a natural finish though.
     
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  17. newuser1

    newuser1 Tele-Holic

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    This is American poplar, which is definitely close grained however it is quite soft and dents/scratches easily. I sprayed it with 3 coats of Zinsser shellac yesterday. It's very humid here and I have it drying in my shed, so it's not ready for sanding yet. Tomorrow if it has dried properly I will sand it with 320 and then will spray it with Duplicolor primer.

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    Last edited: Oct 15, 2021
  18. RichieB12834

    RichieB12834 TDPRI Member

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  19. netgear69

    netgear69 Tele-Afflicted

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    If it is just in one small certain area get a piece of maple sand it smooth and burnish that area with it... Burnish a fancy name for crushing the fibers
    works well i always use it on end grain like ash or maple
     
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