Need advice on putting a radius on a fingerboard

Discussion in 'Tele Home Depot' started by Verzila, Jul 30, 2021.

  1. Verzila

    Verzila Tele-Meister

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    I'm putting a 12" radius on the fingerboard of this SG body and neck. I'm using a radius block with sandpaper, and I made a jig to ensure I'm running the block straight and parallel to the neck. I flattened the neck relief before I began, and the neck is well supported so it's not flexing.

    I noticed the sanding is going unevenly - in some areas I'm almost where I need to be, and in other areas there's still some way to go.

    Or am I going wrong somewhere? I've been trying (trying) to keep pressure even. Do I need to give more attention to the areas that are still high?

    Or is this normal? Maybe it's just like levelling frets; in some places you will get there earlier and other places will follow, but as long as they're all level by the end it's fine. Maybe the unfinished fretboard was uneven to start with anyway.

    Thanks for the advice WechatIMG24.jpeg WechatIMG25.jpeg WechatIMG26.jpeg WechatIMG27.jpeg
     
  2. stormin1155

    stormin1155 Tele-Holic

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    It's really hard to apply even pressure along the entire board. Add to that, you're working on a tapered board, so you have to compensate for that too. My only advice is to take it slow, and check for uniformity/straightness often. The last thing you want is to get done, only to discover that one corner is actually 1/16" thinner than the others.
     
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  3. pypa

    pypa Tele-Holic

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    Have you checked for level?
     
  4. pshupe

    pshupe Tele-Meister

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    How long is your block? I use an 18" aluminum sanding beam in a similar jig. I do 10 strokes one way then turn around and 10 strokes the other way. Did you have the chance to radius the board before putting it on the neck? That would've been easier to ensure the board is flat.

    Regards Peter.
     
  5. highwaycat

    highwaycat Tele-Holic

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    Re-mark and use a flat beam to test flatness, then use the radius beam.
    Maybe a short beam too to check 1st-12th frets. And how straight it is 15th-21st.
    Do some test runs with a 4” block too.
     
  6. Verzila

    Verzila Tele-Meister

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    No, Peter, sadly this is as it came. I scored a bargain semi-finished body and neck and this is just as it came out of the factory
     
  7. guitarbuilder

    guitarbuilder Telefied Ad Free Member

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    Remember that because it is tapered, the nut end edges will hit a different spot on the beam than the heel end. It's wider at one end than the other, so the contact spots are different until you get to the centerline. Just keep going. If you were radiusing a fretboard with a consistant width, then it would sand more evenly.

    Use the longest beam you can for the best results. Shorter blocks will produce more chances for inconsistencies.

    Check for flatness along the centerline with a known precision straightedge too.

    Other things I do are start out with a coarse grit and reverse the neck/fretboard after a while to try and even out my pressure. Once the radius is sanded in, than progressing up a couple more grits takes less time. I don't sand back and forth, only in one direction too.


    beam.jpg


    sawdust.jpg


    flatness.jpg




    Even with a radius jig, sometimes it takes a bit of sanding to even things out.



    s4.jpg


    s5.jpg
     
    Last edited: Jul 31, 2021
  8. tomasz

    tomasz Tele-Meister

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    definitely check level while you go. How well supported/flat is the back of the neck? Maybe you are getting some sagging and spring back from the neck while sanding?
     
  9. jvin248

    jvin248 Doctor of Teleocity

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    .

    +1 make sure the neck is well supported.

    Here's a method to speed up the process ... Once you see it, and as long as you have done hand sanding the old way first, you will think 'that just might work!'. There will be a lot of Nervous Nellie comments in this thread regarding their method in 3, 2, 1...



    .
     
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  10. Jim_in_PA

    Jim_in_PA Friend of Leo's Silver Supporter

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    A few things come to mind here...as a woodworker, it's important to remember that wood moves over time, expanding and shrinking seasonally and from moisture gain/loss. That can account for some of what you are experiencing here, given it appears this is not a new neck/fingerboard. The second thing to consider is that the original fretboard might not have been evenly shaped, either. Some of the issue may also be from wear.

    Just keep working carefully to get an even radius over the entire fretboard and remember, you will likely need to attend to the fret slots afterward to insure they are deep enough for new wire.
     
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  11. old wrench

    old wrench Friend of Leo's

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    Well . . . . that's pretty interesting, and, a damn good job of thinking outside of the box :).

    But, I don't see it turning the fret board radiusing business on it's head either ;).


    .
     
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  12. guitarbuilder

    guitarbuilder Telefied Ad Free Member

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    I'll stick with my radius jig design. It's a nice idea but I wonder how many screwed up radii you'd do before you get the hang of it. It would be better with a fixture to contain the sanding block.
     
  13. Telenator

    Telenator Doctor of Teleocity Vendor Member

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    I'm with the pshupe on this one. How long is your sanding block?

    Personally, I would have sanded the board flat before putting the radius on it.
     
  14. old wrench

    old wrench Friend of Leo's

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    From where I'm sitting, it looks like you are doing OK :).

    From here, it looks like there is a hump in the fret board that is centered between the 3rd and 4th frets, and you are gradually sanding it down along with the rest of the board.

    As long as your neck is set flat, and your radius block is true and long enough to aid you in keeping things flat, you'll get there - check your progress with a good straight-edge

    If you are using a 12" radius block - it's pretty obvious that the prior radius on the fret board was flatter than 12" - maybe 14" or 16" radius.

    When you are sure of the accuracy of the setup that you're employing, trust the feedback that the work piece is giving back to you - right now, it's saying that it's still too flat and it has a hump in it ;).

    A good accurate straight-edge is a necessary tool if you want to turn out good accurate work.

    .
     
  15. wingcommander

    wingcommander Tele-Meister

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  16. Peegoo

    Peegoo Poster Extraordinaire

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    You're doing fine. Keep using the chalk (or pencil) over the board to monitor your progress. The best way to get smooth, even results along the length of the board is to monitor the width of the flat unsanded stripe down the center of the board.

    The goal is to keep that stripe uniformly wide as you progress--and it becomes narrower as you remove material. If you see a portion that's wider, sand more there.

    [​IMG]
     
  17. GotTheSilver

    GotTheSilver Tele-Meister

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    Wow! Give me one of these and one of those Arbortech turboplane thingies, and I could destroy a guitar in seconds! :lol:
     
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