The Jazz Guitar Chord Dictionary
Reply to Thread Bookmark Thread
Page 2 of 2 FirstFirst 12
Posts 26 to 31 of 31
  1. #26

    User Info Menu

    Quote Originally Posted by Jimmy blue note
    Want to know a secret? I LOVE synthetic fingerboards. Lucky for me I'm a luthier with my opinions based on practical considerations.
    No stigmas of tradition in that area anyway ;-)
    I've got a set of kitchen knives with a smooth, jet black, polished resin and fibre handles. I'm going to ask the company what it is exactly and try making some fretboard with it. Looks a million times better than Richlite, or as Red Bull calls it 'skate board ramps'.

  2.  

    The Jazz Guitar Chord Dictionary
     
  3. #27

    User Info Menu

    Since this guitar is a year round NM resident now, you need to have the fret ends dressed in the middle of the dry season. It sounds like the fretboard is not bound and the tang of the frets is protruding, not just the edges of the bead. Flushing them requires a careful touch.

    For this I use a jeweler's file with a flat face that narrows down to a point. I start filing down the end of the fret with the angle tilted back so it only catches the bead and then slowly angle the bottom of the stroke back in until the bottom of the tang is flush. You'll know by the sound and feel of the file when it's catching the wood on each side of the tang as well. Of course, if it is a bound fretboard and only the sharp corners of the bottom of the bead are exposed, your job is way easier.

    I follow the filing with sanding the finish on the edge of the fretboard only, with the grain and working through 400, 800, 1200, and 2000 grit papers- sanding only enough to minimize and scratches left by the file. If it's a gloss neck, a little buff with rubbing compound will shine it right up. I'm guessing your guitar is sounding more lively in that lower humidity. I know my steel strings' tone really sparkles when the RH gets into the 40s.

    Stay Well, RB

  4. #28

    User Info Menu

    The humidity is low year round, it's the winter temperatures that causes the wood to contract.

  5. #29

    User Info Menu

    Quote Originally Posted by Roy Boy
    Since this guitar is a year round NM resident now, you need to have the fret ends dressed in the middle of the dry season. It sounds like the fretboard is not bound and the tang of the frets is protruding, not just the edges of the bead. Flushing them requires a careful touch.

    For this I use a jeweler's file with a flat face that narrows down to a point. I start filing down the end of the fret with the angle tilted back so it only catches the bead and then slowly angle the bottom of the stroke back in until the bottom of the tang is flush. You'll know by the sound and feel of the file when it's catching the wood on each side of the tang as well. Of course, if it is a bound fretboard and only the sharp corners of the bottom of the bead are exposed, your job is way easier.

    I follow the filing with sanding the finish on the edge of the fretboard only, with the grain and working through 400, 800, 1200, and 2000 grit papers- sanding only enough to minimize and scratches left by the file. If it's a gloss neck, a little buff with rubbing compound will shine it right up. I'm guessing your guitar is sounding more lively in that lower humidity. I know my steel strings' tone really sparkles when the RH gets into the 40s.

    Stay Well, RB
    Thanks for the detailed information, Roy. What you are saying makes sense to me. I worked a little on the sprout but was reluctant to work the protruding tangs too much. I need to take it to an accomplished local luthier who specializes in building classical and flamenco guitars for another issue, so I think I will ask him to take a look at it. I could probably do it as I have the files, grit papers and polishing compounds but would rather play the guitar than work on it at this point.

    I actually try to keep the guitar at 45 to 50% RH but given where it was made that range is lower, so that's why I am seeing the sprout. I do know what you are talking about with the drier humidity levels and tone, though.

    Happy New Year to you and all the forum members!

  6. #30

    User Info Menu

    Quote Originally Posted by Clint 55
    The humidity is low year round, it's the winter temperatures that causes the wood to contract.
    I guess the RH is low year round relative to most other locations. RH is temperature dependent. Warmer air can hold more moisture than colder air. It's 38% RH right now in the office where I play and it's raining (as you know). I do think part of the problem is because of where it was built in the Pacific NW where the RH can be 70% and above.

  7. #31

    User Info Menu

    Relative humidity and temperature are interdependent as Bill says. For us it's mostly about indoor heating. If you heat the air the RH goes down. It's how a hair dryer works. After a shower the RH in the room is high, but the air coming out of the dryer is much lower, so it sucks the moisture out of your hair. Add to that the fact that moving air picks up moisture faster. So having a guitar near a hot air vent in winter is a very very bad idea in any climate.

    If you heat the air it becomes more 'thirsty'.

    Wood is quite stable thermally. It's far more sensitive to changes in Moisture Content. Like a sponge is.

    Further, wood movement is highest tangentially across the grain, so your fretboard moves more in width than it does in length. This is compounded if the board isn't finished. Finish won't stop moisture exchange with the air, but it slows it considerably.

    Relative Humidity is an expression of how much moisture air can hold at a given temperature. If air temperature is dropped to the point that RH approaches 100% we get rain. The air will not hold it's water.

    Moisture Content of wood for EG is expressed as a percentage as well, indicating the ratio of water to wood by weight. The average M.C. of wood in a N. American home is around 10%. That will change depending on the season. Typical range is something like 8 to 12%. Wood left outdoors will eventually stabilize around 20%.

    The structure of wood is similar to a bundle of tiny straws. The moisture in the straws is called Free Water. When wood takes on water the straws fill. Then the water is gradually absorbed by the cells that make the walls of the straws. This is called Bound Water. It takes heat or lower R.H. for bound water to be released. This is usually done in a kiln to bring the wood closer to the average M.C. of where the wood is intended to be used.

    That was fun! Final exams will be given on Jan 10th, barring Covid lockdowns of course :-)