Announcement

Collapse
No announcement yet.

Let's design our own neck jig!

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Let's design our own neck jig!

    The Dan Erlewine Neck Jig allows you to work on a neck with the normal string tension simulated- ideal for one-shot fret leveling but at $443.50 I think I better pass on that. However I do think that we could design a neck jig for leveling frets on electric guitars that would cost less than $50.



    STEWMAC.COM - Erlewine Neck Jig

    I have had a lot of luck using a notched straightedge to visually measure the neck relief when I have the truss rod and bridge adjusted exactly how I want them to be. I then loosen the truss rod (counting the turns) so that unstrung it would have roughly the same neck relief. However I just ran into an LTD EC-256FM guitar of mine that you can loosen the truss rod all you want but without strings you can't get anywhere near the desired neck relief.

    So I was checking out the very solid 24" beam level I bought from Harbor Freight for $20 (less 20% with coupon) for refret jobs...



    24 in. Solid Aluminum Level

    ... and figured that if I clamped it to the back of the body and added some sort of jack mechanism I could push on the headstock to simulate the tension created by the strings.

    For the clamp I would use the $10 12" handscrew clamp at Harbor Freight. putting neoprene rubber on one of the jaws so as to not damage the finish. Since this is a LP-style guitar with an angled headstock I would have to shim up the beam level about 3/4" to clear the headstock. With the shim I would add a second clamp on the level to make sure it wasn't going to move at all.



    12 in. Handscrew Clamp

    As for the jacking mechanism at the headstock I was thinking of cutting a C-clamp to remove the threaded piece with the swivel head and threading a hole in the level for it to go through.

    To use the MEF neck jig I would clamp on the beam level and then turn the clamp screw until the head (w/ neoprene rubber) was flush with the surface of the headstock. I would then take a few measurements of the distance between the beam level and the neck. After removing the strings I would then adjust the C-clamp piece until those measurements were duplicated.

    After setting this up the frets could be leveled exactly as they will be once you restring the guitar. If we can duplicate the neck relief of a strung guitar the fret leveling will be extremely accurate.

    A second clamp mechanism could be added in the middle of the neck to help establish the distance between the beam level and the back of the neck.

    Any suggestions about the jacking mechanism would be appreciated! (I think that a beam level with shims and clamps will handle that end of the device.)

    Steve Ahola

    P.S. I bought the 24" beam level for doing refret jobs using Franklin liquid hide glue. After tapping in all 22 frets I put 2 radiused blocks on top of the frets*** with a neck caul under the neck. I then clamp the 24" beam level on top of the two radiused blocks to keep everything even. (I use the shorter handscrew clamps on the neck and the longer one where the body is.)

    After letting the liquid hide glue set for about 3 hours I remove the clamps, the level and the blocks and check to see how level the frets are. I use a Sharpie on top of all the frets and then run a 16" sanding block with 600 grit paper softly on top of the frets to see which ones are high. I then hammer the high frets down and reinstall the radius blocks, caul, clamps and beam level and let it set for at least 8 hours.

    By doing that the frets come out very level and secured very well to the fretboard so there is not a lot of leveling (and recrowning!) to do. It works for me....

    *** The two 8" radiused blocks will cover frets #2 to #22 so I use a small C-clamp on the first fret.

    Click image for larger version

Name:	Erlewine_Neck_Jig.jpg
Views:	1
Size:	21.3 KB
ID:	869199

    Click image for larger version

Name:	24 inch beam level.JPG
Views:	1
Size:	13.5 KB
ID:	869203

    Click image for larger version

Name:	Erlewine_Neck_Jig.jpg
Views:	1
Size:	22.2 KB
ID:	869205
    Attached Files
    Last edited by Steve A.; 01-09-2015, 08:04 AM.
    The Blue Guitar
    www.blueguitar.org
    Some recordings:
    https://soundcloud.com/sssteeve/sets...e-blue-guitar/
    .

  • #2
    Quick trick for leveling top 3 strings with fret rocker- leave the bottom strings on and tune them a little bit higher to increase the tension. That did the trick with my troublesome LTD EC-256FM!

    Steve Ahola
    The Blue Guitar
    www.blueguitar.org
    Some recordings:
    https://soundcloud.com/sssteeve/sets...e-blue-guitar/
    .

    Comment


    • #3
      But, but... I don't want the fingerboard flat when strung; I want some relief. What has worked for me (and evidently others since I learned it from others) is adjust the truss rod so that the fingerboard is perfectly flat without strings, do the fret work, restring, and then adjust the truss rod again to obtain the desired relief. This is a pretty common method, isn't it?

      So I can see the neck jig being useful if there is no adjustable truss rod, or necessary range of adjustment isn't there, but Erlewine says "I can't imagine doing fret work without a neck jig." Help me understand.

      Comment


      • #4
        Using the truss rod to "straighten" the neck does a pretty damn good job MOST of the time. But because the truss rod doesn't flex like the wood (that is, unevenly) and because it may be applying pressure differently than it will with the neck strung a neck jig will always be better and give more even and predictable results.

        The idea isn't to straighten the fret line before starting work. It's to level the neck in general, end to end with middle, so that any naturally occurring uneven anomalies the neck experiences under tension can be removed. At least that's how I see it. Obviously you can't do this with relief in the neck unless you're some kind of wizard that can bevel a perfect relief with straight tools. Those supports you see between the heel and the head aren't there to adjust anomalies out before starting the work. They're there to provide support so the neck doesn't flex while you're trying to make the top into a straight line. If you bent all the irregularity out of the neck before starting, and then un tension it, the irregularities would just reappear to some degree. That's why using the truss rod is less than ideal. It can have an influence other than the woods natural irregularities. The difference is usually mice nuts, but not always and we DO want to save every 1/1000th of an inch of action height we can
        "Take two placebos, works twice as well." Enzo

        "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

        "If you're not interested in opinions and the experience of others, why even start a thread?
        You can't just expect consent." Helmholtz

        Comment


        • #5
          Originally posted by Tony Bones View Post
          But, but... I don't want the fingerboard flat when strung; I want some relief. What has worked for me (and evidently others since I learned it from others) is adjust the truss rod so that the fingerboard is perfectly flat without strings, do the fret work, restring, and then adjust the truss rod again to obtain the desired relief. This is a pretty common method, isn't it?

          So I can see the neck jig being useful if there is no adjustable truss rod, or necessary range of adjustment isn't there, but Erlewine says "I can't imagine doing fret work without a neck jig." Help me understand.
          I agree with you completely- I was referring specifically to an LTD EC-256FM guitar on which loosening the truss rod did not make the unstrung neck level. (On a different EC-256FM I refretted it after first leveling the fretboard so that loosening the truss rod would allow an unstrung neck to be level. It seems to be a common problem on these $250 guitars made in Vietnam- out of the box they play really nice but when you try to fine-tune the setup you run across all sorts of weird shit.)

          As you said you want the fretboard to be flat when leveling the frets with, say, an 18" beam sander- it is when using a fret rocker that I would want to have normal string tension on the neck because that is how the frets will be when I am playing it. (For those people who don't know a fret rocker checks frets 3 at a time allowing you to spot level the frets as needed to eliminate fret buzz.)

          While looking for a new fret rocker (I just found out that the one I've been using isn't perfectly flat on 2 of the sides. Ouch!) I ran across a entirely different solution: raise the strings at the nut to allow you to spot level the frets as indicated by the fret rocker.



          The kit itself is not regarded very highly by professionals but I like the idea of raising the strings at the nut.

          Fret Refinishing Kit - Guitar Reviews -- Fender, Gibson and All Other Guitars

          Steve Ahola

          P.S. Check yer fret rockers! I've dropped mine a few hundred times on a slab floor with very short carpeting but never thought to check the flatness with an accurate straightedge. D'oh!

          P.P.S. I just now used a whetstone (sharpening stone) to make the edges of my fret rocker flatter (I had tried files and sandpaper glued to a very flat board last night with mixed results- better but still not good enough.) It seems like it works best to sharpen the fret rocker going in one direction at a time rather than going back and forth.

          I figured out how to raise the strings so that I can fret rock the frets that I am filing down: a blank nut. I was thinking that it wouldn't be tall enough but it sits on the fretboard and not in the nut slot. D'oh!
          Last edited by Steve A.; 01-10-2015, 11:48 PM.
          The Blue Guitar
          www.blueguitar.org
          Some recordings:
          https://soundcloud.com/sssteeve/sets...e-blue-guitar/
          .

          Comment


          • #6
            Hi Steve,

            I like your idea. I'm not gonna build it, I don't have a need for it now, but it intrigued me,like a puzzle.
            I would use two leveling beams side by side, attached with bolts and distancers so you can get that top slot for all sliding attachments.
            you can check out local scrap yard for aluminum beams, L,I profiles and square tubes to make short beams for guitar body supports.
            I would use strap locks as per original design.
            That's it for now, I'll fallow this tread with interest, good luck, Damir

            P.S.

            Just a hint : extruded aluminum tubing : http://www.dajcor.com/ or this : http://www.openbeamusa.com/

            Wow, these guys have everything to build that jig same way as StewMac. I didn't check out the prices.

            http://www.rmmc.net/8020/technical-d...echnical-data/
            Last edited by epis; 01-11-2015, 10:44 PM.

            Comment


            • #7
              Originally posted by epis View Post
              I like your idea. I'm not gonna build it, I don't have a need for it now, but it intrigued me,like a puzzle.
              Me, too! I was thinking about the T-track kits at Rockler Woodworking the other night and lo and behold they have a basic starter kit on sale. The track is 4' long and can be cut into whatever pieces I need. The track would bend under the pressures involved but it can be attached to something stronger like a hardwood 2"x2". With it being for electric guitars I still like the idea of clamping whatever might hatch onto the guitar body.



              17-Piece Universal T-Track Kit, 4 ft. - Rockler Woodworking Tools

              However raising the strings at the nut and the bridge have solved the main issue at this time: being able to do fret rocker spot leveling while the guitar is strung up. I just did a Google search and could not find anybody recommending raising the strings when using a fret rocker. Although the Thomas Ginex sets sound like junk their idea of raising the strings at the nut is priceless! I could not begin to count the number of times I have rocked frets, loosened the strings to tape them out of the way, and then strung them back up to pitch to rock the frets again only to find that I took off too little or too much- this just since last May when I embarked on this accursed journey into luthiery. ("Damn you, Stew Mac- and the horse you rode in on!" )

              Steve Ahola

              P.S. My bigger files will not fit under the strings so I made up some more mini-sanders gluing sandpaper to tongue depressors. Once I start using them it gets hard to tell what the grit is so I've used a paint pen to encode thems:
              1 line for 180
              2 lines for 240
              3 lines for 320
              4 lines for 400
              5 lines for 600
              6 lines for 1500

              P.P.S. I think the first thing many people do when working on frets or fretboards is to remove the strings to get them out of the way. I usually just loosen them and tape them to the back of the neck. That way I can test my work as I go along, realizing of course that the strings treated in such a manner can skew the tests. In any case they do serve to provide the normal tension required for many of the tests. When I am finished I put a new set of strings on just to make sure that additional fine-tuning is not required- and boy do they sound good!
              Last edited by Steve A.; 01-13-2015, 12:24 AM.
              The Blue Guitar
              www.blueguitar.org
              Some recordings:
              https://soundcloud.com/sssteeve/sets...e-blue-guitar/
              .

              Comment

              Working...
              X