How To Measure Guitar Neck Thickness

How to utilise the Cervix Set Gauge for a neck reset, to calculate a new bridge thickness, and setting the neck for a newly built guitar.

The Neck Gear up Guess was brought to u.s. by builder and repairman Bryan Galloup. This tool aids in the planning of a neck reset, aids in determining the necessary bridge thickness for a guitar when a cervix reset is not planned, and helps calculate the bridge thickness and neck setting information for a newly built guitar.

The Cervix Set Gauge is designed for use with our #3799 Precision Straight Edge.

Neck resetting

Step 1.

Attach the punch indicator block to the finish of the straight edge, so that the height of the aluminum indicator block is aligned with the top of the straight border (come across illustration one). Tighten the two allen set screws which concur the block on the straight edge. Place the Cervix Set Guess on a good flat surface, such as a table saw or jointer table, and check the zero. Concur the straight border vertically on the surface. Tipping the straight edge to i side or the other tin give a false reading on the punch indicator. Utilise the rotating bezel to zippo the approximate. The dial indicator should exist approximately in the middle of its range. Tape this reading, and note the reading on the small punch scale likewise.

Step 2.

Before removing the cervix from the musical instrument, take a measurement of the loftier betoken of the bridge superlative relative to the neck. Identify the straight edge down the middle of the neck, on acme of the frets. (For accuracy, and to take into account the pull-up of the soundboard, this should be washed with the strings installed and the instrument tuned to pitch. Be certain the neck is as direct every bit possible; accommodate the truss rod if necessary.) Record this reading and compare it to the null reading recorded in Pace 1. This comparison is the difference (see illustration 1) between the airplane of the fret tops and the top of the span. If the guitar neck needs to exist reset, the measurement of the span should exist significantly less (.050" to .075" or more) than the zilch point. The deviation between the two readings can be used to determine how much forest to remove from the heel to become the proper neck prepare angle. If in that location is no difference, or if the top of the bridge is slightly above the plane of the fret tops, the guitar neck does non demand to be reset, and the span will have a sufficiently tall saddle as is.

Step 3.

Once you have determined the distance from the plane of the frets to the top of the bridge, you tin calculate the amount of forest you need to remove from the heel of the neck (run across illustration 2). For example, let's choose .100" equally the difference. Using the formula: x = (Diff. x B)/A, plug in the numbers to get: 10 = (.100 x 3.625)/xi.v; therefore, x = .032". "A" is the distance from the neck/torso joint to the center of the saddle slot on the bridge, and "B" is the height of the neck heel. The Neck Set Gauge apace and accurately gives y'all the number you need for a precise neck reset. Now shave .032" off the bottom of the heel, gradually removing less and less as you movement up the heel, until nix is removed where the fingerboard joins the neck. We recommend that yous be conservative and start out a picayune less than .032", fit the cervix in place, and use the Cervix Set up Judge to check your work. Aim for a cipher reading on the gauge. (To be absolutely correct, you will need to use a prop inside the guitar under the bridge to simulate the amount of soundboard pull-up that occurs when the guitar is tuned to pitch).

Making a new bridge

With the bridge removed, and prior to making a new one, you can use the Neck Prepare Guess to determine the proper thickness for the new span. This time, position the dial indicator block at the lesser of the straight edge (run into illustration three). Concur the straight edge on a apartment surface, with the attaching block besides resting on that surface. The indicator should be near nix and the dial fully rotated, budgeted the limit of its travel. Tighten the set screws in this position. Once tightened, recheck zero, and suit the bezel. Now measure downward from zero to discover the bridge thickness. Notice that the dial indicator reads backwards, and so accept this into account. Some dial faces have opposite-reading numbers (the small-scale colored ones). This measurement is a very proficient number to utilise for your bridge height, and should put the tiptop of the bridge right at the level of the fret tops. (Once again, figure soundboard pull-up. Nosotros recommend using .025" as a adept average number if yous aren't going to measure your particular guitar).

Building a new guitar

If you lot are building a new guitar, yous volition accept to practise both operations, namely set the neck, and make a bridge or fit a pre-made bridge. Setup the Neck Set Judge as you did for making a new bridge, with the indicator attachment block at the bottom of the straight edge (see illustration 3). Set the neck for the height of the bridge you are using, working as you would for a neck reset. With the neck in place, measure out downwards from zero to the top of the guitar. If the fingerboard is non yet fretted, take into account the additional peak of the frets, which is usually well-nigh .040". Compare this measurement to the height of the bridge. This volition exist the difference number to use in the formula. If this measurement is greater than the thickness of the bridge, you might take to remove forest from the top of the dovetail. Exist sure to notice if this difference is positive or negative. That will determine where to remove wood to become a good neck set. Remember to always align the direct edge with the centerline of the guitar'due south fingerboard.

Once the cervix is fix, work on the span. If y'all are making the bridge, proceed as described in "Making a new span." If you lot are using a pre-made bridge, the Cervix Set Estimate will help you determine if you should modify its thickness prior to gluing it onto the top.

Source: https://www.stewmac.com/video-and-ideas/online-resources/learn-about-guitar-bridge-and-tailpiece-installation-and-repair/neck-set-gauge-instructions/