The Mechanics Matter. Replogle Reso parts are designed to meet close tolerances, with an eye toward the best fit as well as proprietary designs and quality materials.

“A good fit supports the mechanics of the resonator guitar and optimizes the sound”, says Mike Replogle, “and when the parts fit properly together, the complex resonator structure projects tone with excellent sustain and without buzzing or extraneous sounds and vibrations”.

A Glue-free Environment. Well-built parts that fit properly ensure that glue is not required (or recommended).  Replogle Saddles are designed to be snugly fit into the bridge slot by hand and without adhesive. Mike Replogle says,

“… the temptation is always to glue everything together. And usually with super-glue. Although there definitely is a time and place for glue, with reso parts it’s usually a corrective process- meaning, fixing something that doesn’t fit or that is broken. My philosophy it to build it right in the first place!  … Especially with reso-guitars, the resophonic pieces all fit together as a unit under the string pressure- cone, bridge and saddle- and they work best when they are allowed to function organically and without glue creating an arbitrary bond or sonic interference.”

Fitting the Saddle to the Biscuit Bridge

Pressure Fit. Replogle Saddles are designed to be lightly sanded and pressure-fit by hand into the bridge slot. As noted, a good, snug fit optimizes the vibrational mechanics of the resonator guitar and delivers the best sound– (glue is not required or recommended).

Adjusting the Saddle Thickness. The Replogle saddle itself is made slightly thicker than ⅛”, in order to allow for a bit of hand-sanding to create a snug pressure-fit. The saddle will Not fit in the bridge slot until the saddle is final-sanded during installation.

Sanding the Saddle. Use 80 or 120 grit sandpaper to hand-sand and thin the lower portion of the saddle where it will mount in the bridge slot. This can be done by sanding lightly by hand– a small sanding block is recommended to keep the sanded side smooth and level.

A Few Notes on Sanding…

  • It is not necessary to sand the entire side of the saddle, rather just the lower portion that will be pressure-fit into the bridge slot.
  • Sand the saddle in phases- do not attempt to sand the full thickness in just one pass.
  • Check the fit frequently. It is very important to sand a little, then check the thickness and the fit in the biscuit saddle, then sand again and check- repeating the process until the saddle will go into the bridge slot when pressed firmly, but can still be easily removed by hand.
  • The bridge slot holds the saddle in place and keeps it perpendicular- be sure to keep the saddle surfaces flat and square when sanding.
  • It is Not necessary to glue the saddle into the bridge when it is properly fit.
  • Avoid over-sanding that will make the saddle too thin and allow it to wobble in the bridge slot — this situation will result in the need for the use of glue to mount the saddle.

Mounting the Saddle. The saddle is mounted in the ⅛” slot cut in the top of the biscuit bridge. The saddle is pressed firmly by hand (do not use a hammer or mallet) into the biscuit slot, keeping the saddle perpendicular to the base of the biscuit.

Saddle Height Adjustment. The height adjustment process is done by removing wood from the bottom or the top of the saddle, depending on the style of saddle as noted below:

Blank Saddles. One-piece saddle blanks (no ebony cap & non-compensated) may be sanded from the top edge to adjust the saddle height. This is the easiest style of saddle to work on and the general process is as follows:

  1. Seat the saddle firmly in the biscuit bridge saddle slot (see, “Adjusting the Saddle Thickness” and “Mounting the Saddle” above).
  2. With the cover plate and cone placed in their proper position on the guitar, measure the distance from the peak (highest) edge of the biscuit resonator cone to the top edge of the coverplate palmrest strap (this measurement is the maximum height of the combined biscuit and saddle).
  3. Measure from the bottom of the biscuit bridge up toward the top of the saddle and mark the  maximum height measurement on the saddle with a pencil.
  4. Trim the height of the saddle by sanding or filing it down to the marked pencil line.
  5. Notch the slot positions of the strings on the top of the saddle, deep enough just to hold the string in position but not fully seated.
  6. Attach the biscuit to the resonator cone, using the small screw and washer through the bottom center-hole of the cone and screw it into the pilot hole on the bottom of the biscuit.
  7. Assemble the guitar– placing the biscuit cone with bridge & saddle in position, putting the coverplate in place, and then threading 3 screws spaced apart on the coverplate in the 12/4/8 positions to hold it in place
  8. String up the guitar, starting with the 1st and 6th strings and evenly increasing the string tension to keep the string pressure evenly spread out on the cone while tuning.
  9. Bring the guitar up to pitch, and check the string clearance – the string pressure will pull the cone down slightly, and that should be enough to allow the strings to clear the edge of the palmrest while being at their maximum possible height.
  10. If the strings are touching the palmrest, then adjust the strings lower by lowering the saddle height- repeating the steps above until the height is correct and the strings clear the palmrest.
  11. To complete the setup, the guitar will need to be disassembled, and the saddle will need to be properly slotted once the saddle height is correct before final reassembly.

 

Capped and/or Compensated Saddles. For Replogle Saddles that have an ebony cap and/or compensation, the height adjustment must be done by removing wood from the bottom of the saddle where it will mount in the bridge slot. This may be done by hand sanding, or using a sanding machine,

  1. Seat the saddle firmly in the biscuit bridge saddle slot (see, “Adjusting the Saddle Thickness” and “Mounting the Saddle” above).
  2. Measure the distance from the peak edge of the biscuit resonator cone to the top edge of the coverplate palmrest strap when both parts are placed in position on the guitar (this is “Measure A” and is the maximum height of the combined biscuit and saddle).
  3. Measure from the bottom of the biscuit bridge up to the top of the saddle (this is “Measure B”)
  4. Subtract “Measure A” from  “Measure B” – this is the amount that must be removed from the the bottom of the saddle.
  5. Mark the measurement on the saddle with a pencil.
  6. Trim the base of the saddle by sanding or filing it down to the marked pencil line
  7. When the saddle is pressed into the biscuit slot, the total height of biscuit + saddle will equal “Measure A”
  8. Notch the slot positions of the strings on the top of the saddle, deep enough just to hold the string in position but not fully seated
  9. Attach the biscuit to the resonator cone, using the small screw and washer through the bottom center-hole of the cone and into the pilot hole of the biscuit.
  10. Assemble the guitar– placing the biscuit cone in place, and the coverplate in place with 3 screws spaced on the coverplate to hold it in position.
  11. String up the guitar, starting with the 1st and 6th strings and evenly increasing the string tension to keep the string pressure evenly spread out on the cone
  12. Bring the guitar up to pitch, and check the string clearance – the string pressure will pull the cone down slightly, and that should be enough to allow the strings to clear the edge of the palmrest while being at their maximum possible height.
  13. If the strings are touching the palmrest, then adjust the strings lower by lowering the saddle height, and the repeat steps above until the height is correct and the strings clear the palmrest.
  14. To complete the setup, the saddle will need to be properly slotted once the saddle height is correct prior to final reassembly.

Truing the Bottom of the Saddle. It is very important that the bottom of the saddle is completely square and flat once the height has been adjusted. A sheet of sandpaper laid on a flat table (such as a drill press table, table saw, etc) can be used carefully for final truing up of the bottom of the saddle once the proper height adjustment has been achieved. It is recommended to use a square or sanding block to hold the saddle perpendicular when truing the saddle base.

Stewart MacDonald has a great jig for use with a belt sander, the Nut & Saddle Sander

 

Slotting the Saddle. String spacing is an individual thing, based on the player’s preference and the physical design of the reso guitar. Since there is no single standard for string spacing, Replogle Saddles are made without the string slots cut. Whether it is a blank, or a compensated saddle, the slots are left un-cut and they need to be done as part of the final setup process.

 

There are several ways to slot the saddle, and two of the most common are:

  1. Using a set of nut slotting files (recommended)
  2. Using an old set of strings

 

Nut File Method. The nut slotting file should be used if it is available. Some luthiers prefer to cut the slot slightly smaller than the string, and then using an old string to open the slot slightly for the final fit. Some luthiers like to use the file of the next size up from the string, allowing the string to move freely within the slot without any “break in” required. And finally, some luthiers use the same size file as the string gauge to get the precise fit on the initial slot cutting.  

 

In any case, the general process is to mark the desired spacing on the saddle with a pencil, then score that mark slightly with a sharp knife, and then using the nut file to create a slot that is as deep as 50% of the string diameter, so that the string is seated half inside the slot, and half sitting above the saddle.

 

Old String Method. For the person that does not have an extensive set of the required gauge nut files, using an old string can be a workable method– when done with care. It’s a simple matter of marking the string spacing with a pencil, and then making a very slight cut with a sharp knife. Then, wrap an old string of the desired gauge around the index finger of each hand, so that it can be pulled tight. Lastly, work the tight string back and forth across the cut in the saddle, opening it up gradually until the string is seated 50% — leaving the top 50% of the string above the saddle, Care must be taken with unwound strings, since it possible to cut too deep suddenly. The windings of the wrapped strings act more like a file and make the process easier, but in both cases there is a balance between cutting the proper depth with the knife and using the string to open up the width and depth of the cut.

 

Mixing it Up. Depending on the nut files that are available, it’s possible to use a combination of methods #1 and #2 to slot the saddle for the different string gauges.

 

Shaping the Saddle on the Biscuit Bridge. The Replogle Saddle is wider than the diameter biscuit bridge, to allow for wider string spacing on the saddle/bridge assembly. String spacing is based on the player’s preference and the instrument design, but usually it ranges from 2 ⅜” – 2 ½” total width, which requires the wider saddle. The biscuit diameter itself MUST match the cone mounting area of 2 ⅜” diameter, and if the strings are spaced wider than that, then the saddle will extend beyond the edges of the biscuit when it is mounted in the slot.

Saddle Shape Options. Leaving the saddle uncut and with square corners at the biscuit joint is functionally fine. For purely cosmetic reasons, the saddle is usually trimmed or shaped where it overhangs the biscuit. The overhang can be trimmed either a) on a slanted straight line, extending from the intersection of the bridge and the saddle to the outermost corned of the top of the saddle, or b) a soft curve from the biscuit to the top of the saddle. Either way, trimmed or untrimmed, the function of the saddle remains the same.

Shaping Steps. With the saddle properly positioned in the biscuit bridge slot, pencil mark the point on both sides of the saddle (left and right ends) where the saddle starts to extend beyond the biscuit. Then pencil in the line- for a straight line use a ruler, for a curved line a coin will work (25 cent piece or half dollar is usually good), or use a french curve. A belt sander is efficient for doing the shaping cut, although a medium fine flat file with the saddle held in a vise can also work.