I’ve been fitting quite a few new bridges lately, and have had some that the new foot contour is extremely different from the soundboard contour . Now, I’m no luthier, and don’t pretend to be, but using some old custom woodworking and finish carpentry skills, I’ve stumbled across an initial step that makes overcoming the big variance problem, and I thought I’d share with you – for whatever it might be worth. I apologize to those of you who may already use this, or a similar technique, but thought it might be of assistance to some, and I’ve not run across it in any of my seeking. I use Post-It Notes to get a good scribe-line on the bridge foot, and it saves an awful lot of trial-and-error time. First I merely loosen all the strings enough that I can remove the old bridge and stand the new one in its place, then re-tighten the outer two courses just enough to hold the bridge fairly tight where it touches the top. I then level the bridge (front to back, and side to side) with the fretboard, with small plastic wedges under the center recess of the foot. Then - find the highest point of gap between the bridge foot and the mandolin top, and – leaving the Post-Its still stuck together in the stack, slide whatever number of them it takes to just barely slide under this high point, and tear that stack from the pad. The thickness of the stack you tear off, is the maximum thickness that must be removed from the bridge foot, so it will fit the mando top, and be level with the fretboard. Lay the stack gently on the top (it will conform to the curvature of the top), against the bridge foot, and using a fine, sharp point, carefully scribe a line all around the bridge, keeping the tool down snug against the stack of Post-Its. I use the back of the tip of a slim modeling knife. Remove the strings; rub some chalk dust into your scribe line, so it can be seen easily; remove all the wood just to the scribe line (I refer you to Fred Ford’s technique, at Frets.com, from here.), and you’re ready to sand to final fit, without dealing with all the wobble, or worrying that you’ve removed too much material. Hope somebody might find this to be useful. - Gene
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