Saturday, March 23, 2002

Mandolin #1: In the White

Soon I was going to have myself a naked mandolin. There were just a few more steps before I could string her up and see how I'd done.



Getting Ready for Tuners
Okay, this time I used a backer block and everything. Nevermind the fact that I think I used it on the wrong side. I just do not have very good luck with drilling. While increasing the size of the holes for the tuning posts, I managed to let the drill bit rip the edges of a couple holes. Of course as soon as I was done drilling the last hole, I realized that I probably should have been more worried about tear out on the headstock overlay than on the back that would be covered by the tuning post plate. I think clamping the headstock face down to a block would have done the trick. In any case, I was getting pretty good at making the ebony dust Elmer's cocktail (you can order this as a "Black Fudd" in some of New York's most swanky luthiery shops) and was able to mostly cover up the problem. What I couldn't hide, the tuner bushings pretty much took care of.

Messy tuning post holes Filling tuning post cracks Installing the tuners  

Installing the Fingerboard and Fitting the Nut
To fit the nut, the headstock overlay edge was beveled to be 90 degrees to the neck face. The complete fingerboard was then glued in place so that it pinned the nut blank to the overlay edge. The fingerboard was "clamped" using the long binding rubber bands which have the added benefit of centering the fingerboard as they are wrapped around the neck. They are also thin enough to be wrapped all the way down to the fingerboard extension support. Sorry, no pictures of the rubber mummy... While the fingerboard was drying, I marked the nut and trimmed it to width using a coping saw and sandpaper. BTW, I've read over and over that you do not want to breath the dust from the bone nut. I don't what it would do to you but I keep picturing something along the lines of the scene where they open the Ark in "Raider's of the Lost Ark."

 Raiders

I set a general height for the nut by carefully laying my feeler gauges across the fingerboard. Unfortunately, I had no idea what measurement I was going for. But come on, that picture really looks like I know what I'm doing, right? It ends up that the nut height depends the height of the frets, the depth of the string slots, and even the height of the bridge to some extent. At that point, I just tried to match the height on another mandolin but left myself some room for error. I slotted the nut based on a template I created off the blueprint, although using a single size needle file and a little xacto saw blade for all string grooves probably negated any precision I had going.

Setting nut height 1

Final Setup and Adjustments
Finding it harder to work on the fingerboard now that it was attached to the neck and the neck attached to the body, I built a little neck rest by routing a groove in a 2x4 with the a sanding drum in the Dremel and and lining it with cork (left over from the clamps I built earlier). The neck rest extends from the headstock to the neck heel and supports the entire neck for fret work or just laying the mando on the work bench. Now equipped with a harder plastic hammer (not made by the Superball Corp), I was able to pay some more attention to the frets. Any frets that were not completely in their slots were pulled so the slots could be cleaned better. Its essential that the slots be completely free of super glue and gunked up ebony dust and binding cement or the frets will not seat well.

Now sure that the frets were well seated, I used a flat sanding block to level them. Then using masking tape to protect the fingerboard, I used a three-sided needle file to crown (blend away and flat area left by the leveling) and dress (taper the ends) the frets. Then a couple light passes with higher grit sand papers to smooth everything out without undoing my leveling work, and I was as happy as I was going to be.

Neck rest 2 Neck rest 3

 Fret adjustments Fret leveling Fret dressing 
 
Fitting the Bridge
Fitting the bridge on a new mandolin is the same process one would use on any mandolin (but with less chance of scratching the finish). On the testimony of members of the Co-Mando mailing list, I ordered a Steve Smith bridge which Steve was nice enough to pre-slot for me. Starting with 80 grit paper stuck to the top between the f-holes, the new bridge was slid forward and back to transfer the top contour to the bridge feet. The better the contact between the bridge feet and the top, the better the sound transfer. You can tell how close the fit is by noticing where dust is being left. Once dust is being produced along the entire bottom of the bridge, you know the fit is close. I switched through increasing grits of sandpaper finishing with 400 or so (I go finer for the final fit).
Fitting the bridge 1 Fitting the bridge 2 

Stringing it Up
I had ordered gold Schaller tuners and a gold Allen Monteleone style tailpiece from Stew Mac. Making sure top pre-drill all screw holes (yes, despite my bad luck with drills), the hardware went on easily and looked great. I couldn't wait to string her up...

With a pit in my stomach and preparing myself for the worst with mumblings about how it's been a learning experience, I opened the package of J-74's and started winding. It took a fair amount of trial and error to adjust the height and position of the bridge while the strings were going on. Each time I made the smallest change, I would need to tune everything up to pitch to try it out and of course the new strings were still stretching out. After an hour or so of tinkering while trying (unsuccessfully) to resist the urge to pick a couple melodies even while the tuning was still very questionable (not for the faint of ear), I was satisfied that it made any noise at all and that from what I could tell, it was quite loud and had a pleasant tone.

The next day, I was feeling more confident and, once I got everything tuned, started to diagnose some buzzes. I hammered in some high frets and even deepened the nut slots a little and was pleased to find that it seemed to be playing smoothly and in tune. It actually had a quite a loud chop and a sweet tone. There were still some buzzes despite the action still being too high at the nut, but I was starting to think the project was going to come out okay! I decided I would do my best to set things up with with my limited tools and experience, then proceed to finishing, and then bring it in to a pro for final setup adjustments.

In the white 1

Index of Project

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