FINISHING THE GUITAR - 1
NOTE: The photos on this page are thumbnails. Click on the photo to see the full sized photo.
Once the tape is off the binding the finishing process begins. First I file and scrape the binding flush with the body - top, back and sides. Then the sanding process begins. Not much to say about it - tedious but essential. Here is the butt wedge area after it has been sanded.
I generally start with a coat of vinyl sealer before the filling process. This means that the wood takes on only a very minimal color from the filler because I like the look of the wood as natural as possible.
Occasionally I will stain mahogany. Here I am staining the mahogany back of one of the harp guitars. This is a water based stain, and works very well. The only problem with staining is that I must scrape the binding and purfling very carefully to remove the stain from this decorative feature. For a view of the scraping process, go here.
I have developed a new way of holding the body in the spraybooth. I made a small dovetail out of 1/2" Baltic birch, used some threaded inserts and a hangar bolt to create a handle. The advantage is that the sides of the guitar are completely unobstructed . The thumbscrew simply screws in until it hits the back of the dovetail on the body and applies pressure - this makes the handle completely solid and secure.
After the body is sanded, I begin the finishing process. I use nitrocellulose lacquer - like most current makers. I begin with a vinyl sealer - which is a good sealer and tends to minimize cold checking of the final finish. The back and sides are then filled with a dark wood filler, to fill the porous grain, and after suitable drying time, are sanded back to a clean smooth surface - I find a 220 grit sandpaper is more than sufficient. Then another coat of vinyl sealer, followed by lacquer. My regimen is four coats in one day, a week of drying time, followed by a light sanding with 220 grit fre-cut (stearated) paper. At this point I start filling any dips, voids or gaps so that the final finish will be completely smooth. This is followed by three coats of lacquer and another week or drying time. Then the guitar is sanded quite heavily, but carefully,(220 grit fre-cut again) to get a completely smooth surface. Then I apply two final coats of lacquer. This is allowed to dry for at least one month and is wet sanded with 600 grit wet or dry paper . A day or two of further resting time and sanding with 1000 or 1200 grit paper. A couple days more rest, and I buff the guitar on my Baldor buffer (see tools page). Some photos of the buffer in use can be found HERE. Plus one at the end of this page.
Here I am sanding the body. I use an air powered sander made by Dynabrade and I absolutely love this tool. It works much better than electric sanders. Note in the upper left hand corner of the photo - I am wearing a dust mask. Never forget to do this.
I recently bought a downdraft sanding table - a wonderful device that makes sanding much cleaner (and thus safer.)
There are always a few voids or other imperfections which are visible after the first sanding (or even before the sanding). These are "drop filled" with lacquer to bring them up to the level of the rest of the body. I use this small needle nosed bottle to do this.
After the finish is all on, and has had at least a week to cure, I wet sand it with 600 and 1000 grit wet or dry sandpaper. Here I am spraying water (with a bit of soap - I use either ivory or Murphy's Oil soap) . The soap helps lubricate the working surface and minimizes loading of the sandpaper.
Here I start the buffing process. If you look carefully you will see that the wheel is not deformed much - this is because I use a light touch. All the buffing is done on this lower quadrant of the wheel - anywhere else on the wheel and it might grab the guitar (or neck) and throw it. I know this through bitter experience.
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2219 East Franklin Ave.
Minneapolis, MN. 55404