Carving the Soundboard

Saturday, March 14, 2009.

This week I started on my soundboard. As you might recall, I purchase my European Spruce Top Wood from Stewart-MacDonald back in January and only now have I really been able to get to work on it. I may well have purchased a bit early, as I speculated back then, but I’m certainly glad to have it now.

It arrived as a mostly precut, book-matched pair of pieces (see my post “Arrival!” in January for pictures) that I finished cutting in half using a handsaw. Next, using my hand planer, I planed the freshly cut section of each of the two halves flat. Then, using my truing board, I dressed the mating edges of each half in preparation for gluing. Below are the results of my truing process.

I was pretty impressed with the final results from the truing process and found that holding the two pieces together up to a light, there were no gaps. Not too bad, I think.

One note - If you choose, as I did, to make the top guide of your truing board from plywood (and I guess this would hold true regardless of what wood you choose), be sure to sand down the very top edge, not so much to effect the squareness of the truing edge, but just enough to get rid of any splinters that might be there. I neglected to do this and ended up with a pretty good sized splinter in the base of my thumb. The price of getting excited, I guess.

So here is the soundboard while the glue is setting. I used my 192 gram strength hide glue for the joint and really like the results.

After letting the glue dry overnight and most of the next day, I used my trusty hand plane again and got the interior surface nice and flat. I would have preferred to use a powered planer for this, but I don’t have one (yet) nor do I know anyone who does. I am really quite pleased with how flat I was able to get it, though, with the hand plane.

Next I traced the finished outline of the top onto the interior surface of the wood using my acrylic template.

MISTAKE #3 (well, really close anyway): As I began to carve, fortunately no more than just the cavity you see in this picture, I realized that I had traced the outline UPSIDE-DOWN. Had I not notice this, I would have ended up making #1 a left-handed mandolin! But because I was so early in the carving process, I was able to erase my outline (done in pencil, thankfully) and re-trace it and continue.

I decided to do all my soundboard carving using hand tools rather than trying some of the power tool methods I have read about (drill press, router, etc.). I did this mostly because I already have a pretty nice selection of woodcarving tools that I am pretty comfortable using and, well, because I don’t have most of the other types (yet). For the soundboard, I am pretty happy with this decision. It is pretty easy to do, goes pretty quickly, and I really like the feel.

As I carved and as Mr. Siminoff recommends in his book, I used my soundboard gauges regularly as I carved to make sure I didn’t go too deeply, too often.

Here are some more pictures of my carving process.



In this picture, you can see I went ahead and trimmed off most of the excess material around the edges. I did this in preparation for starting on the top side.

It may not be really clear from this photo, but I missed on my depths a bit in a couple of places (too deep mostly on the edges). I am hoping this won’t affect the overall product too much, so I am going ahead with it anyway.

Something I found rather interesting was an effect of lighting. All through my initial carving, I worked in my room under pretty normal light. Turning the part back and forth as I carved (I did not have my piece bolted to the bench) and feeling the surface with my hand as I went, I was pretty happy that the surface graduations were pretty smooth. After I got far enough along, I took my soundboard downstairs to shamelessly showoff to my wife a little. At this point it was early evening and the light at her computer where she was sitting was relatively dark so, when I turned the piece to get better lighting on it, the shadow effects from the dimmer light really showed all of the imperfections I had been unable to see before. The thing looked horrible (she ooo’d and aahh’d, anyway - she is so sweet). Now that I knew, I took it back upstairs and commenced to work some more, this time in low lighting. This worked out pretty well.

One of the things I read about in several places was that other (real) luthiers use “scrapers” to smooth the surfaces of their soundboards and backs. At first I wasn’t too sure about this but as I go closer to my desired surface heights I found that my woodcarving tools were just not right for the job and that sandpaper wasn’t doing it, either. Because I didn’t have any scrapers in my toolbox, I decided to make one myself from an old, large wallpaper trowel I hadn’t used for years. After cutting the metal blade off of the trowel handle using an angle grinder with a cut-off blade, I shaped one edge of it to rough shape with my belt sander and the finish-shaped and sharpened it with a hand-file.

Talk about a handy tool, this thing rocks. I used it not only to smooth out the obviously rough areas, but also to “plane” off larger areas that were just a bit too high. I love it. You can see it in the top right corner of the picture below.

This picture shows where I have traced an outline on the top side of the wood and an edge line around the perimeter in preparation of carving on the top. I also show the templates I will use to gauge my progress on it and my scraper.

Here is a closer look at the edge line I drew. By measurement from Siminoff’s drawing, the edge width should end up being just under 3/16” thick. To mark this on my wood, I found that my mechanical pencil, laying on the workbench, makes a mark just at 3/16” - good enough, I figure, to use for roughing the top surface.

Last night I spent about two hours rough carving on the top side. Here are my results, so far.


This picture shows how I am unintentionally “signing” my mandolin as I go. This blood is not from gouging myself with a tool, as you might expect, but from a small splinter that stabbed me in the finger while wiping away some chips from the soundboard. It was such a small stab that I didn’t even know it bled until I saw it on the wood. The wound had already quit bleeding by the time I looked. Oh well. Thankfully this blood spot will be carved off later.

Second Arrival

Friday, January 30, 2009

Yet another big day for the receiving department (me, at the front door). At about 5:00 pm, UPS dropped off the first of my two books and then at about 6:30, the Fed Ex guy delivered my order from LMI.



There’s that mandolin again, sneaking in for reference (camera hog!)


Inside the box from LMI were my 4 lengths of kerfed lining (taped nicely to a stiff backing board to prevent damage in shipment, 2 spruce end blocks, 1 ebony fretboard, and my hide glue. Though I failed to get it in the photo, the glue also came with a printed sheet of instructions telling me pretty much everything I should need to know for how to prepare, use and store it.


Here is a closer shot of the glue and blocks. The blocks nominally measure 3” x 5-1/4” x 1” thick.


And, finally, here is a close-up of the fretboard (with the Sharpie as a reference - had to shoo away the mandolin for this one).

On first inspection of the book, The Mandolin Manual - The Art, Craft and Science of the Mandolin and Mandola by John Troughton, it appears that it might be just a bit off the mark for me when building my F-style. I say this because within the first paragraph of the book is explains that “The ‘traditional’ Neapolitan instrument (the classification he earlier gave the archtop mandolin) is more difficult to construct that a flat-back and is beyond the scope of this book.” He then goes on to say that it is a good book for reference when building a bowl-back instrument. As I flip through it, though, it does seem to describe and detail a lot of how-to’s and things not to do. For an example of what not to do, on page 55, when describing how to prepare the edges of the book-matched top-wood for gluing, he writes “Do not feel tempted to use abrasive paper on a straight-edge to get the centre-join edges straight: sanding a true, straight edge is very difficult and in any event the abrasive rounds off the edges and tears up the grain...” and so on. Since it’s the hope of finding just this kind of information that prompted me to buy the book in the first place, I am still looking forward to reading it through. Once I do, I will post a more informed opinion here.

For now, though, I clearly need to do some more reading (especially after reading that about not sanding the joint) before I start butchering my material. So its off to the arm chair for me.

Until next time....

Arrival!

Wednesday, January 28, 2009

Woohoooo! My first package arrived in the mail today!


It turned out to be my European Spruce Top Wood and my practice side wood (the mandolin in the picture is for size reference - I just couldn’t think of a better reference). This order came from Stewart-MacDonald and it arrived unbelievably quickly. I placed my order on Saturday, they got it out their door (according to their email) on Monday, and it was received at my doorstep on Wednesday. Pretty good service, in my book.

Here is what I got.


Each of the two items came in two pieces. The Top wood is a single wedge cut board split down the middle and the practice wood is two pieces taped together (mandolin for reference again).


It never occurred to me that the two pieces of the top wood would come still joined together, but it’s pretty obvious when I think about it that this makes it impossible for anyone to question whether they are a book-matched set when they arrive this way. This picture shows both ends and where they stopped sawing at the one end. Each of the two pieces is 6” wide by 17” long and measures 3/8” thick on the thin edge and 1” thick on the thick edge.


This just shows that the practice wood arrived as two pieces taped together. They are each 4” wide by 25” long and just a horse-hair under 1/8” thick.

There really isn’t a whole lot I can do with these right now, even if I wanted to. About the only things I could do are, of course, practice bending and separate the two top pieces. If the old axiom “use it or lose it” holds true here, seems like practicing bending before I’m ready to bend the real thing would be a bit risky. Likewise, since I don’t have the hide-glue yet with which to glue together my book-matched top pieces, there is not much value in cutting them apart right now, either.

Guess I’ll go do some more surfing...