Tuesday, September 28, 2004


Day 3A - The Movie

I just realized that I was also taking 15 second quicktime videos in addition to still photos during the class. There was an important step we did on day 3 not shown in my last post because I had no still shots of it. I captured some frames from the video to show how we cut and glued the scarf joint for the headstock. The headstock is the angled-back part of the guitar where the tuners go.

So to start off, we had the mahogany neck blank, which is approximately 3-1/2 to 4" wide, about 1" thick, and about 30" long. Most big guitar factories would use a big 4" thick mahogany slab and just cut the whole neck out of that, all in one piece. We cut and glued a scarf joint (this is what I'm showing in this post), and used a stacked heel block, which I'll explain in the Day 4 post. This is more labor intensive than bandsawing it out of one big slab, but results in a stronger more stabile neck, and there's less waste.

We used a table saw jig of Harry's to cut the scarf joint, which will be at 15 degrees. The jig holds the neck blank at 15 degrees to the blade, and also holds it perpendicular to the table of the table saw. Jigs like these make table saw operations safer and easier because it allows you to firmly hold your workpiece and keep your fingers away from the blade.

Speaking of table saw safety, check out the safety device this guy invented for table saws:
If any part of your body touches the blade, it immediately applies a brake to the blade and it drops below the table, faster than you can see it. You would only be left with a small scratch. Look at the video on his site, it's crazy. Most of the time he used hot dogs for testing, but in one video he actually used his own finger.

So the next step is to turn that end piece around and glue it on the neck blank, and it will become the headstock. Harry has an easy way of lining up the joint so it can be glued together. Here he's using a spring clamp to line it up, there's no glue involved yet. He's drilling a small hole on either side of the neck blank. Later when he puts glue on it, he'll shove toothpicks into those holes and they will line everything up, no sliding around. The holes are drilled on a part that will be cut away when the neck is shaped, so you'll never see it on the final guitar.

Harry is spreading the glue with an old credit card or magnetic hotel keycard. I never throw away those plastic cards anymore, they're a great tool.

It's a little bit hard to see in the pics, but if you'll look closely you'll see the toothpicks sticking up out of the holes. Once they're in place, the part sticking out can be knocked off.

Now Harry is getting the cauls and clamps in place to get it all clamped solid so it will be a nice tight joint. Note the waxed paper to keep the neck from sticking to everything else. I'll show a clearer picture of everything being glued up when I post the Day 4 stuff.

Sunday, September 26, 2004


Guitar making class with Harry Fleishman, Day 3

I just realized that it's probably easier to see what's going on if I show a picture and then describe it, instead of the way I did it in my last post.

So here's one of the sides I bent. I clamped it into the form and marked where the centerline of the guitar body would be so I would know where to trim each end of the sides. I'm using a Japanese pull saw in this picture. These saws leave a smooth cut and are a joy to use. I'm using a straight block as a guide so my cut line does not wander.

This is the jig used to shape the mahogany tailblock where it will be glued to the tail end of the guitar, holding the two side pieces together at that end. This jig is used with the disc sander, also shown. The bottom part of the jig is shaped like the tail end of the guitar I'm making, so the tail block will be sanded to the same shape. The easiest thing to do would be to make a guitar shape that was flat at the tail block and heel block (where the neck attaches), but that typically doesn't result in a nice curvy guitar shape, so this is worth the effort.

Now I'm sanding the insides of the guitar sides (or ribs as some people call them). In particular I'm concentrating on the parts where the heel and tail blocks will be glues. But in general, it's a good idea to sand the whole inside nice and smooth so that it looks like nice when people take a peep in the soundhole. That sentence would be funnier with a typo.

Harry is demonstrating to us how to glue the tailblock to the ribs. Several clamps and clamping cauls are necessary to get even pressure while it glues. Since the outside surface we're clamping is curved, we use a special adjustable curved clamping caul. It's basically just a piece of MDF with slots cut into it so it's flexible. Another important thing to remember is to use wax paper so that the clamping cauls don't get accidentally glued to the guitar, or the guitar glued to the form.

Now I'm beginning to route the channel where the decorative rosette will be inlaid into the sitka spruce top. This is a laminate trimmer with a special circle cutting base that Harry made. It has a 1/4" pin that spins on a 1/4" hole I've drilled in the spruce top. I'll make several passes to get it to the full width.

Here is the rosette, and the channel is almost to the right width for it after I've made several passes with the trimmer.

So that's Day 3. If this sort of thing interests you and you can set aside the time and money to do a hands-on class, I highly recommend doing it. You can do lots of research in guitar making books and internet forums and websites, but there is no substitution for being right there in the shop with a master. It's like the difference between shooting a bullet and throwing it.

Thursday, September 23, 2004


Guitarmaking class with Harry Fleishman, Days 1 and 2

So in January of this year ('04), I had the good fortune to be able to take an acoustic guitar building class along with seven other fine folks in Harry Fleishman's shop in Sebastopol, CA, which is about an hour north of San Francisco, out in the middle of wine country.

The class was two weeks long, 12 days of class time. The goal of the class is to build an acoustic guitar from scratch. The first dozen or so blog entries will be about the class, and then I'll continue on with what I've done since the class ended... which isn't much so far, and mostly consists of me trying to get an upstairs bedroom converted into a shop.

This will be fairly detailed, but I'm trying not to make it overly detailed... It'll probably be really dry for those that aren't into guitars and instrument making, and too vague for those that are.

So the first day, I started with my East Indian Rosewood sides. I figured out the bookmatch ( do a search if you don't know what that is) and used a white pencil to lay out which end I wanted by the neck, and which I wanted at the tailblock. It's also helpful to note which side will be the top.

The next step was to square up the sides so they had a consistent width and were straight on the edge. I held the two side pieces stacked together in bookmatch arrangement and lined up the endgrain so it matched. The reason is that you want each side to be symmetrical so it looks nice at the tail block where they meet. I used Stewmac's brown masking tape at the ends to keep everything in position. I straightened one side on a jointer. Then I marked a line 4" from that edge so we could use this tablesaw jig to cut that side.

Harry taught us to use a Fox side bender. There's lots of info about these already, so I won't go into it. The short story is that you use lightbulbs for heat and then you bend the sides over a form.

Here's a bent side and the form that I'll use for assembly. This type of form is very easy and cheap to build, and can be re-used for other shapes.

Here's the rosewood back pieces being joined. These are two book matched pieces. The joining edge was initially straightened on the jointer, then finished off on a known flat sanding block with 80 grit on one side and 180 grit on the other. Then we used Stewmac's brown masking tape (which is useful for all kinds of stuff as you will find out, I ordered a case when I got home) to work as a clamp to pull the back pieces together. The glue is original Titebond. You can see I wrote "5pm" in white pencil on the back piece, this is so I know when the glue has had enough time to dry... You might be surprised at how quickly you forget when you did what, so it's good to keep little notes as you go.

The top pieces of sitka spruce were joined in the same way. Here is the top shown with the ouline of the body shape cut out of posterboard, and with the pre-made rosette which will be inlaid into the top around the soundhole.

So that's it for the first and second day of class. Interesting thing I learned while posting this: The word "blog" is not in the spellcheck's dictionary on blogger.com.

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