And Then They Both Sighed, Side By Side

The title of this entry is a reference to the Marx Brothers, in case you were wondering where my head is.

Here begins the making of the sides. As mentioned earlier, I have maple veneer to laminate the sides with. I intend to use three layers. The veneer is 1/42" thick. That's less than a millimetre thick! It's so thin I don't need to steam it before bending it.

 I'm starting with sheets of maple that are about 30" long by 4 5/8" wide. Earlier on I mentioned I was going to make the sides 1 1/2" wide, but I've decided I want more interior volume, particularly since the top and back are relatively shallow compared to many archtops. I'm going with 2 1/4" wide sides. This will make the total depth of the guitar about 3 1/4"; deeper than I had originally dreamed it to be, but still not overly so.

I simply used a T Square as a guide and made my cuts with a new X-acto blade. You're not being stared at by an evil eye in this photo, it's just the ceiling fan light reflecting on the T Square.

OK, so now they are cut. I have enough to do three layers on each side, as well as on the cutaway and the upper bout face. This is a figured maple, with a very nice wavy sheen, which you might just make out in the pictures if you have a good monitor.




Next will come the glue up, and pressing the strips in place on the frame.

Back to the Back

I'm down to detailing the contours of the carving around the edges, particularly on the underside. I've opened up the inside scoop quite a bit, which will make more inside space for resonance. The overall thickness of the back averages about 4mm now. There is still a tad more work to do around the contours to bring the thickness down, but it's almost there.

The outside of the back is pretty much there. I've been gradually making it smoother with progressively finer sandpaper. Although it is vaulted somewhat, the back is essentially flat near the middle. This is an unusual form to carve an archtop into. Some would probably say you can't carve it that way and expect it to sound good. We'll see what happens when it's done and I get a recording of it being played.

Moving Along To Something That Will Work

An earlier entry hinted at a system I'd been considering for making the curved guitar sides. It didn't fail, really, because I didn't try it. I just decided it probably wouldn't be as dependable a system as I want. Instead, I'm going for this kinda thing, which is closer to a typical style guitar side form.

My original idea for this clamp system was to epoxy the nut to the outer surface of the cross bar, allowing for the bolt to be tightened down through the hole and against the block. I suddenly had one of those moments where you slap yourself on the forehead and say, "duh, that's not the way to do it".

 So I removed the nut from the outer surface and ...

Where did that nut go? How's that bolt supposed to stay in place?

See it? Now I don't have to spend time doing anything to fix the nut in place. When I tighten the bolt down against the block the nut will just push against the cross bar from underneath and create it's own support. It doesn't need much pressure, just enough to keep the layers of veneer in place while the glue dries. I have a similar set up for the inside curves on either side of the guitar, as well as the fiddly bits at the top end on either side of where the neck fits in place.

Not quite sure why this didn't occur to me right from the get-go. I must have been having one of those moments where I over think the process of something, not allowing for the simple answer to come into my head until I've relaxed and looked at things with a clear mind.



The actual block is the larger piece of MDF at the bottom of the image. The smaller block has a bore hole in it, and is glued to the larger block. This provides a nest for the end of the bolt, so nothing moves when I'm fixing in place. I am so looking forward to finally getting the maple veneer laminated up into the curved sides. This is gonna be fun!!

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Here's an update, as of May 19. The side bending form is done.

 Undressed. Blocks and bolts all over the place.





Most of the blocks have a piece of PVC pipe fixed to them, to allow for contours. The one at the back end (you can just see the black square peeking out there) is flat with a piece of plastic over the surface, to avoid glue sticking to it. The black curved piece at the front end is cut from another piece of PVC pipe, having a broader curve for the shape there.

Dressed. All blocks in place, bolts inserted. I just wanted to be sure all of the hardware fit in properly before I actually start with the lamination process. Don't want things in the wrong spot, or wiggling around when it comes time to make those sides.

I Got Mail

Kerfing is such a funny word. In fact, even my spell checker doesn't recognize it. I'm here googling it, just to make sure I spelled it correctly (yes, that's the kind of guy I am).

Though I am trying to make from scratch as much of the guitar as I reasonably can, there are some aspects that I realized are too time-consuming or require tools I don't have access to in order to do a decent job. This kerfing was purchased, as I simply don't have an adequate tool to create all these little cuts with such precision. They are Honduras Mahogany.

So, to those who may be following this but are not familiar with guitar building (though kerfing is used in more than just instruments), it is a strip of wood that has little cuts that allow it to be curved to match a given contour. I have seen it used to create curved portions of furniture and occasionally in architecture. It's also a technique I have used to create sculptural works using materials like foamcore. In the case of guitar building, it is used to strengthen and increase bonding area around the edges of the body. It gets glued inside, flush with the top and bottom of the sides, allowing for a secure bond with the back and top.

Because of all the cuts it bends very easily, but I have to remember its delicate. Quit fiddling with it, I tells meself.

There are ten strips, each of them 18" X 5/8" X 3/16". I should only need eight of them to finish the guitar, but the extra two will be appreciate if I make a mistake somewhere.

When the mail delivery lady knocked on my door, I was pleased to see the poster tube. This kept the kerfing safe for the journey. If you ever have such things mailed to you, or have to mail something like it, I recommend making sure it's in a tube.

What, no clamps?

So, what's up with the straps? Let's see if my plan works. I intend to use a system to laminate up the sides that does not involve clamps. Wish me luck.

Curves

Well, I'm finally getting around to making a new form for the sides of the guitar, which will be maple laminate. This one will have plenty of room to work with and I'll be working on the outside of the curve, rather than the inside. The form is much wider than the actual guitar sides will be.

I'm using a material called Task Board to build the sides out of. This is cool stuff. It's like heavy stock cardboard, but you wet it lightly with a spray bottle and form it into curves. When it dries, it stays in the curve. It's not strong enough by itself to hold up to the pressure of forming, but I have plans to make it stronger. This is where my experience with polyurethane resin comes in to play. More on that, as I progress.

The messy looking pic with the yellow sheet at the bottom is the process of sealing the Task Board with polyurethane. This is a two part resin (1:1 mix ratio - you can only see one bottle in this pic though) that hardens within several minutes into a white plastic. Generally, I use this product for casting things from silicone molds, but for this purpose I simply spread it on the Task Board and let it saturate in. When it hardened it became a strengthening agent, as well as providing a moisture barrier to the card stock.


The surface on which the side form is glued is MDF. I used it because it is generally much more flat than other sheet products that are strong enough for the job; plywood is strong, but almost always has a bow in it. For purposes that require flatness I recommend MDF.

April 23 - The form is now complete, having the upper bout ends closed off, and ready to have the open side closed off with a second sheet of MDF (a la sandwich style). This will add more strength and provide a "trench" for the veneer and bending apparatus. It is now black because I have sanded it several times and sealed it with paint. It looks a mess, but the working surface is nice. Looking forward to starting a new post about laminating the sides with the curly maple veneer I have patiently waiting for the job.

April 26 - The open side is now closed off. Yes, that's just some heavy reading piled on top of the thing while the glue dries. I'm a low-tech kinda guy.

And with a new coat of paint make it smooth and all sealed. I went with white this time.

After I get a few other things done I 'll be starting the lamination of the sides.

The Flip Side

Well, after rather a long period of time, I finally got back into things. I recently received a new tool. It's a convex spoke shave. The rounded bottom makes carving contours ever-so-nice. And the fact that it's a well made tool means that I can actually draw the thing along the surface and expect it to cut nice little curls of wood. I've only started on the outer contour of the guitar back, but already you can see the shape I'm going for.

I'll update this post with progress pictures.

March 17 - More definition, getting closer to the desired depth at the edge.

April 23 - It looks more like this.

















April 26 - no new pictures, but the carving is still being worked on. It doesn't look much different now than it did in the April 23 entry, but the over all thickness is getting very close to my goal, which is to say 4mm. When I started, the whole laminated block weighed about four pounds. Now it weighs less than a pound.