Day 15: Creating the soundbox…

DAY 15 – 29/2/2012 11-5pm.

There’s something therapeutic about building a guitar. There’s something relaxing about doing woodwork. A guitar is coming out of the woodwork… (excuse the pun). Almost done. And I think I will miss the process when I’m finished. The sanding, cutting, gluing, crafting, slowly moulding pieces of wood into a musical instrument. It’s good for the mind and soul, I’ve discovered. Productivity that you can see, as it unfolds in front of you. Evidence of progress. My mind empties itself of daily stresses, and I can see this instrument slowly coming together in my hands with every little grain I sand away, or piece of wood I glue, or carve, file, plane.

I can’t help but wonder what it will sound like when I’m done. But I can wait till that day. I’ve never heard of a student who has been unsatisfied with their guitar after working under the guidance of Chris Wynne. I have a great load of faith in him, and in my hands, and ears (the more I listen, the more I learn). But the fear popped into my head today, what if I don’t like the sound of my guitar when it’s done. I guess no one will ever know how their guitar will sound till they have finished. No two hand-made guitars are the same. There are so many variables. And it was interesting talking to Chris about the “warming up” of instruments. He says the sound of your new handmade guitar will change within the first hour of playing it. It will change more in the next week. In the next 6 months, you will notice a massive difference from the day it was made. There’s a period of adjustment. Some woods take longer than others. I understand. The wood shifts, and finds its most comfortable position after all this bending, gluing and strain has been placed on creating its new shape. Chris says guitars are like wine; they get better with age. So once this building part of the journey is done…it will be exciting to see my guitar’s playing journey.

Joining the sides and the back of the guitar

Glued the back onto the sides of the guitar:

This part felt like a huge milestone, to glue the back of the guitar to the sides. The soundbox is now taking shape, and it’s exciting to watch it come together

Most of the aligning was done in the previous lesson, as too were the notches into the sides where the bracing on the backboard would imbed into the side walls. It was a matter of whacking glue around the kerfed lining – which is created in the first place to create a larger gluing area to join the back to the sides (and the front to the sides) – then lining up the centre lines and clamping the bottom to the walls, making sure there are no gaps.

I left this to dry for 1 ½ hours to 2 hours.

Creating side strips: 

While waiting for the body to dry, I created 8 side strips to go around across the sides of the guitar. They help create rigidity in the sides, and decrease risk of warping and splitting of the wood. I cut and sanded a long piece of Queensland maple, which I’ve been using for most of the interior – bracing, etc.  3mm thick and about 5mm wide. I needed to make 8 pieces out of the long strip, and their sizes depended on the measurement between the kerfed lining, on both the top and bottoms on the sides.

Queensland maple is particularly easy to work with, it feels quite soft, so it didn’t take long to round the edges, and create a smooth finish.

I glued on the end bits of the strip that goes down the middle of the guitar to seal the book join of the backboard. Unfortunately for my vertically challenged self, I have to climb on furniture to see what I’m doing inside the newly created soundbox…..

Vertically challenged....

Before trimming excess edges...

Trimming backboard excess:

Once the backboard and sides had cemented together, you will notice there is excess backboard that needs to be trimmed off. This excess was left on deliberately till now to cater for some shift of shape of the sides. For the most part, the shape of my sides matched the template I traced onto the backboard. But in some areas, it was mm out. The important part will be getting the front to match the back when gluing the soundboard on.

I used a router to trim the excess. The router is fit with a bearing runs along the side of the guitar, stopping the blade from cutting off anymore than it needs to.
It’s important to peel away a few millimetres at a time, rather than just running the router along the edge and taking off the excess in one quick swing. If you attempt to take off too much wood, you run the risk of large flakes splitting off the backboard.

Routing excess edges off

There are some gaps between the sides and the back, here and there, but this won’t be a problem, as it will be sealed with decorating bindings.

I sanded the pencil marks off the back. You beauty! The sassafras is a gorgeous selection for the back. There’s a gorgeous curve in the back too, which will make a nice chamber for sound to resonate.

The guitar is taking shape….
Gluing on the side strips:

I glued the 8 side strips on, lining them up by eye with the bracing on the backboard.

If you’re wondering what those two little black clamps are for (the blue ones are holding the newly glued side strips); I broke off two pieces of kerfed lining by using too much force when clamping the guitar. It’s an easy fix, and just needs a little glue.

Sanding a flat surface for the soundboard to sit on:

The next step was to sand the sides of the guitar and the kerfed lining to create a flat surface for the soundboard to be glued too. While the back needed a slide angle to the kerfed lining, the soundboard is different. The soundboard should be flat, thus a flat surfaces is needed to glue it to.

It’s important to keep the guitar symmetrical. Once the sides were flat, I then had to make sure the width of the guitar was equally proportioned, and sand more off if one side was wider than the other (this is hard to explain in 3D, but basically I had to sand more kerfed lining in some places and not in others, measuring as I went).


Realigning the soundbox:

If you remember from last session, I had to align the guitar sides in the template before I could attempt to glue the back onto the sides. Seeing as the sides were created first, they have their own shape. And this shape can fluctuate while their not in their mould maintaining their bends. It’s important aesthetically, and probably sonically, to make sure these sides are parallel and symmetrical. I had to measure 3 different widths across the back of the guitar – the widest part (I’m gonna call it the bum) (370mm), the narrowest at the waist (242mm), and the width across the chest…. (would you call it the chest?) (280), and also measure the length of the guitar (485mm). I would be required to align the sides so that those measurements would be the same if measuring the same parts on the FRONT side of the guitar.

This required a little altering. First I clamped the guitar into the template to hold it into position. This proved to be challenging, as the guitar has shifted. I had to insert 3 rods (scrap pieces of wood with masking tape on the ends, to avoid scratching the guitar) in certain positions to push out certain parts of the guitar to make the measurements even. This was a constant game of measuring, cutting a rod to size, positioning it as to push out a side, measuring, realigning.

Preparing the soundboard to be glued to the sides:

It was a little bit fiddling trying to make sure the soundboard would fit nicely onto the sides of the guitar. It involved drawing centre-lines at the end of the guitar, lining up the centre of the soundboard and clamping into its “mock up” position. This is a little awkward as there are braces in the way, which still need to be removed before the lid can fit nicely.

I then traced the cutaway shape onto the soundboard. I always wondered what was involved in cutting out the cutaway shape of the soundboard. It seemed odd to me that one would just cut it out on the bandsaw, as you would just cut right through all this intricate sound bracing which is glued to the interior side of the soundboard. But… that’s what I was told to do. Just like that… I carved through the soundboard, creating the cutaway shape.

Chris Wynne... in the looking glass....

Chris had told me to leave a 5mm “danger zone”, as you do with most cuts (it’s better to have excess than not enough). And I’m darn lucky I followed his instructions, as I bumped the soundboard on a part of the bandsaw and sawed into the soundboard. It’s gotta be one of the worst things I could do at this stage in making my guitar. But thankfully, I only sawed about 5mm into the excess, and just missed eating into the soundboard ……….

Oh the band saw. You can never be careful enough. I should not get cocky now….

Next I had to

Notches created - to embed soundboard bracing into guitar sides

carve off some of the edges of the sound braces on the soundboard, so they wouldn’t get in the way when attaching to the sides. I’m not sure why I was to get rid of these braces, yet the braces on back piece of the guitar are left, and notches are created in the side walls of the guitar to make room for the braces.

I did have to create SOME notches for some of the braces. I measured their positions and carved them out.

The soundboard is almost ready to be glued to the sides. I look forward to doing this next session!

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