Hard to believe we are already in week 7. I think the biggest difference is that we feel more comfortable with the tools and working with wood. Before when we had a very easy task, say cut a peice of wood to a specific dimension it was difficult for us to visualize the steps to get there and choose the right tools. Of course there are a lot of different ways to approach a single problem, we are coming up with them instead of having to constantly ask a resource.
This week was dedicated to the creation and installation of the bracing. Then "voicing" the top. This voicing takes a lot of patience and detail work. The basic theory is that if you have a stiff top the tone will not have the resonance nor the low tones available to it. By removing wood from the bracing you are allowing the top to be much more flexible, increasing resonance and projection and higher tones. This requires a good ear to hear these sounds as you are removing the wood.
Typically as you remove wood and approach the 'sweet spot', the trick is knowing when to stop since once you go beyond this point you are structurally at risk and your tone could get muddy very quickly. None of us had the experience or developed ear at this point so we were very dependent on Robbie's guidance. But going through this experience has definately increased my "library" of tones as well starting to learn what a guitar top should sound like.
This is a picture of the bacing on the back of the top being adjusted. Using a chisel we begin to remove wood being carefull to keep the same general shape. The brace Cian is working on has two humps. The first one on the inside needs to be about 2.5 inches from the X Brace it is connected to. The outside hump needs to be about 3 inches from the edge of the guitar. This positioning gives you optimal spacing for both tone and support.
This week was dedicated to the creation and installation of the bracing. Then "voicing" the top. This voicing takes a lot of patience and detail work. The basic theory is that if you have a stiff top the tone will not have the resonance nor the low tones available to it. By removing wood from the bracing you are allowing the top to be much more flexible, increasing resonance and projection and higher tones. This requires a good ear to hear these sounds as you are removing the wood.
Typically as you remove wood and approach the 'sweet spot', the trick is knowing when to stop since once you go beyond this point you are structurally at risk and your tone could get muddy very quickly. None of us had the experience or developed ear at this point so we were very dependent on Robbie's guidance. But going through this experience has definately increased my "library" of tones as well starting to learn what a guitar top should sound like.
This is a picture of the bacing on the back of the top being adjusted. Using a chisel we begin to remove wood being carefull to keep the same general shape. The brace Cian is working on has two humps. The first one on the inside needs to be about 2.5 inches from the X Brace it is connected to. The outside hump needs to be about 3 inches from the edge of the guitar. This positioning gives you optimal spacing for both tone and support.
This is a closeup of the brace being worked on. It is a slow process where you carve a little, tap the guitar, listen and begin removing more wood. Now is a good time to mention that your chisel is an important tool in this process. The ones at school were very dull. We did not really comprehend the issue until I purchased a set and sharpened them. WHAT A DIFFERENCE.
The main issue with reducing the bracing is that you are absolutely effecting the structure and support of the guitar. You must also be careful because a slip and the chisel will go through the top. This is also a good time to identify any gaps or issue with the bracing and repair if appropriate. We were pretty good to go but had to take quite a bit of wood off.
Once we were satisfied with the tone we started our sanding process. Event through no one would really ever see the bracing unless they used a mirror or took the top off, Robbie has installed a sense of pride in us. We are not simply building a guitar, we are learning a craft. As with every craft it is important to know how it will be judged. As I have heard many times before, the difference between a good guitar and a great guitar is attention to subtleties. We will always know what the inside looks so we want to have that "positive image". It took us a good hour or more to sand it. We started with 120 grit to reduce and blend some of the joints together than sanded the entire bracing and inside of the top with 240 grit. All that sanding in turn reduces the amount of wood and effects tone, so you need to be careful with that as well.
]Here's a picture of Cian taking a well deserved break. It was nice that we had two people so that we could switch off. Although once you get going you do get into a rhythm and feel for the particular brace you are working with. Since braces are quarter sawn they can be obnoxious at times, splintering or developing runs. You just need to be patient working in one direction than switching to another. All in all though it does teach you a lot about the properties of wood.
Here is a picture of the back of the top with all the carving and sanding complete. This is more or less what it will look like when it is glued on. What we should have is a strong top but flexible.
This picture show the bracing around the sound hole. Obviously when you cut a hole into the middle of the top this produces some structural weakness in a top where the strings are pulling at it with approximately 180lbs of pressure. Notice at the top we have our access hole to the truss rod when we put our neck on. Also the Indian rosewood reinforcement piece for the bridge.
Close up of the bracing now fully carved and sanded. You can see some of pencil circles which indicate where the brace should be. We taper the ends off to blend in with the top.
A last check for the tone and we are good to go. Next Thursday we will start to attach the front to the back, then route for your channel bindings and install them.
And finally we did have time for a little fun and a group picture of everyone there on Saturday.
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