Jason Tuinstra
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Alex, looks like you're in for a lot of work on this one. Should make it all the more rewarding 
Acoustic Guitar Build
- Thread starter Alex Reid
- Start date
Rob Keeble
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Following along with great interest.
Alex Reid
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Thicknessing and Rosette
After I take the plate out of the clamp I clean up the glue with a sharpened scraper. I then take it over to my drum sander and take it down to 3.0mm. I had a little offset on the glue joint so I had to even it up on both sides before taking it to final thickness. The final thickness on the drum sander is 3.00mm.
Out of the drum sander I used a 30cm length of jointed sanding block and hand sanded the plate with 180 and then 240 grit. Once again the spruce is soft so even this kind of sanding will add in reducing the thickness. At this point if I hold the plate between two fingers and tap it with my knuckle I can hear a resonance. I check often using this method.
Next step is to trace my shape onto the plate. I use my full plate template for this carefully lining up the center line.
I am now ready to mark my center position for the sound hole. The center point of my sound hole will be 148mm from the top of the body outline. And the sound hole will be 100mm in diameter. At this center point I drill a 8mm hole, which is the diameter of the axis I user on my Dremel router trammel.
I am now ready to route a 1.35mm trench in the top plate for the rosette.
Clamp plate down onto your work board and insert the trammel axis. (There is a 8mm hole also drilled into the work board)
Set your distance from the center and begin by taking light passes. Final depth will be 1.35mm.
The first trench done. There will be three in total.
Repeat procedure for each of the three rosettes we will install today.
After checking the fit of each apply glue and install the rosettes. Apply some clamp pressure (I used a long reach clamp and caul to get right on top of it) and let sit for a few hours before taking out of the clamps. Here we see all three rosettes installed.
Route out the center sound hole at 100mm diameter. Make sure you hold down both pieces as you get close to the final pass or you may find the center hole will rip away damaging your plate.
Cool it's taking shape.
Finally take it over to the band saw and cut away about 6mm away from your line.
For the last step in this rosette installation I use a well sharpened scraper and bring the rosette, which was installed a little proud, flush to the spruce sound board. Then sand lightly (be careful to not impregnate the spruce with black dust from the rosette) with my sanding block.
After I take the plate out of the clamp I clean up the glue with a sharpened scraper. I then take it over to my drum sander and take it down to 3.0mm. I had a little offset on the glue joint so I had to even it up on both sides before taking it to final thickness. The final thickness on the drum sander is 3.00mm.
Out of the drum sander I used a 30cm length of jointed sanding block and hand sanded the plate with 180 and then 240 grit. Once again the spruce is soft so even this kind of sanding will add in reducing the thickness. At this point if I hold the plate between two fingers and tap it with my knuckle I can hear a resonance. I check often using this method.
Next step is to trace my shape onto the plate. I use my full plate template for this carefully lining up the center line.
I am now ready to mark my center position for the sound hole. The center point of my sound hole will be 148mm from the top of the body outline. And the sound hole will be 100mm in diameter. At this center point I drill a 8mm hole, which is the diameter of the axis I user on my Dremel router trammel.
I am now ready to route a 1.35mm trench in the top plate for the rosette.
Clamp plate down onto your work board and insert the trammel axis. (There is a 8mm hole also drilled into the work board)
Set your distance from the center and begin by taking light passes. Final depth will be 1.35mm.
The first trench done. There will be three in total.
Repeat procedure for each of the three rosettes we will install today.
After checking the fit of each apply glue and install the rosettes. Apply some clamp pressure (I used a long reach clamp and caul to get right on top of it) and let sit for a few hours before taking out of the clamps. Here we see all three rosettes installed.
Route out the center sound hole at 100mm diameter. Make sure you hold down both pieces as you get close to the final pass or you may find the center hole will rip away damaging your plate.
Cool it's taking shape.
Finally take it over to the band saw and cut away about 6mm away from your line.
For the last step in this rosette installation I use a well sharpened scraper and bring the rosette, which was installed a little proud, flush to the spruce sound board. Then sand lightly (be careful to not impregnate the spruce with black dust from the rosette) with my sanding block.
Last edited:
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Man, that's gotta get your juices flowing. Already looking somewhat guitar-like.
Cynthia White
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This is so awe-inspiring Alex. I feel like while I'm learning how to read "See Spot Run" and you're explaining King Lear. 
Stuart Ablett
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I'm guessing the rosettes are something included in the kit?
Very cool Alex, thanks for taking us along for the ride!
Very cool Alex, thanks for taking us along for the ride!
Alex Reid
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Actually Stu there is no kit in this build. Kits come with all the parts pre-made and ready to be assembled. Buying a rosette does make it a little simpler though. The rosettes are available pre-made from many sources. Kind of like buying handles for the cabinet you just made.
Stuart Ablett
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Oh, I thought some of the parts came with the plans, I stand corrected!
I guess the rosette choice would change with the style and the wood you would use.
Very cool build
I guess the rosette choice would change with the style and the wood you would use.
Very cool build
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Austin Reed
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This is fascinating to watch, while I don't play my son does and I've long wanted to build a guitar for him.
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Nice job on the Rosette. Did you buy the trammel cutter just for this project?
Bob Gibson
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Rob Keeble
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Alex i would like to clear up one thing for myself. The board you using is you say 3.5mm thick. Then you glue to pieces together and had a little offset. You took this down in the flat sanding using your sander.
Just how thick is the outer piece of what i guess spruce on that boards ply?
Are you now after all the sanding down to being very close to the core? I imagine if you had a little offset on the join then you had to sand down both sides?
When you routed out the center how did you secure the piece in the middle that was eventually to come out. I have previously experienced just this issue not obviously making a guitar but removing a round piece in this way. My thought was seeing you work on a board leaves options to say bang a small panel pin or finishing nail into it and the workboard?
I like those clamps you made they certainly have a nice depth of throat handy for this application and i dont see them marring your workpiece.
Maybe someday you would do a blog on making a set of those? Just a future thought.
Just how thick is the outer piece of what i guess spruce on that boards ply?
Are you now after all the sanding down to being very close to the core? I imagine if you had a little offset on the join then you had to sand down both sides?
When you routed out the center how did you secure the piece in the middle that was eventually to come out. I have previously experienced just this issue not obviously making a guitar but removing a round piece in this way. My thought was seeing you work on a board leaves options to say bang a small panel pin or finishing nail into it and the workboard?
I like those clamps you made they certainly have a nice depth of throat handy for this application and i dont see them marring your workpiece.
Maybe someday you would do a blog on making a set of those? Just a future thought.
Toni Ciuraneta
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Alex, thanks for such a thorough post, I'm looking forward to see the rest specially all the process of making the mast and the general glue-up.
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Unless I'm mistaken, the spruce is not ply...it's solid spruce all the way through.
Also, I'd think the center pin going into the piece of wood below the spruce top would be enough to anchor the center disk when he cuts it out. (I'm interested to see if that's actually the case.)
Alex Reid
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Brent, yes I did buy this trammel especially for this project. It is made by Stew-Mac for use with a dremel.
Rob, Vaughn is correct in saying the spruce is solid, quatersawn stock. No plywood on this project.
Vaughn, you are also right in that center bit holding down the center donut in place while cutting it out. Sometimes my focus completely blinds me and I can't see what is right in front of my nose.
Rob, Vaughn is correct in saying the spruce is solid, quatersawn stock. No plywood on this project.
Vaughn, you are also right in that center bit holding down the center donut in place while cutting it out. Sometimes my focus completely blinds me and I can't see what is right in front of my nose.
Rob Keeble
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Ok now i understand the piece that confused me was the template half. Thanks
Now for another question. Bill just today posted a pic of his joint for the bottom of a tool box tray.
The joint he used was a rabbet lap joint. Whats your thoughts on using something like that for the joint of the two halves of the spuce?
I know you only have 3.5mm when you start so there aint much to overlap etc but it gets one away from the butt and the perfect jointing for a wide flat panel. Just asking, guess it might affect the sound??? since what i am refering to would make it what more ridgid i guess.
Now for another question. Bill just today posted a pic of his joint for the bottom of a tool box tray.
The joint he used was a rabbet lap joint. Whats your thoughts on using something like that for the joint of the two halves of the spuce?
I know you only have 3.5mm when you start so there aint much to overlap etc but it gets one away from the butt and the perfect jointing for a wide flat panel.
Just asking, guess it might affect the sound??? since what i am refering to would make it what more ridgid i guess.
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...The joint he used was a rabbet lap joint. Whats your thoughts on using something like that for the joint of the two halves of the spuce?...
...Just asking, guess it might affect the sound??? since what i am refering to would make it what more ridgid i guess.
I think your guess is correct. Ideally, you want the vibration of the top to be as uniform as possible. (Actually, you don't, but you control the vibration with the placement and dimensions of the bracing.) The half lap joint would affect that, I'm sure. I'm also guessing that a true one-piece spruce top would potentially be even better, although probably a lot harder to find the material for.
Alex Reid
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I think Robs idea of a half lap is good but as Vaughn pointed out you want uniformity. A half lap will reduce that. As well thickness makes it difficult. I have seen written in some books the luthier will put a slight angle on the joint achieving a matched butt joint that is obtuse on one side and acute on the other. We call that scarfing.
I don't know the details surrounding this but have an idea about the uniformity. Ideally you want acoustic uniformity side to side. The best was to achieve this is using a bookmatched piece of wood that has clear straight grain. I think bookmatching is best as it provides center-to-side equilibrium with both sides having the same quality of tone and structure whereas a single piece will have a certain degree of variance side-to-side.
I don't know the details surrounding this but have an idea about the uniformity. Ideally you want acoustic uniformity side to side. The best was to achieve this is using a bookmatched piece of wood that has clear straight grain. I think bookmatching is best as it provides center-to-side equilibrium with both sides having the same quality of tone and structure whereas a single piece will have a certain degree of variance side-to-side.
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Ah, I hadn't thought of the bookmatching aspect. Makes perfect sense, both visually and acoustically.
Alex Reid
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X-Brace Layout
In this step I will begin to layout the X-bracing. X-bracing is the most common method of bracing for a steel string acoustic guitar. It was developed by C.F. Martin between 1840 and 1845.
In the first step I take my plans and make triangular cut outs at the end point of each brace with my Japanese kiridashi knife. I then lay the plans out on the back of the top plate and mark with a pencil each triangular section.
I then take a straight steel rule and join up all the points effectively laying out the brace positions.
With the positions marked I lay out the braces just to check things out. The braces are also quatersawn spruce with straight clear grain. Here I want to also mark my position for the half lap cut I will make at the intersection of the x.
Here you can see the x-brace joined with a half lap joint. It is a fairly snug joint. It is not yet ready for gluing up though.
Again I lay out the braces to check things out with the x-brace in position.
In the next step I will show you the method I used for making the radius dish shown in the above two pictures. This is what is used for putting an arch on the top and back plates.
In this step I will begin to layout the X-bracing. X-bracing is the most common method of bracing for a steel string acoustic guitar. It was developed by C.F. Martin between 1840 and 1845.
In the first step I take my plans and make triangular cut outs at the end point of each brace with my Japanese kiridashi knife. I then lay the plans out on the back of the top plate and mark with a pencil each triangular section.
I then take a straight steel rule and join up all the points effectively laying out the brace positions.
With the positions marked I lay out the braces just to check things out. The braces are also quatersawn spruce with straight clear grain. Here I want to also mark my position for the half lap cut I will make at the intersection of the x.
Here you can see the x-brace joined with a half lap joint. It is a fairly snug joint. It is not yet ready for gluing up though.
Again I lay out the braces to check things out with the x-brace in position.
In the next step I will show you the method I used for making the radius dish shown in the above two pictures. This is what is used for putting an arch on the top and back plates.