I wouldn't feel bad about it. The track is a famous song for them (especially for guitarists), but if you don't know the band, you probably don't know the song. So, I put the picture up to give the pun a little extra help. When you said Bigmouth there were two things I thought of. This song title and a bar band that plays R&B rock in NE Wisconsin.
I'm having trouble adding pictures here but I did my first real petite bouche rosette ever. It's a prickly little job. Not as bad as I thought it would be but still not easy. It came out pretty good. The next one will be better. I used up $40 worth of purfling strips on one top. I need to find a cheaper source for that. Someone suggest Gorilla Glue Non foaming clear for this and it seems to work great. Anyway pictures are here:
I haven't used it so I don't have an opinion. My understanding is that it can be great but also not great...there are different processes suppliers are using so it's not all one thing. It makes sense at some level as a way of creating pre-aged wood. But my understanding is that it can also make wood brittle and hard to work with.
I have a fairly good stock of nice Sitka and Engleman spruce and I should be good for a few years so I probably won't do more than experiment with it. I'm working on understanding what I have now. I am more interested in carbon fiber reinforcement on bracing right now, that seems to add a lot of stiffness without weight and also make guitars that are potentially longer lasting (can build them lighter without too much risk of top deflection).
This batch has my first real Selmer style rosettes. It was pretty intimidating and I really sweated it but once I figured it out it's not too bad. Each strip is really two .5mm strips next to each other. So the 12mm petite bouche rosette is actually 24 thin strips pushed into the purfling channel (at least that's how I did it). I did them on my CNC so I can slowly open the channel up a thousandth of an inch or so at a time until the bundle fits easily without any gaps. Glueing them in is a real pucker but I found a really good glue that doesn't swell the wood at all.
I'm always amazed at the craftsmanship of the old guys. Doing the rosettes with hide glue and channels probably cut by hand and materials that might not have been super consistent, it's very impressive.
Jangle_JamieScottish HighlandsNewDe Rijk, some Gitanes and quite a few others
Posts: 262
Great work Paul. I'm watching your progress with huge interest and admiration. With the carbon fibre for bracing, is that reinforced spruce with carbon strips or all carbon? I imagine that having some resonance with spruce braces greatly improves the resonance of the top as a whole. Would carbon kill that resonance/movement?
Can I also ask about finish? Many acoustic guitars have a tonne of nitrocellulose lacquer all over. Surely this doesn't help with tone and volume. I have taken this thick finish off a few gypsy guitars, back to bare wood and used shellac to refinish them. The resulting improvement in tone has been noticeable and sometimes dramatic. What finish do you use?
And if we are asking questions, what are the "Mickey Mouse ears" on the upper bouts with the peg holes. Is that just extra wood to allow for extra traction during the bending of the top process? Then I assume they get cut off after the shape is achieved?
Ask questions! I'm just a guy locked in a room talking to myself about making guitars. Questions are good...I can talk to other people :)
Re: Carbon, It's carbon strips either over the brace or over and under the brace. Basically you smush a carbon fiber strand under the brace, it kind of thins itself to nothing. You can also just put them over the brace. If you look at the first picture on this thread on page one, you can see a guitar I'm experimenting with this on (totally experimental guitar). I believe maybe Greg Smallman from Australia was one of the orginators of this idea, and Trevor Gore has written about it a lot.
I am definitely not an expert about it but the idea is adding a lot of stiffness and strength to the area without much additional weight. So ideally you're bracing a little lighter than you would be normally but ended up stiffer than where you started. I can not really talk about its effect on sound, I haven't actually completed a guitar with it yet. The experimental guitar might be entirely overbuilt, I'm not sure if it will sound good (that's why it's an experiment).
So your question is a good one. I think the question is more like: is the vibration coming from the flexibility of the brace/top combination or the weight/stiffness ratio. I'm asking this myself, I don't have an answer.
Finish wise thus far I don't spray so I've used french polish and oil finishes. I will be experimenting this year with some more modern cyancrolate finishes and some modern shellac based finishes. In general I think a thin finish is what you want. Some people (most?) like a super glossy flawless finish on an acoustic guitar and I think that sort of finish is easier to do on a production scale. The super thick finishes you're seeing I don't think are nitro, maybe polyurethane or something like that. I don't know a ton about sprayed finishes as I haven't used them yet. But sprayed nitro done by someone who knows what they are doing is one of the finest finishes you could ask for. It's pretty deadly stuff though, dangerous in a few ways.
Re: Mickey Mouse Ears
Those are locating marks for my workboards and molds. When I cnc the top those ears are part of the program on the top. Then I can put pins through them and they locate the top/rosette/soundhole in the proper position on my workboard. I also have them in my side mold so I can locate my sides against the top on my workboard.
This was the first guitar I designed in CNC and I made those ears uber gigantic to the point of ridiculousness but that CNC program is such a mess that I can't really redo it without starting from scratch, so....still got them ears. But they do actually work for what I need, I was just using them last night, I'll try to show a picture later.
Comments
I wouldn't feel bad about it. The track is a famous song for them (especially for guitarists), but if you don't know the band, you probably don't know the song. So, I put the picture up to give the pun a little extra help. When you said Bigmouth there were two things I thought of. This song title and a bar band that plays R&B rock in NE Wisconsin.
I'm having trouble adding pictures here but I did my first real petite bouche rosette ever. It's a prickly little job. Not as bad as I thought it would be but still not easy. It came out pretty good. The next one will be better. I used up $40 worth of purfling strips on one top. I need to find a cheaper source for that. Someone suggest Gorilla Glue Non foaming clear for this and it seems to work great. Anyway pictures are here:
Or on my Instagram
Instagram.com/paulmcevoyguitars
And let's not forget that notorious fine malt liquor "Mickey's Big Mouth", served in barrel bottles!
Oh wow I think that's mentioned in at least one Tom Waits song.
Ah yeah Frank's Wild Years, it hasn't aged super well.
Was just looking at the pics album this morning and wanted to ask, what do you think about torrified tops? Are you gonna go there?
I haven't used it so I don't have an opinion. My understanding is that it can be great but also not great...there are different processes suppliers are using so it's not all one thing. It makes sense at some level as a way of creating pre-aged wood. But my understanding is that it can also make wood brittle and hard to work with.
I have a fairly good stock of nice Sitka and Engleman spruce and I should be good for a few years so I probably won't do more than experiment with it. I'm working on understanding what I have now. I am more interested in carbon fiber reinforcement on bracing right now, that seems to add a lot of stiffness without weight and also make guitars that are potentially longer lasting (can build them lighter without too much risk of top deflection).
This batch has my first real Selmer style rosettes. It was pretty intimidating and I really sweated it but once I figured it out it's not too bad. Each strip is really two .5mm strips next to each other. So the 12mm petite bouche rosette is actually 24 thin strips pushed into the purfling channel (at least that's how I did it). I did them on my CNC so I can slowly open the channel up a thousandth of an inch or so at a time until the bundle fits easily without any gaps. Glueing them in is a real pucker but I found a really good glue that doesn't swell the wood at all.
I'm always amazed at the craftsmanship of the old guys. Doing the rosettes with hide glue and channels probably cut by hand and materials that might not have been super consistent, it's very impressive.
Great work Paul. I'm watching your progress with huge interest and admiration. With the carbon fibre for bracing, is that reinforced spruce with carbon strips or all carbon? I imagine that having some resonance with spruce braces greatly improves the resonance of the top as a whole. Would carbon kill that resonance/movement?
Can I also ask about finish? Many acoustic guitars have a tonne of nitrocellulose lacquer all over. Surely this doesn't help with tone and volume. I have taken this thick finish off a few gypsy guitars, back to bare wood and used shellac to refinish them. The resulting improvement in tone has been noticeable and sometimes dramatic. What finish do you use?
Cheers, Jamie
And if we are asking questions, what are the "Mickey Mouse ears" on the upper bouts with the peg holes. Is that just extra wood to allow for extra traction during the bending of the top process? Then I assume they get cut off after the shape is achieved?
Ask questions! I'm just a guy locked in a room talking to myself about making guitars. Questions are good...I can talk to other people :)
Re: Carbon, It's carbon strips either over the brace or over and under the brace. Basically you smush a carbon fiber strand under the brace, it kind of thins itself to nothing. You can also just put them over the brace. If you look at the first picture on this thread on page one, you can see a guitar I'm experimenting with this on (totally experimental guitar). I believe maybe Greg Smallman from Australia was one of the orginators of this idea, and Trevor Gore has written about it a lot.
I am definitely not an expert about it but the idea is adding a lot of stiffness and strength to the area without much additional weight. So ideally you're bracing a little lighter than you would be normally but ended up stiffer than where you started. I can not really talk about its effect on sound, I haven't actually completed a guitar with it yet. The experimental guitar might be entirely overbuilt, I'm not sure if it will sound good (that's why it's an experiment).
So your question is a good one. I think the question is more like: is the vibration coming from the flexibility of the brace/top combination or the weight/stiffness ratio. I'm asking this myself, I don't have an answer.
Finish wise thus far I don't spray so I've used french polish and oil finishes. I will be experimenting this year with some more modern cyancrolate finishes and some modern shellac based finishes. In general I think a thin finish is what you want. Some people (most?) like a super glossy flawless finish on an acoustic guitar and I think that sort of finish is easier to do on a production scale. The super thick finishes you're seeing I don't think are nitro, maybe polyurethane or something like that. I don't know a ton about sprayed finishes as I haven't used them yet. But sprayed nitro done by someone who knows what they are doing is one of the finest finishes you could ask for. It's pretty deadly stuff though, dangerous in a few ways.
Re: Mickey Mouse Ears
Those are locating marks for my workboards and molds. When I cnc the top those ears are part of the program on the top. Then I can put pins through them and they locate the top/rosette/soundhole in the proper position on my workboard. I also have them in my side mold so I can locate my sides against the top on my workboard.
This was the first guitar I designed in CNC and I made those ears uber gigantic to the point of ridiculousness but that CNC program is such a mess that I can't really redo it without starting from scratch, so....still got them ears. But they do actually work for what I need, I was just using them last night, I'll try to show a picture later.