leoroberts
C.O.G. 
Posts: 26,270 
My main instrument is: probably needing new strings
|
Post by leoroberts on Jun 16, 2013 15:52:39 GMT
This is looking marvellous.... Can't wait to hear it  |
|
ocarolan
Global Moderator
CURMUDGEONLY OLD GIT (leader - to join, just ask!)
Posts: 35,816
Mini-Profile Background: {"image":"","color":"c0cfe1"}
Mini-Profile Name Color: 182a3f
Mini-Profile Text Color: 733a1c
|
Post by ocarolan on Jun 16, 2013 15:53:39 GMT
Excitinger and excitinger!
Keith
|
|
davewhite
Luthier / Guitar Maker
Luthier
Aemulor et ambitiosior
Posts: 3,548
|
Post by davewhite on Jun 17, 2013 7:46:16 GMT
Phil, They are to help support the forces of the string tension on the top and stop it sinking in around the soundhole. The rim with the carbon fibre tubes under compression is a very stiff structure indeed. Is that common in mando building then Dave? Phil, I found the picture from my "research" it was on the Mandolin Cafe Forum and of an experimental mandolin made in 2009 by the Australian maker Graham McDonald:  It also has carbon fibre/wood lattice bracing on the top similar to the technique used on classical guitars by Greg Smallman. |
|
Phil Taylor
C.O.G.
Posts: 4,519
Mini-Profile Name Color: 680908
Mini-Profile Text Color: 121311
|
Post by Phil Taylor on Jun 17, 2013 9:06:08 GMT
Is that common in mando building then Dave? Phil, I found the picture from my "research" it was on the Mandolin Cafe Forum and of an experimental mandolin made in 2009 by the Australian maker Graham McDonald: It also has carbon fibre/wood lattice bracing on the top similar to the technique used on classical guitars by Greg Smallman. Ahh I see now - I had heard of Smallman. The top bracing on this looks a bit of a mess - I hope Mr McDonald cleaned it up a bit!! Cheers Phil |
|
davewhite
Luthier / Guitar Maker
Luthier
Aemulor et ambitiosior
Posts: 3,548
|
Post by davewhite on Jun 17, 2013 9:38:30 GMT
Phil,
That's the nature of epoxy and as it was an experiment he may not have bothered to. He is a top class maker though and his book on mandolin/bouzouki making a classic.
|
|
|
|
Post by scripsit on Jun 17, 2013 9:48:33 GMT
I think you'll find the blobs on the inside of the top will stay there: they're part of the technique of embedding the carbon fibre threads which run across the wooden 'bracing' in epoxy. It's similar to the process used in boat building where fibreglass or carbon fibre in epoxy provides the strength and the wood is more or less a spacing device.
The technique is used on steel string guitars, too. You could try googling Gore and Gilet's 'Contemporary Acoustic Guitar' set of books for detailed descriptions of the theory and practice of 'falcate bracing' with carbon fibre. The books are expensive but a fascinating read for anyone interested in what can be under the hood of acoustic guitars (there's a lot of stuff about traditional bracing and construction, too).
I've noticed from seeing (and hearing) on other forums that the Gore and Gilet methods seem to allow others to create good sounding and looking guitars, even relatively inexperienced luthiers, which to me is an indication that there is something in the techniques they describe.
Kym
|
|
Phil Taylor
C.O.G.
Posts: 4,519
Mini-Profile Name Color: 680908
Mini-Profile Text Color: 121311
|
Post by Phil Taylor on Jun 17, 2013 13:46:03 GMT
Phil, That's the nature of epoxy and as it was an experiment he may not have bothered to. He is a top class maker though and his book on mandolin/bouzouki making a classic. Ahh..... point taken. Phil |
|
davewhite
Luthier / Guitar Maker
Luthier
Aemulor et ambitiosior
Posts: 3,548
|
Post by davewhite on Jun 17, 2013 18:18:15 GMT
Next the A Frame braces are glued on using hot hide glue - these braces are flat and the ladder braces will be arched:   The European Spruce main ladder brace is profiled to a 10' radius, notched to fit together with the A frame braces and then is glued on the top using hot-hide glue:  The ladder brace below the soundhole is treated in the same fashion:  |
|
davewhite
Luthier / Guitar Maker
Luthier
Aemulor et ambitiosior
Posts: 3,548
|
Post by davewhite on Jun 18, 2013 14:03:43 GMT
The sides are profiled to match the top and back's curvature and the mahogany reverse-kerfed linings glued on using fish glue:   |
|
ocarolan
Global Moderator
CURMUDGEONLY OLD GIT (leader - to join, just ask!)
Posts: 35,816
Mini-Profile Background: {"image":"","color":"c0cfe1"}
Mini-Profile Name Color: 182a3f
Mini-Profile Text Color: 733a1c
|
Post by ocarolan on Jun 18, 2013 14:07:25 GMT
Quite a kerfuffle!  Keith |
|
davewhite
Luthier / Guitar Maker
Luthier
Aemulor et ambitiosior
Posts: 3,548
|
Post by davewhite on Jun 18, 2013 16:46:30 GMT
Now for a scary bit. This instrument will have a K&K pickup fitted but due to the limited access through the small soundhole I decided to glue the transducers onto the top before it is glued to the sides and so to check fit the 12mm hole for the end pin was drilled now:  Phew:  Here’s the K&K end-pin jack adjusted and test fitted – perfect:  The tailpiece will fit nicely above:  |
|
ocarolan
Global Moderator
CURMUDGEONLY OLD GIT (leader - to join, just ask!)
Posts: 35,816
Mini-Profile Background: {"image":"","color":"c0cfe1"}
Mini-Profile Name Color: 182a3f
Mini-Profile Text Color: 733a1c
|
Post by ocarolan on Jun 19, 2013 10:39:41 GMT
And, as well as making it easier to fit the transducers, it saves having to get all the little bit of wood from endpin drilling out through a small hole in a closed body.
Missed these lovely pics yesterday somehow. Nice!
Keith
|
|
davewhite
Luthier / Guitar Maker
Luthier
Aemulor et ambitiosior
Posts: 3,548
|
Post by davewhite on Jun 20, 2013 19:47:02 GMT
Then the mahogany side braces are notched into the linings and glued in using hot hide glue:  Here’s the completed rim set:  The Colombian Rosewood X brace cap is glued on using hot-hide glue:  The braces are then carved and the back “voiced” – here’s the result:  Notches are cut in the linings for the back brace ends and the back glued to the rim-set using fish glue:  |
|
Phil Taylor
C.O.G.
Posts: 4,519
Mini-Profile Name Color: 680908
Mini-Profile Text Color: 121311
|
Post by Phil Taylor on Jun 20, 2013 20:27:56 GMT
Looks sweet Dave Phil |
|
ocarolan
Global Moderator
CURMUDGEONLY OLD GIT (leader - to join, just ask!)
Posts: 35,816
Mini-Profile Background: {"image":"","color":"c0cfe1"}
Mini-Profile Name Color: 182a3f
Mini-Profile Text Color: 733a1c
|
Post by ocarolan on Jun 20, 2013 22:17:09 GMT
A lidless box! Yay!  Keith |
|
