francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 21, 2016 16:12:29 GMT
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 21, 2016 12:48:59 GMT
Francis, I'm not seeing any pictures. Should I be? I must keep Dave happy as I gleen so much from his contributions to this forum... Glue-up time! I think you should be able to make out the plywood inner caul. The knobbly bits on the outside of the former are there to wrap a bungee cord round. That's virtually all my smaller spring clamps. Francis
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 21, 2016 10:47:37 GMT
Francis, I'm not seeing any pictures. Should I be? Not yet this bit is quite boring - layers of wood covered in clamps....
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 21, 2016 9:26:05 GMT
Making up a clamping caul for the laminated sides from 5 layers of thin (circa 1/16") plywood. I've used 3 layers between the caul and the body former to approximate the side/lamination thickness and pulled the caul to shape with a mix of heavy spring and screw clamps with a standard PVA white glue between the layers.
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 21, 2016 9:19:19 GMT
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 21, 2016 9:04:13 GMT
That looks like a success all round
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 20, 2016 20:43:48 GMT
Started my Multi-scale triple O today.
Basic's:
Western Red Cedar top plate Cherry back and sides Tulipwood laminations to the sides Mahogany neck (bolt-on) Rosewood fretboard Other details to follow.
Thickness' the Cherry sides and the Tulipwood full width laminations with the intention of getting the sides laminated and fitted to the end blocks before starting the front and back plates.
One cherry side bent and linings currently cooling down in the bender. I'll look to assemble this side and laminations before bending the second side and it's laminations (second side has a cutaway).
Francis
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 20, 2016 20:28:29 GMT
Built a tamborine into the side port
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 19, 2016 20:19:47 GMT
From your sketch Rob does that mean the ball end of the string is in contact with the soundboard? (side elevation) Sketch!!! That's a preicise meticulous scale drawing that is!!!! Of course it is - silly me, just working out whether it's first or third angle projection certainly not orthographic...
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 19, 2016 12:28:03 GMT
From your sketch Rob does that mean the ball end of the string is in contact with the soundboard? (side elevation)
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 19, 2016 12:19:59 GMT
Why not save some cash and make one? The equation of the sphere is simple enough: d = R - (Sqrt/(R^2 + r^2)) where R = radius of you dish r = radius out from the centre of your disc d = depth at radius r So for a 15 foot radius dish: R = 15 x 12 = 180" (easier to work in inches than fractional feet) r = 12 (for a 24" diameter disc) Gives 0.399" for a central depth. If you step your radius' out in 0.5" steps you can set a router up to depth and radius to cut the dish. Then just sand the steps out after routing. DropBox link to spread sheet if that helps: www.dropbox.com/s/ac5piniltqszscg/Radius%20dish%20calcs.xlsx?dl=0 Spread sheet is in mm just enter then radius of the dish needed - click elsewhere on the spreadsheet and it will automatically do the sums... Francis
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 19, 2016 10:57:56 GMT
francis - Interesting, Francis. Not doubting your findings at all, but struggling to understand them! How do the strings know what the back/sides are made of? My simple brain tells me that the same string at the same length should intonate in the same way wherever it is? What am I missing here? Sorry Rob for this sidetrack! Keith Keith, (Sorry Rob), All I can say is that it's happened consistently on 6 guitars (apart from the amazique as I've only built one with that). It could also be that in using a narrow range of timbers (i.e. Maple and E I Rosewood). The next guitar will be in cherry so see what happens then... Rob, That sounds complicated, very adjustable, but complicated. Does that put the saddle (read fret wire) quite high above the soundboard? What sort of break angle are you getting with that arrangement? Francis
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 19, 2016 8:40:55 GMT
You're very brave Rob slotting the bridge for the saddle pieces so early. I now build and finish the guitar, string it up and find the intonation points for each string, then cut the saddle slots. I found that with my maple guitars I can use a single piece saddle, my rosewood guitars need a two piece and the Amazique I just finished needed a 3 piece as the intonation point would not line up well enough to put them all on even a 1/8" wide bone saddle. Coming on well
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 19, 2016 4:35:28 GMT
Looks lovely Francis - looking forward to hearing it! Keith Thanks Keith - will probably bring it along to Paul's 'do' on the 18th June.
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francis
C.O.G.
Posts: 2,405
My main instrument is: Whatever I'm building...
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Post by francis on May 18, 2016 20:05:03 GMT
Had to change the tailpiece as the slotted front allowed the string loading to bend the whole thing upwards. Replaced with an ebony block having paired holes for the strings to go through and act as guides. Francis And I bet you didn't even bat an eyelid, did you francis ?! Lovely work. Prop it up and gaze at it lovingly for a while. You deserve it. Me! of course not. Kept my cool at all times!
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