Acoustic guitar bridge

[Chris_G]

@Chris_G: if code works it's good, it code works and it's clean it's very good, if code works, it's clean and matches the bigger picture (FreeCAD) it's brilliant. According to my scale your code is at least good

If you know about any weak points, crashes and so on let us know

Here are a few :
- The UI is hard-coded. I think it should go in a separate QT Designer file.
- the tool can be activated several times --> strange behaviour
- what behaviour when finishing editing, if the face is part of a solid ? create a duplicate face ? replace the edited face with the new one ?
- editing point weights ( hitting 's' while grabbing points ) would need some love ( realtime display weight value / ability to reset to 1 )
- How to react when input face is a trimmed surface ( abort ? allow editing anyway ? )
- display point coordinate in UI and allow to enter numerical values.
- add ability to select rows and columns

A while age I saw a comment that FreeCAD is not designed to work with curvy surfaces. Now I look at the guitar bridge and that comment doesn't have a leg to stand on.

I agree with that comment for now. I watched all the videos of this site : http://www.aliasworkbench.com/ (very interesting) and I think there is still a long road to go

Chris

[Chris_G]

it should be handy ... at least for fixing broken step files!!

Hi,
Do you mean for filling gaps ?
Then I'm afraid it won't help a lot :
- many faces are ( I think ) trimmed surfaces. The Nurbs surface editor doesn't handle trimming curves.
FC doesn't yet offer the needed tools for this ( accessing the OCC Curve_on_surface : 2D curves expressed in the surface U/V coordinate system ).
I think it was a Google Summer of Code proposal : http://www.freecadweb.org/wiki/index.ph ... python_API
- snapping feature would be probably needed too
Chris

[Jee-Bee]

Hi,
Do you mean for filling gaps ?
Then I'm afraid it won't help a lot :
- many faces are ( I think ) trimmed surfaces. The Nurbs surface editor doesn't handle trimming curves.
FC doesn't yet offer the needed tools for this ( accessing the OCC Curve_on_surface : 2D curves expressed in the surface U/V coordinate system ).
I think it was a Google Summer of Code proposal : http://www.freecadweb.org/wiki/index.ph ... python_API
- snapping feature would be probably needed too
Chris

Hmm a pity but at least it is a step forward...

[microelly2]

Nice tool, I will read the details to get inspired.
Thank you for sharing this.

it should be handy ... at least for fixing broken step files!!

Hi,
Do you mean for filling gaps ?
Then I'm afraid it won't help a lot :
- many faces are ( I think ) trimmed surfaces. The Nurbs surface editor doesn't handle trimming curves.
FC doesn't yet offer the needed tools for this ( accessing the OCC Curve_on_surface : 2D curves expressed in the surface U/V coordinate system ).
I think it was a Google Summer of Code proposal : http://www.freecadweb.org/wiki/index.ph ... python_API
- snapping feature would be probably needed too
Chris

It's still a lot of work to connect trimmed surface the nice way but I think it will be possible

[Chris_G]

Bridge done !

Bridge-1.jpg (202.97 KiB) Viewed 2260 times

Bridge-2.jpg (195.83 KiB) Viewed 2260 times

The surface quality is very good.
It just needs a little bit of sanding one the edges ( aka "the fillet tool that NEVER fails" )
BTW, I also used FC to create the soundhole ( BOP cut of a cylinder on the body ) :

Soundhole.jpg (206.09 KiB) Viewed 2260 times

Chris

[microelly2]

nice to see this

[PrzemoF]

Thanks for posting the photos!

P.S. viewtopic.php?f=24&t=6430&start=30

[NormandC]

Chris, this is impressive craftsmanship.

I really like your bridge design. And I love the fingerboard inlay. The soundhole position is quite unconventional! I wonder how it sounds.

The sides look like East Indian Rosewood, but I'm unsure of the wood used for the tabletop. Is is koa?

[Jee-Bee]

It looks great!! but i'm happy that most bands i'm the sound tech for have normal guitars
far more easy to amplify

[Chris_G]

Chris, this is impressive craftsmanship.

I really like your bridge design. And I love the fingerboard inlay. The soundhole position is quite unconventional! I wonder how it sounds.

The sides look like East Indian Rosewood, but I'm unsure of the wood used for the tabletop. Is is koa?

Hi Normand,
Thanks for the kind words.

About the soundhole position, I am following the road that other luthiers are tracing in the recent years ( mainly Gérard Audirac ).
The soundhole's main role is to allow air flows between the inside and the outside of the body (pressure varaitions).
The sound is mainly generated by the top surface vibrating.
And the conventional position ( if it's just a convention, let's break it ! ) is, I think, quite a lot about weakening an area of the top that is already under heavy stress.
The back and sides are Brazilian RW, and the top is curly Koa.

It looks great!! but i'm happy that most bands i'm the sound tech for have normal guitars
far more easy to amplify

Hi Jee-Bee,
Well, you're right : no ready-to-use soundhole cover, no soundhole magnetic pickup ... but all the usual undersaddle pickups ( transducers / piezo ) can still be installed.

Chris