Guitar outline analysis

[danielechiesa]

Hi,

i'm a classical guitar maker and used to use autocad quite a bit years back for other stuff. Now i'm using it to trace the outlines of the many guitars i come across.

I would like to go a step further and be able to use autocad to extrapolate the possible design ideas of the original maker, if he did use some.

For instance, some older maker used very few circles to draw the outline.

I tried to follow the shape with arcs to identify the fewest possible to make the outline, but there might be a better, quicker and more elegant way to analyse and 'reconstruct' a geometrical design.

Any ideas?

This would help me a great deal in finding other design measures and ideas used to draw the guitar shape historically...

Thanks for any suggestion,

Daniele.

[ReMark]

Can you take a digital photograph of the guitar then bring it into AutoCAD as a raster image and literally "trace" over it?

[rustysilo]

I have seen guitar building sites that sell plans including cadd dwgs. Perhaps you could try there?

 

Otherwise, as previously mentioned, taking a photo and then tracing is likely going to be your best bet.

 

I would be curious to see some of your work.

[danielechiesa]

Hi,

thank you for the replies.

I did not explain very well: i already have raster images of photographs in autocad, and that is what i trace on top of with a pline; many segments following the outline.

Now, i could just print it out and make myself a pattern of each, but my problem is different.

Now that i DO have outlines in autocad, my wish is to be able to use the program to ANALYZE them and EXTRAPOLATE a more essential and 'original' drawing method, consisting not of small straight segments, but of very few arcs.

I am able to identify empirically MORE OR LESS where some are, but as i said, there might be a more elegant and effective way to 'reconstruct' an original design intent.

I know it is way more difficult that just tracing the original and copying it, but also way more interesting.

Please keep suggestions coming, thanks,

Daniele.

[ReMark]

Analyze and extrapolate them. That seems beyond the capability of plain old vanilla AutoCAD. Artificial Intelligence comes to mind. Or morphing.

[JD Mather]

I think I would use a parametric modeler like Autodesk Inventor.

[rustysilo]

In most cases it would appear that the general body shapes of guitars are likely freehand designs as opposed to technical designs.

[danielechiesa]

In most cases it would appear that the general body shapes of guitars are likely freehand designs as opposed to technical designs.

 

Well, this is the point: some guitars outlines (classical guitars) are definitely NOT freehand drawings: body length is 3/4 of vibrating string, lower bout is 3/4 of body, the curve from the endblock to the waist is symmetrical etc. etc.

There are so many 'coincidences', and many times the same ones in different makers, that at least in some of them are probably intentional.

I am also trying to 'redraw' the curve with the parameters i spotted (the above and more), but with my limited knowledge i have to use mainly circles, arcs and a lot of trial and error, hence asking for some help...

So i would not say the guitar outline is a technical design, but at least a geometrical drawing; definitely not freehand.