Domed back of a violin on Solidworks

3D Design Volume Model
1

Hello

A friend is looking to model the back body of a violin to study it. We have problems modeling the back. Indeed, it is a piece with contours in the shape of a "strangled potato", with cuts that we know at regular intervals. I attach a test bit:

The realization of the surface is bumpy, here is what it looks like:

How to achieve correct straightening?

Thank you for your advice.

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2

Good evening

Try by unchecking the "optimize the surface" function, it is very often that it gives unexpected results, to say the least.

 

Good night

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3

post your sketch via an image and give the dimensions

to try to do something

For me, I will already cut the violin in the middle lengthwise

I will place a spline from one end to the other and make it coincide on the perpendicular splines

after smoothing via your guide curves

@+

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4

Hello

Like GT22, it would be nice to put the sketch in the post so that we can do some tests to help you find a solution to this problem...

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5

Not so simple, you will have to go through several smoothings: http://projetvioloncomposite.blogspot.be/2009/12/conception.html?m=1

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6

here I deliberately exaggerated the curves (splines)

I went through the surface (half back)

with the Fill Surface tool

Create the seam boundaries

and multiplying stress curves via splines

To optimize it would still be necessary to have a few more stress curves parallel to sketch 6

I'll let you do it ;-)

all the odds are a bottle ;-)

but overall it looks pretty much like a violin back

 

see attached file SW 2012

@+ if needed ;-)


dos_de_violon_michel_meunier.sldprt
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Hello 

As @max59 , moreover you have guide curves that go from right to left but there are none from front to back, you also have to channel the surface in this direction otherwise it is free that's what gives you this funny result.

may the force be with you.

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I turned to a smoothed base boss with a series of splines to make the couples. Unfortunately now Solidworks doesn't want to smooth with the outline of the violin. As soon as I select the outline as the guide curve, the smoothing disappears.

I put my file directly attached, it may be easier to see.

In any case, thank you for your help.

Michael


dessus_bis.sldprt
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impossible for me to open it, it's a future version, I'm in SW 2012

Have you opened my post file above???????????

if all your splines are in constrained via  meeting points

I don't see where there can be a problem

@+

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10

I don't think it's too bad ;-)

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@gt22 We found the new luthier from Lynkoa.

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12

@azrod

I did it quickly

We should optimize the thing with at least the good odds there it's only visual

but overall it looks pretty much like

From what I saw via the photos of Google who is our friend

@+......; -)......; -)

13

In fact the problem is that the outline is "retracted".

With a non-recessed outline:

It works, but with a recessed outline like this (blue line):

So it doesn't work. I don't know how to do it

 

14

you have to multiply the lines where it doesn't go the way you want it to

You have to start from your tip and draw x  spline lines

which will join the axis of the violin (the backbone) the whole thing must be in coubes

which follow the tracing of your snail start type tip

@+

15

Good evening

and do the opposite; give the total volume and rework with material removals and fillets. It should work just as well....

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I don't know how to add coherent splines. The part must be as close as possible to reality to make vibration studies on it.

I simplified it to the max, with the 5 half-torques and the perimeter.

But smoothing is still impossible.

I attach the file (2014 version).

Thank you


dessus_ter.sldprt
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impossible for me to recover your file and feed it

I stayed under SW 2012

so take screenshots and explain your problem

if you want to make a copy of the shape of a hyper realistic violin back

and depending on the brand, type and model

Indeed, the curves of the back are different 

and not so easy to achieve but it is possible

through surface

You have to do a lot of testing with the different tools proposed in the surface tool panel

It is possible to do it but it is a hell of a job

and it takes a lot of time

you need to multiply the spline curves

so that your surface follows these curves correctly

@+

18

Here's what I did in IGS format

 


dessus_ter.igs
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I must suck but your file is empty for me

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GT22, I think it's normal that you don't see anything!! I think it's the sketch that has been converted... ;-)

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