Hello everyone.
Some time ago you showed me how to create the press of a tube, I'm back to show you the result, and asked a question about the calculation of the press of it what influences the length.
My result seems to be following the neutral fiber, and I would like it in relation to the outside how to do it??
Thank you in advance.
Kind regards.
For a develloppé it is normal and logical that this corresponds to the neutral fiber
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if you have elbows in all directions where the outside is
a tube deforms on the external and internal walls of said elbow or elbows
so the right base is neutral fiber
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Indeed, as said above, when we do the development whether it is a tube or a "rolled" part (so not done by bending with punch and die), the development corresponds to the neutral fiber and therefore to the circumference of the mean radius.
In 3D modeling, for the developed to match as closely as possible, the K factor must be at 0.5.
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That's what I thought, but I want to use this developed to make a cutting pattern.
Hence my question, even if I think it's not possible.
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makes a screen print
I can't open your file
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Hello
Everything that has been said above is correct.
However, if you want, you can set the value of k to 0 by editing the "Sheet metal" function of your construction tree.
Kind regards
For me, the neutral fiber is at 2/3 - 1/3 of the thickness and not in the middle.
Just change the K-factor to 1 to get the unfold value relative to the outer edge!
The factor k corresponds to the value of the position of the neutral fiber in the thickness of the sheet and therefore evolves between 0 and 1:
0 is the inside value the material only stretches when folding, 1 is the outside value the material only makes this compressed during folding
I had understood a bent tube with 1 or more bends
not unfold it with a straight tube
make a gabrit of a straight tube?????????
the perimeter of a circle has its formula
...................................................... that we learn in elementary school
http://fr.wikipedia.org/wiki/P%C3%A9rim%C3%A8tre
A little reminder!!!
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gt22 if you open the file of samos024 you will quickly understand that the advantage of unfolding its tube is not on the unfolded width dimension but on the parabolic shape which is generated by the inclined cut at the end of this tube ... Otherwise, without calculating anything (even by hand) you just have to measure the outer edge in solidworks (because first of all I'm super lazy and when there's a way to calculate anything, I don't bother)
I can't open its future version file
I'm under 2012 (I've already written it on the thread)
For laziness believe me you're not the only one
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ok obviously without the open room it's more difficult to understand ... Well come on, it's time to move on to the 2013 GT22 :o) !!
I'm of good composition so I'd take the reminder on the perimeter with a big smile.
For the people who managed to open the file (and knock laugh), my question is precisely about the influence of the K factor in this kind of example; I tried and it didn't change my route, that's why I posted.
It can be assigned to several places so which one to take??
Kind regards.
Samos:
in your creation tree you have a folder "Sheet metal" you unfold it with the small +, right click on the function that is in it "Sheet metal(3)" edit the function and you change the K factor here, you'll see it will work, I did it at home ;o)
Thank you fthomas, nickel.
I had found it when I received your email.
Have a good end of the day to all.
The effect may not be very visible in this case because the thickness is small compared to the perimeter. If you try with a thicker sheet metal it will be more marked.
Be careful when changing the position of the neutral fiber (which by definition is the one whose length does not move when rolling). If you want to make a paper simulation, you can take the outer length. If you make a jig to cut a thicker sheet with the outer length, you will end up with a tube with a larger diameter than expected.
As s.b remarks, it is also likely that the neutral fiber is not quite in the middle.... Good luck.
Hi samos024
Here is a tutorial video that corresponds to your request
having now understood what the latter was
so that the answers are possible by the + large number (SW version or other log)
A screen print is + easy to understand
+ here we start with a 3 D sketch
the procedure for carrying out the development of 1 tap with a drawing
http://www.youtube.com/watch?v=qZTUmYKNZGo
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another tutorial
http://www.youtube.com/watch?v=vzGlgZbUg4Q
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