2.5D tube lasercutting ; how to draw?

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chrisb
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Re: 2.5D tube lasercutting ; how to draw?

Postby chrisb » Thu Nov 15, 2018 11:55 pm

Perhaps you can find a solution based on the following thoughts:
- Search the forum on how to map a sketch to a cylinder
- Map the sketch to the inside of your tube
- map it enlarged on the outside
- make a subtractive loft.

Something like this. I did not map the faces, it's only to show the loft:
Attachments
Bildschirmfoto 2018-11-16 um 00.50.09.png
Bildschirmfoto 2018-11-16 um 00.50.09.png (41.49 KiB) Viewed 149 times
Koemi
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Re: 2.5D tube lasercutting ; how to draw?

Postby Koemi » Fri Nov 16, 2018 7:10 am

gntech wrote:
Thu Nov 15, 2018 2:58 pm
Perhaps you already know this but I want to write it just in case it will help you:

As a workaround to your problem I can inform that there are tube laser cutters nowadays that have tilting laser beam so you do not have to make the cut perpendicular to the surface of the pipe to be able to manufacture it.
Yes I am aware of that. It makes it easier to draw. But final design in real life is more important than 'easier to draw'. Besides; it is interesting to know how to create this 'challenge'. And I can learn something from it :geek:
Koemi
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Re: 2.5D tube lasercutting ; how to draw?

Postby Koemi » Fri Nov 16, 2018 7:25 am

I also discovered that Partdesign Next (FC V0.17) is quite an improval to Part Design. Cutting cone shapes out of a hollow tube works without errors in the outcome. I definately have to get familiar with this. However, I find it difficult to make the switch to PDNext using older drawings...

Still, PDNext lacks the possibility to project 2D drawings on a bended or round shape (I think...). And so it is still not an easy workaround..
Koemi
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Re: 2.5D tube lasercutting ; how to draw?

Postby Koemi » Fri Nov 16, 2018 10:00 am

chrisb wrote:
Thu Nov 15, 2018 11:55 pm
Perhaps you can find a solution based on the following thoughts:
- Search the forum on how to map a sketch to a cylinder
- Map the sketch to the inside of your tube
- map it enlarged on the outside
- make a subtractive loft.

Something like this. I did not map the faces, it's only to show the loft:
I already tried. Best would be if a loft can be made from a line or point, but that is not possible. I'll try by using FC0.17 instead of FC0.16... ;)
Koemi
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Re: 2.5D tube lasercutting ; how to draw?

Postby Koemi » Fri Nov 16, 2018 10:11 am

I searched the forum using chrisb's tip:
Search the forum on how to map a sketch to a cylinder
And then I found this: https://forum.freecadweb.org/viewtopic. ... 0&start=20

Could be interesting!

If I was able to write code, this is the opportunity to create a tube-laser WB :ugeek:
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meme2704
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Re: 2.5D tube lasercutting ; how to draw?

Postby meme2704 » Fri Nov 16, 2018 11:03 am

I am getting lost in your request (s)
you ask to draw a tube that turns and advances under the fire of a laser beam, this laser is like a milling tool of small diameter which cuts according to a slot of small width always perpendicular to the edges of the slot, so that does not generate not a cone, even when you cut along a curve
In my drawing, I have traced the path of the laser, not the hole that will make the laser
Now you ask to do the sheet "flat" and then rolled, the laser will not make the edges of cut cone but straight (vertical)
then you ask to transform your 2D plans (as on paper) in 3D, there is no magic mouse neither with Fc, nor with other CAD to do that
Koemi
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Re: 2.5D tube lasercutting ; how to draw?

Postby Koemi » Fri Nov 16, 2018 12:25 pm

@meme2704: The sheet flat and rolled was more to describe, not the way I actually want to do this.

Anyway: I think I found the final solution!

By using:
- FCv0.16 (no, not FCv0.17)
- Designing the right sketch :D
- "Wrapping a sketch around a cylinder"-macro
- Cutout of the part created needs to be slightly thicker, otherwise strange stuff happens...

Have nice weekend!

Image
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Grendelbuis_R.FCStd
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meme2704
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Re: 2.5D tube lasercutting ; how to draw?

Postby meme2704 » Fri Nov 16, 2018 12:47 pm

you get that indeed if your laser and very very small
you put at maximun 1 OD int = 6.9mm and ext = 10.8mm bigger, the edges overlap and it makes bizare thing
;)
Koemi
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Re: 2.5D tube lasercutting ; how to draw?

Postby Koemi » Fri Nov 16, 2018 1:37 pm

meme2704 wrote:
Fri Nov 16, 2018 12:47 pm
you get that indeed if your laser and very very small
you put at maximun 1 OD int = 6.9mm and ext = 10.8mm bigger, the edges overlap and it makes bizare thing
;)
Yeah. Try to make these in reality... :shock:
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meme2704
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Re: 2.5D tube lasercutting ; how to draw?

Postby meme2704 » Fri Nov 16, 2018 7:10 pm

A lot of difficulty and disappointment, my idea of using the edge of the cup does not work, there is too much change of direction.
so I draw the cut by hand respecting the directions of the laser according to the axis where it works
I have the result, the piece of waste, and the band burned by the laser
and in V.16 version, but in V.17, or V.18 it is OK too
Attachments
lasercut-2.FCStd
(333 KiB) Downloaded 7 times
lasercut-2.PNG
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