[Solved] Can someone check this compound angle

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jfc4120
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Joined: Sat Jul 02, 2022 11:16 pm

[Solved] Can someone check this compound angle

Post by jfc4120 »

Code: Select all

OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.20.2.29177 +426 (Git)
Build type: Release
Branch: (HEAD detached from 0.20.2)
Hash: 930dd9a76203a3260b1e6256c70c1c3cad8c5cb8
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.3
Locale: English/United States (en_US)
Installed mods: 
  * Curves 0.6.9
  * Help 1.0.3

I saw this youtube video https://www.youtube.com/watch?v=Ta_c3hMqpgA (safe, checked on virus total).

At around minute 11:23 in the video he attaches a 45 to the already 45.

And says he bends a 45 degree with a rotation of 45.

However I get different results, on mine I wasn't concerned about distance, just angles.

I got a 60 degree angle with a rotation of -54.74.

Can someone verify my results. Even if you rotate a 45 over 45, it doesn't fit. On chart, I just ran center lines with no radius since I only wanted angles.

File also attached.
Attachments
p2b.FCStd
(19.38 KiB) Downloaded 21 times
offset1.png
offset1.png (20.93 KiB) Viewed 1138 times
chart.png
chart.png (16.42 KiB) Viewed 1138 times
Last edited by jfc4120 on Sun May 28, 2023 2:18 am, edited 1 time in total.
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thomas-neemann
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Re: Can someone check this compound angle

Post by thomas-neemann »

jfc4120 wrote: Fri May 26, 2023 6:45 pm ... rotation of -54.74.

...
confirm
Bildschirmfoto_2023-05-26_21-02-29.png
Bildschirmfoto_2023-05-26_21-02-29.png (73.41 KiB) Viewed 1117 times
p2b.FCStd
(19.38 KiB) Downloaded 23 times
Gruß Dipl.-Ing. (FH) Thomas Neemann

https://www.youtube.com/@thomasneemann5 ... ry=freecad
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wandererfan
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Re: Can someone check this compound angle

Post by wandererfan »

jfc4120 wrote: Fri May 26, 2023 6:45 pm
FWIW, 54.74 is the angle between the face normals of Rectangle and Extrude with reference to their cross-product. But I think you need the angle with reference to the tangent of the path.

Code: Select all

# the angle between the face normals
>>> rectF1.ParameterRange
(-152.4, 152.4, -152.4, 152.4)
>>> rectF1Norm = rectF1.normalAt(0, 0)
>>> extrF1Norm = extrF1.normalAt(0,0)
>>> angleRad = rectF1Norm.getAngle(extrF1Norm)
>>> math.degrees(angleRad)
54.7356103172454

jfc4120
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Re: Can someone check this compound angle

Post by jfc4120 »

I redrew one with a 45 over and a 45 up and the angles to achieve this are:

35.26 over and 30 degrees up.

A 45 over and a 45 up is always a 60 degree angle of turn. Cos(45) * cos(45) = .5 then arc cosine .5 = 60 degrees.

But he states a 45 degree angle with a rotation of 45 (45 over, 45 up). That won't work for his conditions.

But any double checks is appreciated.
edwilliams16
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Re: Can someone check this compound angle

Post by edwilliams16 »

He rotates the already 90 degree bent pipe by 45 degrees out of the horizontal plane, then he bends it by 45 degrees. The result is as in my file. I don't know what compound angle you are referring to. Can you annotate it?
Screenshot 2023-05-26 at 5.38.55 PM.png
Screenshot 2023-05-26 at 5.38.55 PM.png (16.76 KiB) Viewed 930 times
EDIT: the angle of bend projected on the XY and XZ planes are both 35.2644 degrees. See Sketch002 and Sketch003.
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Tube_bender.FCStd
(8.63 KiB) Downloaded 20 times
jfc4120
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Re: Can someone check this compound angle

Post by jfc4120 »

His box is over 45 and up 45.

He says he bends 45 degrees with a rotation of 45.

However the box, over 45 and up 45 would require a 60 degree bend. I have bent a lot of tubing over the years, I worked with a large Eaton Leonard machine. Also Conrac and many others for aircraft hydraulic and fuel lines, etc.
Attachments
offset3.png
offset3.png (43.42 KiB) Viewed 835 times
offset2.png
offset2.png (14.46 KiB) Viewed 856 times
edwilliams16
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Re: Can someone check this compound angle

Post by edwilliams16 »

His box was ambiguous. I modeled what he constructed.
jfc4120
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Re: Can someone check this compound angle

Post by jfc4120 »

He says a 45 rotation and a 45 bend would fit his box, which was a 45 over and a 45 up. The tube he made would not fit that box is what I am trying to say.

Edit:

In other words to fit a tube in the Box he built with no gaps, to fit against the walls tightly would take a 60 degree bend rotated -54.74 from the 90.

What he bent would still fit in the box but you would have gaps at places.
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Shalmeneser
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Re: Can someone check this compound angle

Post by Shalmeneser »

jfc4120 wrote: Fri May 26, 2023 6:45 pm I saw this youtube video (safe, checked on virus total).
(safe, checked on virus total) ???
jfc4120
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Re: Can someone check this compound angle

Post by jfc4120 »

@Shalmeneser
(safe, checked on virus total) ???
I do not post a link unless I check it with Virustotal.

Are you not familiar with virustotal?
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