Isn't pivoting a pad casual?

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Batucada
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Isn't pivoting a pad casual?

Post by Batucada »

A pad, set up by means of a sketch on the XZ_Plane, is now to be rotated about 20° around the axis that passes vertically through the centre of the circles in the sketch. The effect should be that the rear end of the tube is turned inwards. I have now tried several variations.
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Bildschirmfoto 2022-08-18 um 09.21.29.png
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chrisb
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Re: Isn't pivoting a pad casual?

Post by chrisb »

It's not clear to me what you want. If you use an AttachmentOffset with a combination of translation and rotation the rotationtranslation is done first. To reverse this you need an additional DatumPlane.
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papyblaise
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Re: Isn't pivoting a pad casual?

Post by papyblaise »

like that :?:
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Shalmeneser
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Re: Isn't pivoting a pad casual?

Post by Shalmeneser »

chrisb wrote: Thu Aug 18, 2022 8:32 am It's not clear to me what you want. If you use an AttachmentOffset with a combination of translation and rotation the rotation is done first. To reverse this you need an additional DatumPlane.
If you use an AttachmentOffset with a combination of translation and rotation the translation is done first.
To reverse this you need an additional DatumPlane.

You can modify the sketch attachment.
The center of the 2nd sketch is attached to the inside vertical line of the 1st sketch.
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Capture d’écran 2022-08-18 105541.jpg
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Last edited by Shalmeneser on Thu Aug 18, 2022 9:05 am, edited 1 time in total.
chrisb
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Re: Isn't pivoting a pad casual?

Post by chrisb »

Shalmeneser wrote: Thu Aug 18, 2022 8:58 am the translation is done first.
Of course, fixed my post.
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papyblaise
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Re: Isn't pivoting a pad casual?

Post by papyblaise »

and if you need 6 off (or more)
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Batucada
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Re: Isn't pivoting a pad casual?

Post by Batucada »

It took me quite a while to get a result. Even when I was working exclusively on the sheet metal bonnet. When, after achieving the first supposed result, I made the base plate (rubber plate) visible again, it was like a punch in the stomach.
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Ergebnis 1.png
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It was not supposed to be like this. I had a reservation with the 1st solution suggestion (Turbine_Blechhaube2) after studying it, because the Z-axis, to which everything should relate, should always be concentric, because then it wouldn't cause any trouble when stacking the other elements. My efforts in the meantime to find an independent solution were not successful. With the next suggestion (Turbine_Blechhaube3) I then also grabbed it, because the author obviously understood what I was aiming at. The picture above disillusioned me. I tried to enter the same value for the X-axis in the body sheet metal bonnet, with which I reached the solution of my problem for the object shaping. Since both values are positive, from a mathematical point of view it makes me doubt whether I have understood the FreeCAD axis model at all. My entered offset works, but I don't know why.
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Ergebnis 2.png
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The joy was short-lived, however, because I realise that I don't understand the axis model at all. In the illustration below, there are a few data (Axis) with which one can manipulate. But what is their meaning? I haven't yet figured out the many possibilities that exist for the world of axes.
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Datenansicht.png
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Who can give me a tip where I can read up on how to proceed specifically? The procedure with Try&Error is just annoying.

The actual number of mouldings is much larger, that would extend the size of the file allowed for the forum considerably.
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Bance
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Re: Isn't pivoting a pad casual?

Post by Bance »

The sketches are attached all over the place, not good...

Check dependency graph for details.
chrisb
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Re: Isn't pivoting a pad casual?

Post by chrisb »

The z-direction is always orthogonal to the attachment plane. If you attach something to XZ plane then local z direction is global x direction, and the other axes act accordingly.
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Batucada
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Re: Isn't pivoting a pad casual?

Post by Batucada »

Hello @Bance

You may well be in a position to judge. Alone, I lack the correct view on things. ""Check dependency graph for details."" Where's the damn beast I'm supposed to be looking for? I'm already trying to study the system and work out the solutions. But in some places I have to pass, I must have slept in the lecture (-‿-).
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