Newbie: Strange behavior

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openBrain
Posts: 1577
Joined: Fri Nov 09, 2018 5:38 pm

Re: Newbie: Strange behavior

Postby openBrain » Wed Feb 13, 2019 10:46 pm

Not too much time to look at it now (time to sleep at WET time zone :) ).
My only quick clue now is that you're talking about "Cut" function. This is a boolean operation and thus will necessarily happen out of the body.
If you want to "remove material" inside a body, you have to use the PartDesign "Pocket" function (or one of the similar ones). ;)
Stonefire
Posts: 33
Joined: Wed Feb 06, 2019 9:49 pm

Re: Newbie: Strange behavior

Postby Stonefire » Thu Feb 14, 2019 9:45 am

Hi

Sorry for my insufficient explanantion. What I ment was that the cut is fine, as I wanted it. But When putting details on the cut/roof they are not depending of the cut structure. fx I can't make extrude that ends on or under the roof - following the loft. I think it must be because that the cut is a part of the body, but not sure....


Sincerly
Steen
openBrain
Posts: 1577
Joined: Fri Nov 09, 2018 5:38 pm

Re: Newbie: Strange behavior

Postby openBrain » Thu Feb 14, 2019 12:08 pm

Sometimes it's getting hard to be clear. Maybe I'm not too. :)
I'll have a look at the file later, but from what I understand at now, your way of doing is not correct.
Actually a cut (which is a BOP) can't be inside a body. This is because the BOPs will perform on the body itself, not with inner elements of it. So cut will necessarily be out of the body and thus breaks links with it. So you can't later easily perform operations that would refer to body faces/edges...
openBrain
Posts: 1577
Joined: Fri Nov 09, 2018 5:38 pm

Re: Newbie: Strange behavior

Postby openBrain » Thu Feb 14, 2019 2:03 pm

OK. I think I better understand what you are trying to do and what is the problem (I hope).
First if you trace the dependency graph of your last posted file, you'll see there is actually a problem (red arrow) as Cut wrongly refer to an body's internal feature.
I know 2 solutions :
1) The dirty one : create another Draft -> Clone of your AdditiveLoft that you don't scale. Redo the Cut by using the not_scaled_clone cut by the scaled_clone. Then select the Cut in the combo view and click on PartDesign -> Create a new body. This will create a new body with a BaseFeature that you can work on.
2) The clean one : delete your Cut but keep your scaled_clone. Check the body is activated, select your scaled_clone and use the PartDesign -> Boolean operation. Check that "Clone" in in the list of bodies (otherwise add it) and select "cut" operation, then validate. You will obtain a boolean cut operation that will be held inside the body so the PartDesign flow can seamlessly continue. I attach the corresponding file.

Hope that helps.
Attachments
3_OB.FCStd
(135.74 KiB) Downloaded 1 time
chrisb
Posts: 16861
Joined: Tue Mar 17, 2015 9:14 am

Re: Newbie: Strange behavior

Postby chrisb » Thu Feb 14, 2019 3:03 pm

3rd way: Delete Cut and Clone. Recreate both with the complete body instead of the loft feature.
Stonefire
Posts: 33
Joined: Wed Feb 06, 2019 9:49 pm

Re: Newbie: Strange behavior

Postby Stonefire » Thu Feb 14, 2019 4:55 pm

Hi both
...and thanks a lot for your surgestions.

OpenBrain - thanks for your file. I'll try to recreate it (..to learn..) and use it for the future work..

chrisb - I'm not quite sure understanding what you mean..

Sincerly
Steen
openBrain
Posts: 1577
Joined: Fri Nov 09, 2018 5:38 pm

Re: Newbie: Strange behavior

Postby openBrain » Thu Feb 14, 2019 5:25 pm

Stonefire wrote:
Thu Feb 14, 2019 4:55 pm
OpenBrain - thanks for your file. I'll try to recreate it (..to learn..) and use it for the future work..
Welcome. I definitely think it's the correct way to go (if you want to learn) ;)
Stonefire wrote:
Thu Feb 14, 2019 4:55 pm
chrisb - I'm not quite sure understanding what you mean..
Actually I know what chrisb said, but I can't succeed doing so (I also tried that before answering to you last time).
I retried now and either get an error either get an empty clone.
But ATM, it's better believe chrisb than me. :) So I hope too that he can provide a more detailed how-to. ;)
Stonefire
Posts: 33
Joined: Wed Feb 06, 2019 9:49 pm

Re: Newbie: Strange behavior

Postby Stonefire » Thu Feb 14, 2019 5:33 pm

Hi Openbrain

Ok - That's maybe why I can't find out. I've tried both your surgestions without any luck...

SIncerly
Steen
openBrain
Posts: 1577
Joined: Fri Nov 09, 2018 5:38 pm

Re: Newbie: Strange behavior

Postby openBrain » Thu Feb 14, 2019 5:40 pm

Stonefire wrote:
Thu Feb 14, 2019 5:33 pm
Ok - That's maybe why I can't find out. I've tried both your surgestions without any luck...
Not sure luck is playing a role there. :) What exactly do you mean ?
You are not able to reproduce what I told, or, you can reproduce but you're stuck at the next step ?
chrisb
Posts: 16861
Joined: Tue Mar 17, 2015 9:14 am

Re: Newbie: Strange behavior

Postby chrisb » Thu Feb 14, 2019 6:41 pm

openBrain wrote:
Thu Feb 14, 2019 5:25 pm
Stonefire wrote:
Thu Feb 14, 2019 4:55 pm
chrisb - I'm not quite sure understanding what you mean..
Actually I know what chrisb said, but I can't succeed doing so (I also tried that before answering to you last time).
I retried now and either get an error either get an empty clone.
But ATM, it's better believe chrisb than me. :) So I hope too that he can provide a more detailed how-to. ;)
Don't believe in the word of a person if you can have a proof - except if it's Normand who is awfully often right. And I have to say that I almost gave up, it took one and a half hour to find.

The culprit is, that the body has no Tip. I don't know how this could happen, but looking at the names I assume that Stonefire has fiddled so much with this body that I'm finally not surprised.
If I set the tip to the loft it works. Here are the steps:

- Delete Cut and Clone, and I all the other rubbish too: unneded sketches, rest of some origin, (and the Part container, making the model smaller).
- Set Tip
- create Clone of Body
- scale it
- Move it slightly towards -Z to avoid coplanarity issues
- Select Body and the Clone and perform a boolean cut.
The result is the attached file - which has shrunk to 1/4 of the size you uploaded.
Attachments
3_cb.FCStd
(96.27 KiB) Downloaded 4 times