Problems with Pad when constructing girder bridge deck

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Shalmeneser
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Re: Problems with Pad when constructing girder bridge deck

Post by Shalmeneser »

All the file was redone to follow the axis, from the beginning.
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

Shalmeneser wrote: Mon Jan 03, 2022 8:46 pm All the file was redone to follow the axis, from the beginning.
I agree and you did say you built it from scratch. Unfortunately, I lost the build flow which I have carefully crafted to describe what each sketch achieves. This makes it easy to understand where I am and where I am going. Any faults can be cleared quickly. With your Rev 1 I do not have that visibility in what is going on and, if I try to look at sketches, the Multi-Transform fails BTW, to see the sketch, I select it from the tree and double click to see it.
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

I have started a new build Rev 4, This was to tidy up the previous builds. All went well until I added the wall. The sketch is fully constrained but when I attempt to pad it it does not appear in the 3D view. I have confirmed that the correct sketch is called up in the Padding settings. I have also confirmed that the sketch is attached to the correct face. I have tried several times to re-do the sketch but with no success. Can someone please help by advising what I am doing wrong please?
Girder Wall Sketch.PNG
Girder Wall Sketch.PNG (124.29 KiB) Viewed 1008 times
Padding.PNG
Padding.PNG (136.05 KiB) Viewed 1008 times
Deck Rev 4 Reduced width.FCStd
(99.33 KiB) Downloaded 7 times
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bambuko
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Re: Problems with Pad when constructing girder bridge deck

Post by bambuko »

just because it is fully constrained, doesn't mean it makes sense to FreeCAD:
problem.png
problem.png (7.29 KiB) Viewed 982 times
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PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

bambuko wrote: Wed Jan 05, 2022 1:20 pm just because it is fully constrained, doesn't mean it makes sense to FreeCAD:

problem.png
Thanks for your reply
I do not understand what has gone on. The first entry in the sketch was the dot on the top wall end of the deck. The second point (the normal line was connected to it and dimensioned. All other dimensions of 2mm were derived from this. I used this to lock the sketch to the body. I have to go out to the shops now but will try again from scratch on this sketch when I get back.
BTW I found hat the second dot on the same face of the wall end caused the inside wall line to seem to be connected directly to it. Sorry but I have to go now.
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Shalmeneser
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Re: Problems with Pad when constructing girder bridge deck

Post by Shalmeneser »

External ligne in Sketch003 should not be upon Pad002 but upon Sketch(000).
Less chance of TNP.
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

Shalmeneser wrote: Wed Jan 05, 2022 8:53 pm External ligne in Sketch003 should not be upon Pad002 but upon Sketch(000).
Less chance of TNP.
Thanks for your reply. Sorry for the delay in my response. My daughter who is self isolating with her two young children called this afternoon,, her boiler had failed and I had to get a couple of oil heaters for her to get the house warm. Just arrived back.
I shall now look into your suggestion and report back.
Kind Regards
Peter.
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

Shalmeneser wrote: Wed Jan 05, 2022 8:53 pm External ligne in Sketch003 should not be upon Pad002 but upon Sketch(000).
Less chance of TNP.
Now, that is very interesting. Looking at Sketch 000 (Pad - Bridge Deck). I had set up the top surface length to be in two lines to anchor the wall structure. When getting to the stage to putting on the wall to the deck, I wondered why I could only find one anchor point and not 2. I chose to ignore this and set sketch 003 to anchor on the only visible portion of the wall end of the top surfDeck.
Before doing anything else, I sorted out Sketch 0003 to be fully constrained and connected to the body at two points, the beginning of the deck and the end of the top surface of the deck.
Sketch 003 Fully contrained & connected.PNG
Sketch 003 Fully contrained & connected.PNG (13.8 KiB) Viewed 844 times
Padding this resulted in this.
Padding following restructure of sketch 003.PNG
Padding following restructure of sketch 003.PNG (128.6 KiB) Viewed 844 times
This did not change if I change the support to Sketch000 or the Bridge Deck Pad nor, if I removed the line to the origin point of the top surface.
With hindsight, perhaps it was not a good idea to use 2 lines to represent the Deck top surface. The tapered Chamfer on the girder end of the top surface is co-incident with the inside inside of the wall and I wonder if this effect resulted from sketch 000.
I shall re-build Sketch 000 to become a single rectangle and try again.
Kind Regards
Peter
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Re: Problems with Pad when constructing girder bridge deck

Post by chrisb »

The Sketch should basically look like this, no T-joints, no double lines:
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PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

chrisb wrote: Thu Jan 06, 2022 5:19 am The Sketch should basically look like this, no T-joints, no double lines:
Thanks for your reply Chris.
The file I posted followed a frantic effort to make a connection hence it is likely to contain multiple lines :oops:
I have carried out rebuilding Sketch000 (Bridge Deck) to be a simple rectangle. Then padded it.
Sketch 000 modified with a simple rectangle.PNG
Sketch 000 modified with a simple rectangle.PNG (77.77 KiB) Viewed 763 times
The next two padding and Linear Pattern had not broken due to the change in Sketch000. This was confirmed by viewing each of these steps.
I then rebuilt Sketch003, Padded it and ended up with the tapering chamfer as before.
I then removed the line, linking the body to the Sketch and lifted the sketch above the Body to show the sketch settings.
Sketch 003 lifted above body with all existing elements showing and link line removed.PNG
Sketch 003 lifted above body with all existing elements showing and link line removed.PNG (133.58 KiB) Viewed 763 times
Note the 1 degree of freedom is the in the Z direction caused by me removing the body connection and moving the sketch up.
Out of interest, and trying to narrow down the issue, I padded again and this is what I saw
Padding following restructure of sketch 000 & Sketch 003 detached from body.PNG
Padding following restructure of sketch 000 & Sketch 003 detached from body.PNG (94.78 KiB) Viewed 763 times
Any comments would be welcome
BTW The Chamfer start position is co-incident with the the RH vertical wall face in the sketch hence my tackling sketch 000 in the first place.
Kind Regards
Peter
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