[Solved] Need help modelling a rifled barrel

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nobeltnium
Posts: 16
Joined: Fri May 26, 2023 7:24 am

Re: Need help modelling a rifled barrel

Post by nobeltnium »

Oh and i also notice that when using the helix like papyblaise did, my models outer surface have this weird artifact. Can i some how get rid of it?
8ebd9b224eb590ebc9a4.jpg
8ebd9b224eb590ebc9a4.jpg (37.41 KiB) Viewed 609 times
Nobeltnium
drmacro
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Re: Need help modelling a rifled barrel

Post by drmacro »

nobeltnium wrote: Tue May 30, 2023 2:02 pm Wow that's super papyblaise! I really haven't think of that
I was able to reproduce drmarcro method on my model and it works great. But helixing the sketch made things super simple and less work :o

I also notice that with drmacro method, once i introduce the Polar Pattern fundtion it takes a big toll on my machine. Everytime i open/close a sketch or changing the twist rate, FreeCAD will hang for 30-40 seconds even though htop and task manager show little CPU and HDD usage. My rig isn't wimpy either, she has a i5-9400 with 64GB of RAM with FreeCAD using only 2GB. Not sure if this is something every one encounter or there's something wrong on my end.

Nobeltnium.
My method?

I only see my explanation of the coplaner issue and nothing about Polar Pattern...unless you refer to some other thread.

As for the what htop shows, FreeCAD has a lot of single threaded, thus single core, code. So, the number of cores is less a factor than desired. You will find that sometimes you need to try more than one workflow to determine which solution is best.

A helix sweep of a sketch or the Polar pattern of a solid can be very compute intensive. It can depend on various factors which can change with different shapes.
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
drmacro
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Re: Need help modelling a rifled barrel

Post by drmacro »

nobeltnium wrote: Tue May 30, 2023 2:18 pm Oh and i also notice that when using the helix like papyblaise did, my models outer surface have this weird artifact. Can i some how get rid of it?
8ebd9b224eb590ebc9a4.jpg
You can try adjusting these two properties of the solid.
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Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
nobeltnium
Posts: 16
Joined: Fri May 26, 2023 7:24 am

Re: Need help modelling a rifled barrel

Post by nobeltnium »

Hey drmacro.
Sorry i was referring to Shalmeneser. He sent a file with PolarPattern. I mistaken your name for his. Silly me

As for htop i'm seing all of my 6 cores, and none was reach above 40%. I know that helix will take alot of computing power, it just i don't see it showing any where hence the confusion. My fan wasn't even screaming (normally a simple task like open a new firefox tab will rev up the fan like a micro tornado).
You can try adjusting these two properties of the solid.
How do i open the Property View dialog box? I tried right click all the items in the tree view and the tool bar on top but i can't find it.
Also would you mind explain what the Angular and Deviation value in the box do?
Nobeltnium
drmacro
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Re: Need help modelling a rifled barrel

Post by drmacro »

nobeltnium wrote: Tue May 30, 2023 2:37 pm Hey drmacro.
Sorry i was referring to Shalmeneser. He sent a file with PolarPattern. I mistaken your name for his. Silly me

As for htop i'm seing all of my 6 cores, and none was reach above 40%. I know that helix will take alot of computing power, it just i don't see it showing any where hence the confusion. My fan wasn't even screaming (normally a simple task like open a new firefox tab will rev up the fan like a micro tornado).
On my system, Debian, when a intense FC op kicks in I see one of 8 cpu's jump high.
You can try adjusting these two properties of the solid.
How do i open the Property View dialog box? I tried right click all the items in the tree view and the tool bar on top but i can't find it.
Also would you mind explain what the Angular and Deviation value in the box do?
Umm...it's one of the panels in Task view. Unless you've changed things in Preferences. So, select any item in the Tree view and look at the Properties panel.
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
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papyblaise
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Re: Need help modelling a rifled barrel

Post by papyblaise »

outer surface have this weird artifact
If you are talking about this line in helix, it is not an artifact, it is the coulter line of the circle, if you make a simple pad, it is vertical, if you make a helix, it is in helix of course
nobeltnium
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Joined: Fri May 26, 2023 7:24 am

Re: Need help modelling a rifled barrel

Post by nobeltnium »

papyblaise wrote: Tue May 30, 2023 3:12 pm
outer surface have this weird artifact
If you are talking about this line in helix, it is not an artifact, it is the coulter line of the circle, if you make a simple pad, it is vertical, if you make a helix, it is in helix of course
Ah no, if you look closely you will see the outer surface is not smooth. It has low and high spots like sand on the beach. It's like the tube was dented from hammering
Nobeltnium
frcaduser
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Re: Need help modelling a rifled barrel

Post by frcaduser »

nobeltnium wrote: Tue May 30, 2023 4:46 pm Ah no, if you look closely you will see the outer surface is not smooth. It has low and high spots like sand on the beach. It's like the tube was dented from hammering
It might just be an anomaly in FC. Convert it to an .stl file and view it as such. See if it carries over to confirm.
View the file with 3D paint application that comes with the pc or some other equivalent.

frcaduser
nobeltnium
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Re: Need help modelling a rifled barrel

Post by nobeltnium »

I exported the STL like frcaduser suggested and can confirm that the anomaly is carried over.
just_a_mesh.stl
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Changing the properties value like drmacro suggest seems to work, it smooth out the inner and outer surface (Deviation value set to 0.2 still a little jaggy, 0.1 is very good). Not sure if it gonna impact performance for heavy multiple parts documents. But for now that seems to work just fine.
Nobeltnium
frcaduser
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Re: [Solved] Need help modelling a rifled barrel

Post by frcaduser »

Ok, that makes sense. I am currently attempting to use the POV Ray workbench for rendering, and it states there that for good rendering results, a value of between 0.1 - 0.01 is preferred. However, not sure exactly why the helix application is affecting the outer surface texture (whether real or perceived).

frcaduser
Last edited by frcaduser on Tue May 30, 2023 9:08 pm, edited 1 time in total.
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