Looking for suggestions on how to model part

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 From:  twofoot
8336.1 
Hi folks. Please see the pedestal seen in this snapshot circled in red. As you can see, there are a number of complex curves that must combine to form a smooth shape. At this point, I am scratching my head on how to model it.

I've attached the file so you can have a play if you wish.

Thanks!

Chris





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 From:  Frenchy Pilou (PILOU)
8336.2 In reply to 8336.1 
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 From:  OSTexo
8336.3 
Hello twofoot,

It doesn't look like the JPG reference image was embedded.
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 From:  bemfarmer
8336.4 In reply to 8336.1 
Hi twofoot,

To trace an image, a high resolution png file can be used, with MoI display resolution adjusted upwards to MaxTextureSize=8192,
if your video card will support it, as described in an old post. http://moi3d.com/forum/index.php?webtag=MOI&msg=6417.8
Or the blurry png curves can be used.

Several points can be located on one of the curves, somewhere in the middle of the blur, say 6 points.
A combination of Blend and the Clothoid2ptSliders script can be used to fit curves between points.
A clothoid curve can be fitted between two points. Due to the lack of end tangent information for the clothoid script,
it is better to connect separate clothoids with Blend, to maintain smoothness, or tangency.
Maybe MoI4 will have tangent information of a curve accessible to scripts?


Blend can be used by itself, by placing temporary tangent lines at two points, then Blending them, with Bulge adjustment.
After exiting Blend, due to History, the curve remembers that it is based upon the two tangent lines.
So by rotating a tangent line, the curve also adjusts its fit.
The new curve can be extended by using a third temporary tangent line at a third point, with another Blend to the existing curve.

Rebuild should be used, to get rid of a lot of the clothoid points.

- Brian

EDITED: 3 Mar by BEMFARMER


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 From:  twofoot
8336.5 In reply to 8336.4 
I just learned something! LOL

Thank you.
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 From:  twofoot
8336.6 
File with image embedded for those still playing along.

C.

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 From:  twofoot
8336.7 In reply to 8336.6 
Had some success coming back to it tonight with a fresh set of eyes.

Chris
Image Attachments:
Size: 509.1 KB, Downloaded: 38 times, Dimensions: 900x675px
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 From:  bemfarmer
8336.8 In reply to 8336.7 
Looking good twofoot!

The joints at the second horizontal line from the bottom see slightly non-tangent, and perhaps could have a small segment trimmed out,
and be re-blended? Or maybe it is an optical illusion.

Just in general, I've noticed some old blueprints seem to have small non-symmetries, and small inaccuracies.

Did you use shell?

- Brian
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 From:  twofoot
8336.9 In reply to 8336.8 
Hey Brian. There are a number of different extrusions that will occur before it become a fully modeled, 3D piece. That might account for the inaccuracies you mention.

Yes, there are tiny differences to be found in old blueprints. After all, they were done by hand! We take for granted .000001" accuracy, and use it even when it isn't really needed.

One thing I have learned working with these old documents, "back in the day", they were a lot less about aerospace tolerances and more about proper function and longevity. Most times a 1/32" was "good enough".

Chris

EDITED: 4 Mar by TWOFOOT

Image Attachments:
Size: 735.7 KB, Downloaded: 31 times, Dimensions: 1340x1016px
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 From:  BurrMan
8336.10 In reply to 8336.9 
I doodled on it...

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 From:  OSTexo
8336.11 
Hello,

Similar to Burrmans technique, you might also find it helpful to create horizontal and vertical lines, Blend between those lines, and then nudge the lines so the blended curves fall into place.
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