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Vagulus

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I have absolutely no idea whatsoever how to create this model. It's Problem 7.51 from Giesecke F.E., Mitchell A., Spencer H.C., Hill I.L., Dygdon J.T., & Novak J.E. (2014). Technical Drawing. Upper Saddle River (NJ) USA: Prentice Hall, p.238.

 

7-51 Flat Belt  Pulley.jpg

 

Note the spokes have elliptical cross section, and vary in both thickness and width from Hub to Rim. Nothing I have read, watched or heard about equips me for this one. :facepalm:

 

I really would like to know how it is done, if someone has the time to show me.

 

Thanks

Flat Bed Pulley.pdf

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If I were doing the spokes in AutoCAD I might use two ellipses and the Loft command.

 

Same process in Inventor. (or Extrude with taper might work if the taper angle is calculated, but I'm not sure this will return correct major and minor axis. Just use Loft)

 

Somewhat similar (lofted ellipse) post #112 here

http://www.cadtutor.net/forum/showthread.php?85808-Inventor-101/page12

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Thanks to you both, but the more I look at this problem the more complex it gets.

 

 

I thought about Lofting one Spoke and using Circular to draw the other four, but I cannot see how to position the ellipses so that the Spoke blends properly into those thickening spines that support the Hub and Rim.

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Same process in Inventor. (or Extrude with taper might work if the taper angle is calculated, but I'm not sure this will return correct major and minor axis. Just use Loft)

 

Somewhat similar (lofted ellipse) post #112 here

http://www.cadtutor.net/forum/showthread.php?85808-Inventor-101/page12

 

_Flat_Belt_Pulley.jpg

 

As usual the tutorial was the answer. The trick was creating the workplanes in the right place. I was getting confused with using rails.

 

Thanks

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  • 2 weeks later...

Hi JD

 

I'll leave the finer detail for a later day. What you see is about as far as I can get at the moment. However, should you find the time to do it the RIGHT way, and post it so I can see how it is done, I am sure I will learn some useful things.

 

Thanks

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I did :(! It's a problem that the spoke is tapered. I wound up creating two workplanes with the spoke cross-section profiles and then lofting the spoke as a solid.

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Try creating a tangent workplane then sketch and extrude both ways.

 

Try posting your solution to this problem.

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