Shell a Lofted Solid

Have created a Solid by lofting several Profile sketches and using two Rails. Per JD's advice from the Autodesk Student/Educator Community I have cleaned up sketch constraints (I think). Now trying to Shell this Solid but getting "vertex has no solution" error.

Have tried to Loft as surface and thicken but won't work. Have tried to loft as a half model (+Z direction only) and Shell but no go either. Have tried the half model as a surface and thicken errors also. I need a new plan of attack!!!! Here is a screen shot.

Imagine an arc, just a simple 2D arc. Now offset that arc towards the center. As you get closer and closer to the center the offset arc gets smaller and smaller until at some point the radius becomes zero and then negative (undefined).

That is the problem in shelled lofts only much more complex in 3D space with all kinds of curvature. I can see several locations where you might have such a problem but without the file it is impossible to say. Also you need to avoid sharp points (might be one at the origin in your pic) model beyond these points and then cut the model back after shell.

Find the red End of Part marker in your browser.

Drage the EOP above all features hiding the features.

Save the file.

In Windows Explorer right click on the file name and select Send to Compressed (zipped) Folder.

Attach the resulting *.zip file here.

I understand what you're saying. I think that the .zip file I attached is what you are talking about it should be in my original post I don't have the file (at another computer) with me but I will re-post later today.

With the vertex problem how should I draw this part as a .125 shell?.

Whoa!!! When I changed the Point on the nose to a Tangent Condition Shell worked fine. Must be your magic touch JD since i had tried that before with no luck. Thanks

What is the goal with this surface? it almost looks like an aero recumbant bicycle. The surface needs some work i think depending on the end goal. When working with surfaces or lofted solids/surfaces you need to be careful with your rails and with your defining sketches. Your shape as of now seems to have a lot of 'tension' on it. I changed the condition of the point nose to sharp point and it seemed to remove some of this tension. Dont be affraid to work with multiple surfaces and knit them together to create what you want. Trying to drive the entire thing in one loft may produce some unwanted geometry. In the attached image ive pointed to areas. These areas have high/low spots because of how the loft enters/exits your cross sections. Also your top and bottom rail add to this issue. Were the rails created based on the cross sections? Meaning the rails arent really there to drive the loft.

The second drawing ive added shows a few things. The top image shows an overlay of the zebra striped surface created without using the rails. You can see what the surface wants to do. The second is only this new lofted surface. The third is only your current lofted solid(with the nose point changed). The fourth is your lofted solid with the zebra stripe(applied by going to the Inspect tab. The important things to note are the areas where the black stripe is not smooth.

In the last image(front view), the new surface is on the left and your solid is on the right. If the end goal is some sort of aero design you need to play around with these tools you have. The biggest issues that will come up will be lofting through cross sections that have sharp corners. These will typically cause you problems when you go to either thicken a surface or shell a solid. Also poor spline control and using these splines as rails.

Play around with lofted surfaces or Patches. Use as few spline controls as possible to achieve your shape. Be careful not to use too many cross sections and avoid going from sharp corners in cross sections to sketches with none.

You're right, it is a first stab at a velomobile body. I'm much more comfortable with the mechanical parts rather than the body. The rails are there because when I loft it without them I got strange "bumps" in the srface. when I added the rails the body came out symetrical and better shaped. I will continue to experiment and see what I can learn.

do you have any hand sketches or ideas about how you want it to look? When i work with stuff like this I like to work with one side, and i typically dont go all the way to the middle. Ill try to draw something to show you what I mean.

well i got a little time and i drew something real quick.

http://filebox.vt.edu/users/maperez/Cad%20Drawings/aerobike.zip

I drew one half of it, mirrored it then drew the bottom. Keep in mind i didnt fully constrain my sketches. The reason I did it that way was to play with the curves and the shape. Open up 3dsketch1 and more the points around to drive the shape.

Im not saying this is the way you should draw it but i just wanted to show you another way to go about it.