Loft / Shell in Solidworks

First off, I really like this board. Found this place when googling for help with this project i’m currently finishing.

Using Solidworks, I designed a tank that has to fit within a specific area. I was able to complete the lofting on the tank, however ran into minimum curvature error when completing the shelling.

I’ve finished the loft/shell on a previous tank with a similar radius and dimensions (Pic), but getting a problem when using the final dimensions.

If anyone would mind taking a look… I’m sure this is something the more experienced Solidworks users can resolve fairly quickly.

You can probably get it to build by playing around with the wall thickness dimension in the shell feature. If that doesn’t work, you’ll have to go back and loosen up the curves slightly.

Have you tried doing it “manually”, i.e. with two surfaces?

First, loft with existing geometry, but loft as a suface feature, then offset the surface inward by your shell thickness. Then create planar surfaces to close off the ends, trim out, knit, and solidify. This sometimes works where shelling does not.

If the inner surface gives you minimum curvature errors, you can try creating it as an independent surface loft, and tweak the curvature with guide curves.

Man. Thats a really good idea.

I’ll try that tonight, and see what happens.

I was able to resolve the shell issue before by removing an outer rib i had designed in, but the shell wouldn’t allow me to get the necessary thickness needed for the material i planned to use. Hopefully this offset surface idea will help that.

It looks symmetrical. so if you didn’t build it as a half then mirror it, you should try splitting it in half as a solid, and shell it as a half (remember to select the new surface created by splitting it) then mirror it. If you did build it as a half, then roll back, and make it a solid and shell it before you mirrored it. This should work.

also, if those are fillets, try shelling before the fillet, then manually put inner fillets to creat a nominal material thickness

and as a last resort, as stated above, it sometimes works to start out shelling at like 1mm, then go thicker in incriments of .5mm until you are at the desired thickness.

This worked all the time in 2005, used to drive me nuts, because it’s pretty stupid. 2006 seems to shell better, so I rarely have to resort to this anymore.

I second what hitch says. For surfaced/radiused parts the shell almost always fail on me, resorting to so many offset surfaces, lofted and planar surfaces to remove the material…

Your part should shell easily I think. It looks like you have a radius going around the big rectangular end blending into your lofts. If you’re trying to shell the whole thing, my first guess is that this radius is causing your problems. If so, 2 ways to fix it are the previously mentioned radius after shelling, or split the flat rectangular face inside the radius tangent, then shell it.

There are more things to try…


Any luck making your shell work?