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Loft problems

Loft problems

Loft problems

(OP)
Anyone know why all of a sudden "edges" are now appearing on my loft?  They are indicated by the "no" symbol in the image.  They are where I have my guide curves (the 2 you can see and the symmetric ones on far sides).  They have not been showing up and now all of a sudden they do and they essentially bisect the surfaces/faces they are causing problems.

Thanks

RE: Loft problems

Is the merge tangent faces box checked?  Hope this helps.

Rob Stupplebeen

RE: Loft problems

(OP)
Some important info, they appear when I uncheck "Merge Tangent Faces".  I know, I know, uncheck it then.  But the reason I unchecked itwas that the first "all of a sudden" was that one of the 4 corners was getting a small radius in it which was cause problems with my filleting.

RE: Loft problems

(OP)
Thanks Rob, I was actually sending my clarification post as you responded.  So basically I misstated my main problem but thought maybe the one I show might be easier to fix. As it turns out it is, but with the undesired result of putting me back in the situation of having the tiny radius in 1 of the loft-created corners.
 

RE: Loft problems

(OP)
This is what I get when I "check" merge, notice that the profile is getting pulled away from the sharp corner that it is.  This just started happening.  I have played with the "Guide Curve Influence" setting but the "To Next Guide Curve" is what is used in these images and seem to produce best results, other do weird things too as the "uncheck" of merge does.

RE: Loft problems

This is a long shot but do you want the faces to be flat (planar)?  If so I would construct 4 planer surfaces.  

Assuming that easy fix does not work are you using a surface or a solid loft?  Could you do a screen capture of the loft while you are editing so we can see the options and the selected curves?  Please label them if it does not come across clearly.  

I would use guide curves at all the corners not the middle of the surfaces but I do not think that your method is wrong just not my way.

I hope this helps.

Rob Stupplebeen

RE: Loft problems

(OP)
Thanks again Rob.  I attached a jpg including image of all sides and iso.  As you can see, the ends are slightly arc'd, the sides are straight @ angle and the length is arc'd so there really arent any planes (per your question).  It is a solid loft.  The image also shows the 2 profile sketches and the 4 guide curve sketches. The 4 guide curves are in the centers of the respective surfaces.  Your corner guide curve idea maybe would be better but I really dont know, I am very beginner at best with lofts and dont have a good feel for the influence the guide curves will have on the loft (just kind of shooting from the hip).

But here is what worked (or got it back working like it was).  I remade the bottom (larger) profile, and the little corner radius/blend went away, allowing me to keep the merge surfaces checked and eliminating all the other stuff that unchecking was doing.

If you have any suggestions I'd love them.  I dont really know anything about surface lofts.

Thanks again for all your help on this.  Right now Im knocking on every piece of wood I come across hoping that that problem doestn arise again.

RE: Loft problems

while in the loft, right click, go to show all connectors. Without using guide curves, SW will automatically place connectors to loft the profiles. sometimes the connectors are not where you want them to be. you can easily adjust them and they snap to verticies.

this may be your problem.

rfus

RE: Loft problems

(OP)
I need the curved profile on the ends, my image doesnt show it, but it's there.  And when I added the guide curves for that, it also appeared to bow the sides, so I added guide curves for the sides to keep them straight.  The bow radius is quite large, and I assume there is some effect that clashes ultimately at the midpoints or more so at the "midpoint" per the "weighted" guide curve changes between each of the guide curves where the closer one takes over as the "midpoint" is moved from (kinda like when moon's gravity took over and started pulling Apollos in 90% of the way there).  But those small changes are fine, this is a thermoformed plastic, panel.  Any insight is greatly appreciated though cause like I said, I am very new to lofts.

RE: Loft problems

I think that you should be able to get this to work for you.  But if you do have more issues I always find surface modeling more controllable than solid modeling.  If you sent your model or more likely a model with only this feature we would be able to help more.  

Are all your guide curves straight?  If so you can probably do a surface sweep with one of your loft sketches as a path and one as a guide curve.

Hope this helps.

Rob Stupplebeen

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