need help creating surfaces

[CNC Darren]

Attached is a project I am working on but I am having problems creating the outside surface of the airplane. In the model there are several profile curves along the length of the plane and I had been using the sweep 2 rails function to create the surface between each set of profile curves. I also tried lofting it by selecting the profile curves still didnt work as can be seen in the file. I'm sure there is an easy way to fix this but i am still pretty new to modeling like this.

Thanks for any tips to get this straightend out.

Darren

[DAB_Design]

I think your main problem is that the profile curves are not closed. Meaning they actually have a start and an end point that are not the same. To see this, select one of the curves, and type the command 'crvend' and then 'crvstart'. This will create a point at the end, and start of the curve. Then zoom in real close to see that there is actually a gap/overlap there. Your curve at the edge of the front surface and the back surface is similar, except the ends overlap a little (about .008). That's why the sweep on the front surface 'looks' ok. It actually isn't.

I tried to fix it, but some of the control points overlap the line of symmetry. My best guess is that you mirrored one side to make the other, and then joined them? Looks like your curves overlapped the center line before you mirrored them, thus creating overlapping lines. Where is the curve you used to make the front surface?

There is a simple fix, but will require a little more work to smooth out the curves. You can turn on the EDIT points of the curves and select on the end, and have it 'snap' onto the other end. This would actually make the center point of the curve slightly off center though. I actually did this, and it worked (sort of). It may be best to start over and avoid this to begin with. If you need any help, feel free to email me (dab_design AT sutv DOT com) what ever files you have.

[CNC Darren]

THANKS! Dustin, yes I had mirrored the half profile to make a whole one. things are working much better now. I made the profiles by using a 3 view drawing that had half profiles as a backround and traced them mirrored them and joined them. I just tried another profile and it works much better with your tips!!

Thanks Much

Darren

[DAB_Design]

That's actually the problem I've seen most when people are having problems. Easy thing to watch for, as long as you know to watch for it.