Stuborn Extrude

[hansgeerdink]

Hi,
As I would like to create an extruded surface that wraps around an axle, like a metal pin from a belt or band buckle. However, somehow I cannot get a perfect result using either a extrude- or bi-rail-surface. See attached pics for more detail. Have I missed something? Why is the surface always deforming? (like it is made of some flexible material...)

[design22]

Hmmm, I remember this came up once before. I think one solution, when you create the curve that you will extrude along, is to add some extra CV's at the corners (where it is deforming). Possibly, you might try adding isoparms at these corners (insert) once the surface is created. It might also work if you just increase the isoparms in the control panel.

[design22]

Did this quickly but I think the areas that you mentioned look better

[tekbot]

looks like you are trying to get that to extrude along a single curve. is this true? how did you build the curve(s)?

I typically dont like to try to get too much shape with a single curve. the results are more predictable when its broken up. if someone asked you to change the radius on the bends its easier with separate curve segments.

you can use a combo of edit point curves, keypoint curves(good for what your showing), curve fillets or circles to get the same result.

I used the birail tool and it looks good. sure its a few more clicks, but the results are good.
the extrude tool always seems to distort the section oddly. PLUS, I only really use a few surfacing tools to build anything and everything... and the extrude is not one of them.

[design22]

Yes, I neglected to say that for my example I used monorail

[hansgeerdink]

Thanks a lot for your replies!

donest:
I had tried different numbers of isoparms, also extreme numbers, but no satisfaction...
Possibly the issue is that I am rotating over 180 degrees with one curve as the rail.

Tekbot:
Yes, as your wire file proves, I should have left all curves separated. Instead I created all, the cure, lines and filleted the 3 lines after which I attached all to one main rail.
I had also tried mono-railed and birail... no avail, most likely because of he same reason, the continuous single curves.

Again thank you or your effort! I will give it an other go with separated surfaces. (somehow it does make sense...)

Cheers! Hans

[tekbot]

excellent.
I always avoid multiknot conditions created from attaching surfs and curves. ... not sure why that tool is really even there.

anyways.
if you ever want to check for those. use the OBJECT EDIT > QUERY EDIT and right click on a curve or surface. you will see non-empty spans listed or red arrows showing you the multiknots.

BTW: Query edit is a favorite. it will bring the tool up that was used to create the construction history on a object. if you have a surface fillet that you want to modify, just left click on it with the query edit and the surface fillet options will pop up. cool tool that is under used.

[hansgeerdink]

Cool, I use the querytool quite a bit. (had never noticed/payed attention to the red arrows...)
My main problem is knowing when to create single forms out of multiple curves vs. creating multiple surfaces... This was typically a bad choice, all looks fine now!

Cheers! Hans