Making 90 elbow


#1

I need to draw a 90 degree elbow with 7 gores (segments). I figured i would just make a 90 degree arc, then divide it into 7 points and go from there. Only problem is i don’t know how to divide the arc into 7 points. I also used the shift key to get my 90 degree arc but how can i make a 60 or 45?


(John Brock) #2

Draw the Arc.
Use the Divide command to place 8 points dividing the Arc into 7 equal length segments.
Split the Arc at those points or do what ever you need from there.


#3

Thanks. I drew a pretty 90 degree elbow. I need to unroll it to use as a flat pattern for steel, but when i unroll each gore, the ends that will eventually loop around and touch each other aren’t square. Is there a way i can decide where it makes the cut to unroll


#4

I used the loft command to connect vertical circles along my 90 degree arc. Looking at it now, the 4 lines that run through my circles to make gores are twisted slightly. I bet this is why the ends of my flat pattern isn’t square. I figured you’d need more details to answer


(Pascal Golay) #5

Hi Fabrisol - see if the attached file helps. Loft between two circles that are 1/7 of 90 degrees apart, rotated on the center of the arc. Then UnrollSrf. All segments should be the same, if I understand what you are doing.

ArcSegment.3dm (43.9 KB)

Oops, sorry, it looks like I used 8 segments and not seven, but you’ll get the idea.

-Pascal


#6

unrolled gore.3dm (37.2 KB)
This is what i keep getting. The one you have looks great but i’m not sure what you did different or how you did it.
Thanks


(Pascal Golay) #7

Hi Fabrisol - when you create the loft, align the seam points to the quads of the circles, either the inner or outer quads (Quad osnap). Then the surface will unroll symmetrically.

-Pascal


#8

That was it. Awesome. Thanks