Sweep1 lhs twists and a mess yet mirror of good rhs

[Steve1]

Hi,
V5

1 hr trying to get the lhs sweep1 rail to behave yet its simply a mirror of the rhs.

I have even taken the rhs and mirrored across as its healthy then it still twists !

I have checked dir, and the reference line.

Times like this and its midnight and not eaten yet I wonder what Rhino is up to !

cruel !!!

profiles along lhs were copy of first one lhs. the end profile rhs and lhs were dupEdge of an initial sweep just to the end of the one located at item edge.

SWEEP1 TWISTED.3dm (2.3 MB)

(and yes the profiles are slightly different lhs and rhs, deliberate), hence the ‘meetup’ section either end.

Steve

[Tom_P]

is this (unsymmetric) orientation intended of the cross sections/ profils / shapes ?

explode the rail curve and work through it step by step.
?

this is what i get:

unsure what should happen here:

rh5 file:

SWEEP1 TWISTED_rh5_tp.3dm (2.5 MB)

EDIT:
it would be kind if you mark an Edit as an Edit (as this) if you give more info in the initial post by a edit - great for new readers. but my first question / screenshot now looks like I have not properly read your post. thumbs up for your job to be done. … good night.

[jeremy5 (Jeremy)]

Just pick your cross sections starting from the other end:

When you get something that works and something mirroring it that doesn’t, it is always worth reversing the pick order for the latter.

[Steve1]

Hi Folks,
@Tom_P
Tom, sorry if not clear on what I was after, it (sweep) got twisted and should be as other side though as mentioned the profiles are deliberately non matching, so thought I had said enough and that was ok data wise.

the bit in the middle is obviously going to need to be done separately as I also mentioned, though to avoid confusion I should have taken the ‘double profile’ out from centre of it. I just did that bit by using the straight rail and profile either end of it.

@jeremy5
Jeremy thanks, that worked,…new rule to remember, if it fails try selecting profiles from other end, AND IT WORKS.

Why is that and is this quirk still existing in V8 etc ?

So now with the profile missing brushing against the down finger, I can join and then boolean difference.

OH NOT AGAIN, it fails.
storyboard click twice to enlarge to full.

I do intersect and see oddities, both on good and initial bad sides,

and it intersects with side of down finger, yet profile drawn to miss.

so what to do for the oddities when they dont appear in the result of sweep1.

and if my profile misses why and what to do now ?

SWEEP1 TWISTED now ok but boolean Difference fails.3dm (2.2 MB)

and then I do each bit by bit, I remove the short segment of line and use blendCurve and then join the sweep1 results, I see dark surfaces, so flip them, then boolean difference AND IT WORKS.

5hrs fiddling about on it, one boolean Difference. I dread them.
SWEEP1 TWISTED now ok boolean Difference ok.3dm (2.5 MB)

HOWEVER ITS FAILED AS THERE IS NOW A THING STICKING OUT COMES AND GOES AS I ROTATE.
AND I CANNOT SELECT IT.
OMG.

Steve

[jeremy5 (Jeremy)]

Hi Steve,

First off, looking at your rails, you have tiny sections in between the curves at both ends, like this:

I would delete those and move the end points of the curves that don’t end at the edge up to meet their compatriots. Then you can sweep cleaner faces (but wait…)

Next, your cutter is fouling the side of the upstand:

So junk the idea of a cutter and just sweep the faces of the V you want to be left with (or sweep the pentagons and delete the unnecessary faces):

And then use the V surfaces to trim the solid:

Before joining it all together:

SWEEP1 TWISTED J Solved.3dm (2.0 MB)

HTH
Jeremy

[Steve1]

Hi Jeremy,
those minute bits were the problem, it then worked.
Steve