20100124

How to make a smooth helix


[Edit: While this is an effective method described here, I also have a new an improved version posted here]
Another repeat question: "How do I make a smooth parametric helix in Revit?"

Here's a quick (2 minute) video. The basic principle is to make a rig with a controlled vertical offset and rotation, and then hang your geometry on it. In this example I use a rectangular form to create the rig, but you could use just about anything.

Suggested listening: Pour Una Cabeza
[Edit: While this is an effective method described here, I also have a new an improved version posted here]


16 comments:

  1. Cool stuff, however I think I like YouTube better, the embedded Vimeo clip did not play.

    ReplyDelete
  2. Hmm, what browser are you using, Robert?

    ReplyDelete
  3. I have used AutoCAD since 1989, but found this video totally incomprehensible. Too small picture, too fast action, I hear no explanation, I do not see exactly in what program it is done (which variant of Revit?) And this is a problem that I have been contemplating...

    ReplyDelete
  4. Thanks for the feedback!

    @Ingolf: The video was shot in Revit Architecture in a Mass.rfa file, but the same functionality is available in all flavors of Revit. And yes, the video is fast and dirty, sorry about that. I’d like to put more production value into these things but I’d rather just get the information out there when I have a chance rather than do nothing. Until then, I have refunded your time. Please expect to live an additional 2 minutes and 29 seconds more than you were previously allotted. BTW, does it help if you use the little “expand to full screen” thingy and the pause button?

    @Stetan: Thx for the thx, but please try and understand that people are jerks when they are anonymous and remote. That’s the price we pay for global communication and I for one am happy to pay it. In fact, I think you owe Ingolf an apology; respect is not something we can demand of anyone.

    ReplyDelete
  5. I followed this to the tee and it keeps telling me i cannot create form :/

    ReplyDelete
  6. @Anonymous: You can't make the form of the piece of spaghetti on the side of the twisted element at the very end? If that is the case, are you sure you hosted the point on the edge? Slide the point around on the edge to make sure. It's really east to accidentally host on the face, and that won't work for making the spaghetti.

    ReplyDelete
  7. Hi Zach,

    this is what I got after following your tutorial:

    image 2
    image 2

    More of a badly bent wire than a true helix (which should be circular when viewed from the top).

    But a nice idea anyway.

    ReplyDelete
  8. Oliver,
    Yes, absolutely, at this scale it is a bent wire. For increased "resolution" you need more points. I find that 60 degree incremental rotations make for very good effect, and 30 degree are even better. It just makes for a tedious video. There is a longer tutorial I'd like to do involving the use of a nested family with a rotation parameter. Thanks for adding illustrations.

    ReplyDelete
  9. Very good work.. Thanks Zack

    ReplyDelete
  10. hi zach i'm nishok .. i did not got this .. i am using revit architecture 2010 ... upto x ray points i got it after tat while rotating its rotating in vertical plne only what we can do for that .. i can't understand through ur vedio clips

    ReplyDelete
  11. Hi Zach, Great video. I've done it many times in Revit 2011 with no problems. However, in Revit 2012, the equality toggle produces an error "Equality Constraints are not satisfied" - Same error in Vasari 2.1. Have you seen this?

    ReplyDelete
  12. Hi Zach, this is a great tip - I love the equality constraint on the profiles. I've done this many times in Revit 2011 with no problems. Revit 2012, however, produces an error when applying the EQ consraint: 'Equality Constraints are not satisfied'. Have you seen this? It also happens in Vasari 2.1.

    ReplyDelete
  13. Argg, thanks John, looks like you've identified a good old fashioned regression. Thanks, I'll pass along the information.

    ReplyDelete