Designation of Helix
Designation of Helix
(OP)
Hello everybody. Happy new year.
I am still stuck in making the helix. Per the attached file shows, I cannot always make a helix I want in a right way. The problem occurs at the direction of it.
I understand the three steps of designating the direction of the helix as:
1. Decide the orientation. (I used the lower side srtaight line by clicking one end of it.)
2. Decide the start point of helix. (I chose the center of the small circle of draft.)
3. Specify the end of helix's centerline, on the basis of STEP 1. (I chose the center of the big circle, which is produced by a intersected curve.)
Then the confusion happened. I don't know why the start/end point of the helix I made is at that position. It seem not belong to any elements. (As my understanding, the start point of helix should be at the center of the small circle.)
Could somebody explain the right steps or understanding of orienting a helix? It will be really appreciated.
I am still stuck in making the helix. Per the attached file shows, I cannot always make a helix I want in a right way. The problem occurs at the direction of it.
I understand the three steps of designating the direction of the helix as:
1. Decide the orientation. (I used the lower side srtaight line by clicking one end of it.)
2. Decide the start point of helix. (I chose the center of the small circle of draft.)
3. Specify the end of helix's centerline, on the basis of STEP 1. (I chose the center of the big circle, which is produced by a intersected curve.)
Then the confusion happened. I don't know why the start/end point of the helix I made is at that position. It seem not belong to any elements. (As my understanding, the start point of helix should be at the center of the small circle.)
Could somebody explain the right steps or understanding of orienting a helix? It will be really appreciated.





RE: Designation of Helix
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/
To an Engineer, the glass is twice as big as it needs to be.
RE: Designation of Helix
Thank you.
RE: Designation of Helix
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/
To an Engineer, the glass is twice as big as it needs to be.
RE: Designation of Helix
But you see, you also said "if no orientation is given", just like what I intended to discribe in my original question.
So, could you please make a little more illustration for me to show how to make a correct orientation for a helix DURING CREATION, besides by adjusting the WCS?
Because I think there must be some methods allowing me to do that, according to the NX 6's 3-step dialog box of helix.
RE: Designation of Helix
It's important to note that if you're thinking that if you were to somehow use an existing snap point and an existing curve to define the origin and direction of a helix, that this would somehow create an associative relationship with the referenced objects, you would be wrong. Irrespective of how you define their origin and orientation, Helix curves are created fixed in space, period! Therefore, if you're looking for some sort of 'associative' helix, you will need to take a different approach, generally involving a Swept Feature using an Angular Law.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/
To an Engineer, the glass is twice as big as it needs to be.
RE: Designation of Helix
Anyway, thank you very much!
RE: Designation of Helix
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/
To an Engineer, the glass is twice as big as it needs to be.
RE: Designation of Helix
I use the helix function every day. I have to use work arounds to get what I require, including using Law Curves. To have a helix that can have variable pitch would make my models so much simpler.
I hope one day this will be incorporated in NX. It has been in Pro/Engineer (spit lol) since I first started usiing it in 1998.
Thanks for your excellent advice as always.
RE: Designation of Helix