Different arc length dimensions in drafting

[eex23]

Hello,

please look at the attached prt file (nx7). In drafting it is possible to get different arc length dimensions. One dimension value (greater value) is for arc of the sketch, and other (lesser value)is for 3d-centerline.
which one is correct?

NX7.0.1.7 mp2
win xp32 sp3

 

[FrankSwinks]

The sketch curve is a true arc. It has the correct true arc length. The tube centreline is a spline which is an approximation (as close as you want) to the arc. Your tube was created with a tolerance of 0.0254. See the attached image of your tube creation dialog.

Frank Swinkels

 

[eex23]

So what? why there is so big difference in dimensioning? i dont even imagine, that tolerance for tube feature could affect dimension so much (it will be ok if the difference is ~0.5mm, but not differ in twice). why then nx adds this arc length dimension at all, if i select spline (not real arc)? even after changing tolerance do not make any changes in drafting dimensions (i changed tolerance from 0.0254 to 0.0001).

 

[JohnRBaker]

The term 'Arc Length' is a general term referring to the length of ANY curve, not just a portion of a Circle/Arc.

However, that being said, what we're seeing here is a bug which has been fixed in NX 7.5. The dimension of the Sketched Arc is correct, but the length of the '3D Curve' is off by a factor of 2, which happens to be the scale of the view. To see what I mean, edit the scale of your view, changing it from 1:2 to 1:1 and recreate the 'Arc length' dimensions and you will see that they are now both the same

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.

 

[eex23]

Thanks John, is it going to be fixed in nx7 in mr's or mp's?

 

[JohnRBaker]

There are NO More MR's for NX 7.0 and this would not qualify for an MP (it's not a critical bug).

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.

 

[eex23]

And for example, mess with welding symbols in drafting - it is critical bug, or not?

 

[JohnRBaker]

If you have specific examples of problems with Welding Symbols (or anything else for that matter) which you can consistently reproduce, please contact GTAC and have them open an IR/PR so that it can be fixed. Note that we work to resolve ALL KNOWN BUGS, but very little effort is expended on the unknown variety.

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.

 

[eex23]

Contact GTAC means call them or it is possible to email them? what is the procedure to do this?

 

[JohnRBaker]

If you're located here in the US, calling is probably your best bet. If you're not in the US, depending on where you're located, we also have local GTAC organizations which might be your first choice. However, all users have access to many of the GTAC services right from within NX itself. Just go to the 'Help' pull-down menu and look at the options available to you under 'Online Technical Support' item, including options which will allow you to initiate an IR (Incident Report) via the net.

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.

 

[eex23]

ok, thanks.
actualy we are located in europe, lithuania....