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Tolerance in view style
- Thread starter eex23
- Start date
JohnRBaker
Mechanical
I assume that you're referring to the 'Tolerance' for Drafting views, correct?
That being said, why are you asking whether you need to "increase/decrease" this value? What is it that you're seeing which makes you think that it needs to be changed?
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
That being said, why are you asking whether you need to "increase/decrease" this value? What is it that you're seeing which makes you think that it needs to be changed?
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
- Thread starter
- #3
JohnRBaker
Mechanical
That does seem to be a bit large. What size drawing are we talking about? A0? A1?
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
- Thread starter
- #5
JohnRBaker
Mechanical
It's not quite that relative, but for an A0 size drawing, I would expect the default tolerance to have been closer to 0.100 than what I see in you image.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
JohnRBaker
Mechanical
When a drawing view is created, the curves representing the edges of the model are inherited from the model itself, however Silhouette curves and those which need to be computed so as to have a proper hidden-line model are all done as part of the Drawing view creation and this tolerance is used to control the 'accuracy' (perhaps a better term would be how 'precise' the results are) of these curves as seen in a Drawing view and as it is plotted or rendered.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
JohnRBaker
Mechanical
OK, when the system generates a graphic image, particularly in wireframe, such as for Drawing views, Lines, and often Arcs/Conics, are done with graphic primitives which renders them exactly. However for splines (and sometimes Arcs/Conics) this is usually not the case so they are rendered as a series of available graphic primitives usually 'line segments' since they are the easiest to draw and thus render the fastest. However, there is a trade off as to how small and thus how many 'line segments' do we use to represent a free-form curve; the more segments, the 'smoother' the curve will appear, the less, the faster it will render.
So when we say 'Chordal Height' we are talking about the difference between the theoretical curve and the line segments which are being used to render it, as shown in the exaggerated image attached to this post.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
So when we say 'Chordal Height' we are talking about the difference between the theoretical curve and the line segments which are being used to render it, as shown in the exaggerated image attached to this post.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
I only change the view tolerance when lines are missing or obviously misaligned. Sometimes a smaller value actually makes it worse and you have to move to a larger value to get what you want.
Since the move to NX6, I haven't had much need to change the value. From personal experience, I have not noticed much difference in the time it takes to update the drawing whether a small or large value is used, but then again I don't believe I've ever taken it all the way down to 0.
Since the move to NX6, I haven't had much need to change the value. From personal experience, I have not noticed much difference in the time it takes to update the drawing whether a small or large value is used, but then again I don't believe I've ever taken it all the way down to 0.
OK, I changed the view tolerance from 0 to 0.002.......my upper-level assembly drawings (typically "E" size) are still taking over a half-hour to update (9 views).
What are the units of this variable, and can someone suggest an optimun value for a feller that typically makes "B", "C", "D", and "E" size drawings?
Proud Member of the Reality-Based Community..
What are the units of this variable, and can someone suggest an optimun value for a feller that typically makes "B", "C", "D", and "E" size drawings?
Proud Member of the Reality-Based Community..
JohnRBaker
Mechanical
'Capnhook', what modeling unit scheme are you working in, Metric or Imperial?
If you're working in Metric I would set this to around 0.100 and if Imperial units, 0.005.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
If you're working in Metric I would set this to around 0.100 and if Imperial units, 0.005.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
NX 7.5.1.5
The Customer Defaults > Drafting > View > Units System is either "Metric" or "English", and does not convert when the user changes units.....?
I will try "English" at .005, and report back....thanks.
capn
Proud Member of the Reality-Based Community..
The Customer Defaults > Drafting > View > Units System is either "Metric" or "English", and does not convert when the user changes units.....?
I will try "English" at .005, and report back....thanks.
capn
Proud Member of the Reality-Based Community..
JohnRBaker
Mechanical
I would NOT change the setting in Customer Defaults. If you leave it set at 0.0 (which BTW is the out-of-the-box default), NX will automatically calculate what the system feels is an appropriate tolerance based on several factors including, Drawing Units, View Scale, Drawing Scale, Model size, etc. When I gave my recommendations above it was with respect to editing the Chord Height Tolerance on an existing drawing, NOT what you should set in Customer Defaults.
Note that if you open the Help files and search on Chord Height Tolerance and select the first result (General options) you will go to a page which explains all of this and provides examples using images similar to what I posted earlier.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
Note that if you open the Help files and search on Chord Height Tolerance and select the first result (General options) you will go to a page which explains all of this and provides examples using images similar to what I posted earlier.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
OK, help says that an "optimum" value is calculated, based on a few different variables.
So, does this "optimum" refer to optimum drawing accuracy, or optimum time to generate the drawing? Two different requirements here ---- do I have a choice?
Proud Member of the Reality-Based Community..
So, does this "optimum" refer to optimum drawing accuracy, or optimum time to generate the drawing? Two different requirements here ---- do I have a choice?
Proud Member of the Reality-Based Community..
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