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Expression is not working in Seimens NX 11 2

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NiveshSri

Computer
Jul 3, 2016
10
How can I write the following expression in Seimens NX 11 Software?
I want to write following expression ("oal" - "fluteLen" + "diaMajor" * 1.25)
The resulting value should be following 1.98438 inches
where value for Oal=5.5 in, fluteLen=4.0625 in, diaMajor=0.4375 in

Please help me in this regard.









Please See the screenshot of my expressions dialogue box.
 
 https://files.engineering.com/getfile.aspx?folder=5d2a2ba7-6321-42c9-9712-7e91679c2525&file=Image_of_expressions_in_Siemens_NX_11.JPG
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You are starting with a negative value for "oal" in your formula... -5.5 - 4.0625 + 0.4375 * 1.25 = -9.0156
Looks to me like it is working perfectly :)

Ronald van den Broek
Senior Application Engineer
Winterthur Gas & Diesel Ltd
NX9 / TC10.1.2

Building new PLM environment from Scratch using NX12 / TC11
 
yes, NX is correct.
:)
Regards,
Tomas

 
Those wonderful mistakes we overlook ourselves until someone else sees the obvious!

"Wildfires are dangerous, hard to control, and economically catastrophic."

Ben Loosli
 
My previous problem has been solved.
send an image is given below.
2019-05-11_08-27-56_ezmou1.jpg


My next problem is that,I want to write following expression
(helixPitch/2.0)-(("diaCutter"/2)/cos(90-helixAngle))-(helixPitch*0.030)

The resulting value should be following 0.790762 inches
where value for helixPitch=2.38061 in, diaCutter=0.328125 in, helixAngle=30deg

Please help me in this regard.






Please See the screenshot of my expressions dialogue box.
 
You are making the math more complex to read/understand than necessary by using these parentheses :
Helixpitch/2 should not need ()
helixpitch*0.030 should not need ()
why does diaCutter have "" ?
The "" normally marks a string variable and not a number. I would assume you get "data type error" because of this.

another example from your supplied image is this one :
p5 = (oal)-(flutelen)+(diamajor)*1.25
Where the parentheses are completely function-less.

When you use Sinus cosinus functions etc, the way to enter those are by using parentheses
example: sin(45), then the parenthesis are a must but you do not need them to enter the :
p5 = oal-flutelen+diamajor*1.25


Regards,
Tomas

 
Thanks, everyone for the suggestion after putting the formula in following way, the problem solved:---
fluteReliefSetback = (helixPitch/2)-(diacutter/2)/sin(helixAngle)-(helixPitch*0.03)

2019-05-13_23-35-22_uy1jks.jpg


There is another problem too in Helix. I do not know how to put a 3-degree angle in the outward direction. In SolidWorks, there is such an option. I found the end value diameter from there which software calculated automatically. I do not know what calculation software has done to find it. Any help regarding this.
2019-05-13_23-40-36_nsmlkn.jpg

Best Regards
Nivesh.
 
In the current state, the "end value" is simply a constant value that has been entered; it is not the result of a calculation. Note the input boxes for the size start value and the pitch value, both are slightly greyed out and both have the = sign in the right side of the input box. This indicates the value is referencing an expression (which may or may not be the result of an equation). I'm not sure where the 0.5 input came from for the size end value; it may be the last value you entered or it may be the default value that NX uses. If you would like it to reference an expression, click the dropdown (black triangle to the right of the value), choose "formula" and select the desired expression.
 
Mr Cowski you did not understand the issue. I want to know that there is no option to fill a helix angle in the Helical curve tool. So what calculation should I do to get end value diameter? Or there is any way to fill the angle in the tool?
 
I guess that I still don't understand the issue. Can you elaborate on what you mean by "fill a helix angle" and what this has to do with the end value diameter? Perhaps a hand drawn sketch or screenshot from Solidworks showing what you want to achieve would be helpful.
 
Ok. I have mentioned it in one of our Instagram posts. Hope you will understand the issue with the help this.
Untitled_Project_Time_0_00_00_00_-1_q0zzqg.jpg
 
I'm still not quite sure what the "taper helix" is doing. My guess is that the diameter is growing (if "taper outward" option is selected) or shrinking inward over the last N degrees of the helix (the taper angle), but I could be completely wrong here. The solidworks help isn't very clear:

If my guess is correct, then a similar result should be obtainable in NX by using one of the variable diameter options.

www.nxjournaling.com
 
If you are looking for a method for creating a conical helix using the Helix function, you will need to use a law function for the diameter. Attached is a simple conical helix based on a starting diameter, a length, and a cone angle. It creates the curve using the "By Equation" option
 
 https://files.engineering.com/getfile.aspx?folder=e9ca484c-1eb2-46a2-a877-ef561504ea83&file=helix_angle_2.prt
Thanks for the information. But in Nx software, the process seems to be quite tedious. I also use other software, there we can easily fill the angle. Nx should put this in future uploads.
 
I do not see the problem.
Entering an angle or two diameters is really not that big difference,
and the option in NX allows you to do way more complex things in a very simple fashion.

Regards,
Tomas

2019-05-22_10-09-20_irocma.png
 
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