turn on suggestions

Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.

Showing results for

- Navigation
- Solid Edge
- Forums
- Blogs
- Knowledge Bases

- Siemens PLM Community
- Solid Edge
- Solid Edge Forum
- Dimension in Draft Rounds Down

Options

- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content

07-08-2016 11:54 AM

This is the first time I've noticed this... My driven dimension in a draft rounds down instead of up. Is this the correct behavior? Is there a way to fix it? -Thanks.

Solved! Go to Solution.

6 REPLIES

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content

07-08-2016 12:02 PM

Try this setting:

Bruce Shand

ST10 MP5 - Insight - Win10 - K4200

ST10 MP5 - Insight - Win10 - K4200

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content

07-08-2016 12:04 PM

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content

07-08-2016 01:41 PM

Thanks.

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content

07-08-2016 03:29 PM

There is a difference between what you were taught in grade school and what is required per ASME Y14.5M.

Always rounding the number up proceding a 5 creates a statistical growth bias that can cause enough strung dimensions to push a feature beyond it's intended position.

Increasing the preceding odd number and leaving the proceding even number has the best chance to create an even distribution of growth and shrinkage that should eliminate the statistical bias in either direction.

Example grade school rounding: 1.875 (1.88 grows 5 thousandths) + 1.625 (1.63 grows 5 thousandths) = 3.500 (3.51 using rounded values results in 1 hundredth over target value)

Example ASME rounding: 1.875 (1.88 grows 5 thousandths) + 1.625 (1.62 shrinks 5 thousandths) = 3.500 (3.50 using rounded values results in matching target value)

As you can see this is easily demonstrated with just two values. Imaging having half a dozen in a strung dimension all rounded up and QA/QC guy measuring these by your rounded dimensions. He's a couple hundredths off from the nominal and your part is flagged as out of tolerance!

Ken

Production: ST10 MP5

Testing: SE 2019

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content

07-08-2016 03:46 PM

A good reason not to use chained dimensions too.

Bruce Shand

ST10 MP5 - Insight - Win10 - K4200

ST10 MP5 - Insight - Win10 - K4200

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content

07-08-2016 05:14 PM - edited 07-08-2016 05:37 PM

From the standard SI 10, American National Standard for Use of the International System of Units (SI): The Modern Metric System, in Apendix B.6, Rounding Values...

*When rounding to fewer digits than the total number available, proceed as follows:*

*a) If the first digit discarded is less than 5, do not change the last digit retained. For example, 3.463 25, if rounded to four digits, would be 3.463; if rounded to three digits, 3.46.*

*b) If the first digit discarded is greater than 5, or if it is a 5 followed by at least one digit other than 0, increase the last digit retained by one unit. For example 8.376 52, if rounded to four digits, would be 8.377; if rounded to three digits, 8.38.*

*c) If the first digit discarded is exactly 5, followed only by zeros, round the last digit retained upward if it is an odd number, but make no adjustment if it is an even number. For example, 4.365, when rounded to three digits, becomes 4.36. The number 4.355 would also round to the same value, 4.36, if rounded to three digits.*

Follow Siemens PLM Software

© 2018 Siemens Product Lifecycle Management Software Inc