Absolut vs. Relative model accuracy and the value for company standard

[Mertsy]

Questions related to bidirectional CAD translation in Alias and Pro/E.

1. Config settings:

Alias help recommends the following configuration setting in Pro/E.
Do you see any issues with these setting?

http://download.autodesk.com/us/alias/2011help/index.html

IGES_OUT_ALL_SRFS_AS 128
IGES_OUT_SPL_CRVS_AS_126 YES
IGES_OUT_SPL_SRFS_AS_128 YES
IGES_OUT_MIL_D_28000 NO
IGES_OUT_TRM_SRFS_AS_143 NO
IGES_OUT_TRIM_CURVE_DEVIATION DEFAULT (What does default mean on this one?)
INTF_OUT_BLANKED_ENTITIES NO
INTF3D_OUT_EXTEND_SURFACE YES
INTF3D_OUT_FORCE_SURF_NORMALS YES
IGES_IN_106_F2_AS_SPLINE NO
IGES_IN_DWG_LINE_FONT YES
IGES_IN_DWG_PNT_ENT YES
IGES_IN_DWG_COLOR YES
FIX_BOUNDARIES_ON_IMPORT YES

How do I get to hidden config options? These two appear to be hidden.
Int_in_keep_high_deg_bspl_srfs
Iges_in_dwg_pnt_ent yes

2.Model Accuracy I really need more information on this topic.
Determine best tolerance(s) with which to build in both Alias and Creo
Determine if working in absolute vs. relative in ProE could cause issues
Determine if chosen tolerance value could affect computer performance
Determine if there is a “building” tolerance and an “import” tolerance
Determine how accuracy/tolerances are chosen
Determine the implications of tightening tolerances on “children” only (external copy geometry).
Determine tightest tolerance desired on machined parts
Determine tightest tolerance desired on Class A surface design
Determine if machined parts and Class A surfaces require same tolerance in software
i.Choose tolerance(s) based on above research for software and tooling needs

3.How do I check surface degrees/spans within pro/E

 

[looslib]

Hidden config options are entered in your config.pro using a text editor. There is no menu selection for them or their options while in WF/Creo.

I have attached a PTC document describing accuracy and how it is determined.



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

Ben Loosli

 

[Mertsy]

My questions: See below for explanation of problem.
Should the tolerance of Alias and pro/e be the same?
Should the skeleton parts have the same tolerance as the children parts?
What should the tolerance value be?
Should it be absolute or relative?

I am going to import Alias data into Pro/E (class “A” surfaces)
I am going to use TOP Down Design Skeleton modeling process with in Pro/E. My plan is to use the imported data from Alias as a high level skeleton feature. Then use external copy geom features to translate the imported high level skeleton information down to the children. I will build off of the imported data to build piece parts in body position. Example: head light on the front of a car. Where the imported data from Alisa was the hood fenders bumper and head light surfaces all as one. i will use this surface from Alias as a skeleton feature and copy it to a piece part and build my head light geometry.

Example: .001 Absolute for all Alias file, Por/E: Skeleton with import feature, piece part with external copy geometry from skeleton.